Method of making the shaped products from the copolymere of ethylene and hydrocarbon

The invention relates to articles molded from an ethylene-hydrocarbon copolymer.

There is currently a need for molded plastic articles such as hatches, closures, food and garbage containers, bottles, plates, bowls and toys that are resistant to stress cracking when exposed to detergents, vegetable oils and greases, and / or which would have a higher impact resistance at low temperatures (i.e. g0 ° C).

Attempts have been made to mold these articles from high pressure ethylene homopolymers or mixtures of high density polyethylene and copolymers of ethylene and polar comonomers such as vinyl acetate or ethyl acrylate.

However, articles formed from high pressure polyethylene have insufficient stress cracking resistance and have low 'impact' toughness at low temperatures. Mixtures of polar copolymers with high density polyethylene have better properties in this respect than high pressure polyethylenes, but are very expensive to manufacture, are less transparent, have greater odor, poor electrical properties, high content of hexane extractables and when mixed with. pigments are more prone to color segregation.

It has now been unexpectedly found that articles molded from ethylene-hydrocarbon copolymers have higher stress cracking resistance and better low temperature properties.

Addition . have. The injection molded articles of ethylene and hydrocarbon copolymer have a high surface gloss and do not contain any dull spots (fans). In addition, they have articles formed from these. copolymer excellent bending life, especially when bending across the orientation direction.

In summary, molded articles made by the process of the invention using ethylene-hydrocarbon copolymers as defined below have the following advantages: they have higher stress cracking resistance, better low temperature resistance, high gloss substantially free of frosted fan, little warping and longer bending life.

The ethylene and hydrocarbon copolymers used to make these articles can be prepared in the fluidized bed reactor shown in Figure 1.

The copolymers according to the invention can be copolymers containing ethylene as the main molar proportion (9090%) and minor side as the minor copolymer. (g 10%) one or more C 5 to C 8 alpha-olefin, which should contain no branching on any of its carbon atoms closer to the copolymer backbone than the fourth carbon atom. In the case of the use of one Cs to Ce α-olefin, copolymers are obtained; These α-olefins include propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-heptene, and 1-octene. Preferred α-olefins are propylene, 1-bromo, 1-hexene, 4-methyl-1-pentene and 1-octene.

The copolymers have a melt flow rate ratio of 22 to 32, preferably 25 dd 30, including limit values. The ratio of melt flow rates is another way of characterizing the distribution of the muculocular masses of the polymer. The melt flow rate (MFR) ratio 22 to 32 (including the limiting values) corresponds to a Mw / Mn in the range of about

2.7 to 4.1 and a MEV of from 25 to 30 (including limit values) corresponds to a Mw7 / Mil ratio of about 2.8 to 3.6.

The melt index of the copolymer is an image of molecular weight. The relatively high molecular weight polymers have a relatively low melt flow density. Ultra-high molecular weight ethylene polymers have a high load melt index (HLMI) of about 0.0, and very high weight polymers have a melt flow at high load of up to 0.0 to about 1.0 g / 10 min. Such high molecular weight polymers are difficult to mold in conventional injection molding machines and sometimes are. not at all possible. The polymers produced by the process of the present invention, on the other hand, are easily formed in such a device. They have a melt flow index at normal load (MI) ranging from about 0.0 to about 100, preferably ranging from about 0.5 to 80 and a ihdex melt flow at high load (HLMI) of about 11 to about 2000. The melt index of the polymers produced by the process of the invention is dependent on the combination of the polymerization reaction temperature, the copolymer density, and the hydrogen / monomer ratio in the reaction system.

The melt flow index increases with increasing polymerization temperature and / or decreasing polymer density and / or increasing hydrogen / monomer ratio. In addition to hydrogen, other chain transfer agents such as dialkyl zinc compounds can also be used to further increase the melt flow index of the copolymer.

The copolymers used in the process according to the invention contain g 1 and usually g of 0.1 to 0.3 of C = C double bonds per 1000-carbon atom.

The copolymers used in the process of the present invention have a content of n-hexane extractable ingredients (at 50 ° C) of less than about 3% and preferably less than about 2% by weight.

The copolymers used in the process of the invention contain as catalyst residues of the order of 0 to 20 ppm Ti inclusive at a productivity of 50,000 or more and from 0 to 10 ppm Ti inclusive at a productivity of 100,000 or more and 0-3 ppm inclusive at a productivity of 300,000 or more. . With respect to the remainder C1, Br and I, the content of these elements in the copolymer depends on their content in the precursor.

From the ratio of the amount of titanium to chlorine, bromine or iodine in the original precursor, based on the known value of the product, it can be determined. . based on the titanium residue itself, calculate the content of chlorine, bromine or iodine residues. For many copolymers used according to the invention produced using only chlorine (Gl / Ti with 7) catalyst system components, a chlorine content ranging from 0 dO to 140 ppin, including productivity of 3 ODO or greater, from 0 to 70 ppm inclusive, can be calculated. a productivity of 10,000 or greater and from 0 to 20 ppm at a productivity of 300,000 is not greater. In the process of the invention, the copolymers are readily produced at productivity rates of up to about 1,000,000.

. The copolymers used according to the invention are granular materials having a mean particle size of the order of 0.127 to 1.78 mm and preferably about 0.5 to 1 mm. The particle size is important for the ease of fluidization of the pelymer particles in a bed blow reactor, as discussed below. The co-polymers of the invention have a bulk density of from about 243.3 to about 503 kg / m³.

For forming into objects such as lids, closures, food containers, garbage containers, dishes (bowls, plates), curtains and toys, which must have excellent stress cracking and / or high impact resistance at low temperatures , high gloss or long bending durability, preferably copolymers having a density of 918 to 935 kg / m & lt; 2 & gt;³ including limit values, molecular weight distributions Mw / Mn of 2.7 to 4.1, standard indeix melt of 1 to 100, preferably 7 to 80 g / 10 min, and a cutting module of 206 to 550 MPa.

The copolymers used in the present invention can be prepared by the methods disclosed in U.S. Patent Application Serial No. 892,325 filed March 31, 1978 - (FJ Karol - et al.: Preparation of Ethylene Copolymers in a Fluid Bed Reactor), U.S. Patent Application Ser. No. 89232-2, filed Mar. 31, 1978 (GL Goeke et al.: Impregnated polymerization catalyst, process for its preparation and its use in ethylene copolymerization) and processes which make it possible to obtain ethylene-hydrocarbon copolymers having the aforementioned properties.

The copolymers can easily be prepared by the low pressure fluidized bed process described below, by polymerizing under a specific set of conditions below in the presence of a specific high performance catalyst, also described below.

The compounds used to prepare the highly active catalyst to be used according to the invention include at least one titanium compound, at least one magnesium compound, at least one electron donor compound, at least one activating compound and at least one inert substance as a carrier. The individual components are defined below.

The titanium compound has a structure corresponding to the general formula

Ti (OR) aXb .....

wherein R represents a C 1 to C 14 aliphatic or aromatic hydrocarbon moiety or a radical of formula COR ', wherein R' is a C 1 to C 14 aliphatic or aromatic hydrocarbon radical,

X represents chlorine, bromine, iodine or a mixture thereof,

D denotes the number 0 or 1, b represents the number 2 to 4, inclusive, where the sum of a -j- b is -3 or 4.

Titanium compounds can be used singly in mixtures and include compounds of the formulas TiCl3, TiCl4, Ti (OCH3) Cl3, Ti (OCeH5) C1s, Ti (OCOCH3) C13, and Ti (OC6H6) C13 ·.

The magnesium compound has a structure corresponding to the general formula

MgXa kde

X adds chlorine, bromine, iodine, or mixtures thereof.

These magnesium compounds can be used singly or in combination and include compounds of the formulas MgCl 2, MgBr 3 and MgCl 2, the magnesium compounds being particularly preferred.

In the preparation of the catalysts used in the process according to the invention, 1 mole of the titanium compound is used, and about 0.5 to 56, preferably about 1 to 10 mol, of the magnesium compound.

The titanium compound and the magnesium compound are conveniently used in a form which facilitates their dissolution in the electroidone compound as described below.

The electron-mononuclear compound is an organic compound which is liquid at 25 ° C and in which the titanium compound and the magnesium compound are partially or completely soluble. The electron donor compounds are known either under this name or under the name Lewis base.

The term electron donor compounds refers to such compounds as aliphatic and aromatic carboxylic acid esters, aliphatic ethers, cyclic ethers and aliphatic ketones. Of these -electron donor compounds, C1 -C8 alkyl esters of saturated aliphatic carboxylic acids, C1 -C6 alkyl esters, are preferred. C 2 to C 4 aromatic carboxylic acids, C 2 to C 8 and preferably C 3 to C 4 -aliphatic ethers, C 2 to C 4 cyclic ethers and preferably C 1 to C 4 mono- or di-ethers, C 8 to C 6 and preferably C 8 to C 4 aliphatic ketones.

Most preferred of these electron donor compounds are -methyl formate, ethyl acetate, butylation, ethyl ether, hexyl ether, tetrahydrofuran, dioixane, acetone and methyl isobutyl ketone.

The electron donor compounds may be used singly or in mixtures.

About 1 to 85 moles of titanium are used

213.3! .7!2·:

preferably about 3 to 10 moles of electron donor compound. <i. · - ·>> '. · <:: 17- ·!: ·)? · V_t Activation! - the compound - has a structure corresponding to the general formula - v. ·. ·. ·.>.

<)> 'η ······ .. ·· ····. A - .. RJ / XA t X Γ?. <·'

A1 [R ”]_CXA ·. / ΊΙΌ'ύííi · · bi.v.-u / Ví ?. ' .X-i! ; ··· ^? · Í. · Гл; ,, where. ·

X 'represents, -chlorine or - a group of the general formula · QR' 'and i - - - ·: · ίλ .- ·. = · · · · - - χ each of - · · · ·; "iivR!". - and> .R '”^ ·. •which; they are the same or different, it represents a saturated hydrocarbon radical (Cu). .C r .. = · / · '' · ': ·'. d represents the number · o to · 1,5, - · i. π. > ··; e is 1 or 0, the sum of c-H + id, / - e being, 3; .

The activating compounds may be used singly or in combination and exemplified by the compounds drAl (C3He) and • A1 - (C1H5) 2CH2: h.Al (- C4H8) 3, Ah (C2H5) 3C13, АЩ-СШоШ А1 [СбН1з] з,. , ·.

AHaHtaJs, - · Al (G 2 H 5) 2 H and · Al (C 2 H 5) 2 (OC 2 H 5).

At._: Activation of catalysts used according to. of the invention. using about 10 to 400 and preferably about 10; to. 1Q0 · · moles activation. compound per 1 mole of titanium compound.

Fabricsinpaužívíuié ··. Such as carriers-? they are - particulate solids; ,?.which.' They are inert to the other components of the catalyst composition and to the other active components of the reaction system. The inoculum comprises inorganic scales such as those containing arallium and: a. sulfur and organic substances such as polyolefins, e.g. The carrier uses - in the form of dry - powders, which are. the mean particle size of about 50% by weight is about 15% to about 15% by weight. and at least if it is preferably 0B.rmT / g., the resin should not be absorbed. The drying of the carrier is / is carried out by heating to a temperature of at least 100 ° C. Alternatively, the carrier can be dried at a temperature of at least 200 ° C and then thereafter. can act. ' 1 to 1% by weight of one or more alkyl moieties described above; these modifications include carriers; The alkyl-hihaline compounds provide a catalytic system with increased efficiency and, using such a catalytic system, also have the resulting polyethylene particles having improved morphology.

The catalyst is prepared by first preparing a precursor compound of titanium, a compound, a magnesium and an electron-donor compound as follows, and then contacting the carrier with a carrier: and activating compound in one or more stages? nioh; -bak <is -described ·· next .. The precursor is prepared by dissolving the titanium compound and the magnesium compound in the electro-ondonorous compound. at a temperature of about 20 degrees Celsius to about the boiling point of the electron donor compound. The titanium compound may be: - added to the electron-donor compound before or; after·. the addition of the compound to the dormant at the same time with its addition of the dissolution. the titanium compound and the magnesium compound may be assisted by stirring and, in some cases, the heating of the two compounds, the thermon-donor compound to the boil below. reflux condenser. The value of the titanium and the magnesium compound can be caused by crystallization or by precipitation by means of precipitation of? 5- to? Aliphatic. or aromatic or benzene. . ·: ·,: Ιζ:. ·;. ··.> ..:; · ..

Crystallized ·· · · or! The precipitated precursor can be isolated in the form of fine; «Free moving · particles ·? o · medium. about 10 to 100 and 100% by weight and about 292 to about 535 kg / m @ 2. - (after · Uazing) i '· ··· ·. '· -;' ·. ··.

In the fluidized bed process, particles of 100 microns smaller are preferably used. · The (isolated) particles of the isolated precursors can be regulated by the rate of crystallization or precipitation. :

• · · Like this. ready, preku.rtor. It has a composition corresponding to the general formula. ··. · - ·· ':? <; '·. · Iк · '. · ·: ·? ·. Mg_n; Tit (OR) nXp [ED] .Q · - ·), ·· '· in:' '· · ···; . ·; '' r '. · / ..' ·. r kde. · · · ·. o · ·· -: · ·, · ··. ·:. ·· · · - · - - o · ··. · -. ··

ED · introduces: · electron donor ··^? compound, · · · · - · N ···· :( .Ví ·· ',:! ··' ·.,!>

> .m represents the number from · / 0 - ,, 5-- db · 56; before •• Very · from 1.5 to -S including the limit values,

n. represents · a number. 0 · or 1, · ·.

p. represents a number from 6 to 1 * 6; preferably from about 6 to about 14, and from about 2 to about 85, preferably from about 4 to about 1, including the limit · Values, ·; -..-. ·· - <

Preferably, the aliphatic or aromatic hydrocarbon radical or radical is generally C1 to Cm. · Νζρι ^ <.COR '; wherein R R represents C1 to C14 aliphatic or aromatic hydrocarbon residue and cc.

. X represents a OH (or; bromine or iodine or a mixture thereof);

Index - - at - - .elementary titanium · ..! (Ti) · - means. arabian bang ·· j_Ed_na. - ·> · · - ·. ·. · -T ·.? ·> ·;

. The polymerization activity of the fully activated catalyst is so high that it is. In order to effectively control the reaction rate, it is necessary to dilute precisely. : no ^ ilč ^ m₁• The precursor can be carried out prior to: the precursor being either actively or completely activated, as indicated below, or at the same time as the dilution of the precursor is carried out by mechanical stirring or by mixing of about 0.033 to 1 - and - preferably. about -, ¾¾ - up to 0 -, - 33., - part - _;- of the carrier - with - * weight-carrier: · · · · · · · · · · · · · · · · · · · · ·.

. - -. To be able to be used, it is. need-precursor. - fully - or - partially - activate; That is, they have to be treated by treatment with a sufficient amount of the activating compound to be atoms. contained? v · -prékuг5oru. - converted to active state. It has been found, however, that the method of activating the catalyst is - in order to obtain the active ingredient - in the presence of an inert

213 3 7 2 carriers very important. For example, when attempts have been made to activate the catalyst in a manner similar to that described in U.S. Patent No. 3,989,881, the entire amount of the reducing agent theoretically required to fully activate the catalyst was added to the precursor in suspension in the hydrocarbon, and then the suspension was dried at temperature. from 20 to 80 ° C (including limit values) to remove the solvent and allow the use of a catalyst. In the gas phase operation, a product was obtained which was not sufficiently active in the gas phase fluidized bed operation described below on an industrial scale.

In the preparation of the useful catalyst, activation must be carried out so that at least the last activation stage takes place in the absence of solvent, so that the fully active catalyst is not required to be dried to remove the solvent. Two approaches have been developed to achieve this.

According to a first procedure, the precursor is completely activated outside the reactor in the absence of solvent by mixing the precursor dry with the activating compound. In this dry mixing, the activating compound is preferably used in the soaked state in the carrier. However, this process has the disadvantage that the resulting fully activated catalyst is pyrophoric when it contains above 10% by weight of the activating compound.

According to a second preferred method, the precursor is partially activated outside the polymerization reactor. This partial activation is carried out in a hydrocarbon solvent suspension. The resulting product is then in^ydry^and, and^bRemove the solvent. The partially activated impregnated precursor is fed to a polymerization reactor in which activation by the additional activator is completed.

In the preparation of the catalyst by dry blending, the solid particulate precursor is uniformly mixed with the solid particles of the porous carrier in which the activating compound is absorbed. The activator compound is absorbed into the carrier from its solution in the hydrocarbon solvent such that between 10 and 50% by weight of the activator is stored in 90 to 50% by weight of the carrier.

The amount of precursor, activator and carrier is selected so as to achieve the desired Al / Ti molar ratio and to provide the resulting catalyst with a precursor to carrier weight ratio of less than about 0.50, preferably less than about 0.33. This amount of support provides the necessary dilution of the activated catalyst to allow desired control of the polymerization activity of the catalyst in the reactor. When the final catalyst contains more than 10% by weight of the activator, it is pyrophoric. During dry mixing, which can be carried out at ambient temperature (25 ° C) or below, the dry mixture is · well mixed to avoid heat build-up upon subsequent activation, which is initially exothermic. A catalyst is thus obtained which is fully reduced and activated and can be used as such in a polymerization reactor. It has the nature of free-flowing (loose) substances.

According to the second preferred method, the catalyst is activated in at least two stages. In the first step, the solid particulate precursor diluted with the carrier is partially activated by reacting with an amount of activating compound to obtain a partially activated precursor in which the molar ratio to titanium is about 1 to 10: 1 and preferably about 4 to 8: 1. This partial activation is preferably carried out in a hydrocarbon solvent suspension. The resulting product is then dried to remove the solvent, at a temperature of 20 to 80, preferably 50 to 70 ° C. The resulting product has the character of a free-flowing particulate material and can be readily fed into the polymerization reactor. The partially activated precursor is preferably poorly effective as a polymerization catalyst in the process of the invention. In order to activate the partially activated precursor for ethylene polymerization, an additional activator must be introduced into the polymerization reactor. This completes the activation of the precursor in the reactor. The additional activator compound and the partially activated precursor are preferably fed to the reactor via separate lines. The additional activating compound can be injected into the reactor in the mold. solution in a hydrocarbon solvent such as isopentane, hexane or mineral oil.

This solution typically contains about 2 to 30 percent by weight of the activating compound. The activator can also be added to the reactor in solid form, absorbed in the carrier. The carrier usually contains 10 to 50% by weight of activator. The additional activating compound is added to the reactor in an amount such that an amount of activating compound and titanium compound given in the form of a partially activated precursor of a total Al / Ti molar ratio of about 10 to 400, and preferably about 15 to 60, is achieved in the reactor. the amount of activating compound introduced into the reactor reacts with the partially activated precursor and completes the activation of the titanium compound directly in the reactor.

In a continuous gas phase process such as the fluidized bed process described below, separate batches of partially or fully activated precursor are continuously introduced into the reactor during polymerization, optionally from the simultaneous introduction of separate batches of additional activating compound necessary to complete activation of the partially The activated precursor to replace the active sites of the catalyst that were consumed during the reaction.

The polymerization is carried out by contacting the monomer stream in the gas phase, for example in the fluidized bed process described below, substantially in the absence of catalytic poisons such as moisture, oxygen, carbon monoxide, carbon dioxide and acetylene, in contact with a catalytically effective amount of a fully activated precursor (catalyst) at a pressure and temperature sufficient to initiate polymerization.

In order to achieve the desired density range of the copolymers, it is necessary to copolymerize with ethylene a sufficient amount of carbon chain comonomers of 3 or more carbon atoms to have a C0 to C8 comonomer content of 1 to 10 mole% in the copolymers. to achieve this result depends on the particular comonomers or comonomers used.

The following table lists several different comonomers that must be used for copolymerization with ethylene to produce polymers having a density within the desired range at any given melt flow rate. The table shows, on the one hand, the amount of comonomers needed in the copolymers to achieve these properties, and on the other hand the required comonomer concentration in moles. % in the monomer gas stream that is fed to the reactor.

Komonomer. . mol. mol% % needed in the copolymers needed in the gaseous stream

<td>propylene</td><td>3.0 to 10</td><td>0.2 to 0.9</td>

<td>1-buteri</td><td>2.5 to 7.0</td><td>0.2 to 0.7</td>

<td>1-pentene</td><td>2.0 to 6.0</td><td>0.15 to 0.45</td>

<td>1-hexane</td><td>1.0 to 5.0</td><td>0.12 to 0.4</td>

<td>1-Octene</td><td>0.8 to 4.5</td><td>0.10- to 0.35</td>

. A fluidized bed reaction system that can be used is illustrated in FIG. 1. The reactor 10 consists of a reaction zone 12 and a speed reducing zone 14.

Reaction zone 12 comprises a bed of growing polymer particles, formed polymer particles, and a smaller amount of catalyst fluidized by the continuous flow of polymerizable and modifying gaseous components formed by the make-up gas and the gas recycled to the reaction zone. To maintain the fluidized bed in a fluidized state, the gas mass flow rate through the bed must be greater than the minimum flow rate required for fluidization. Preferably, the lunotimum gas flow through the bed is about

1.5 to about 10X higher, preferably about 3 to 6X higher. minimum gas mass flow rate required for fluidization (Gmf). The Gmf designation for the minimum gas mass flow rate required to achieve fluidization was suggested by CY Wen and YH, Mechanics of Fluidization, Cheniical Engineering Progress Symposium Series, Vol. 62, pp. 100-11 (1966).

It is important that the bed always contain particles that prevent "hot spots" and · trap and distribute the pulverulent catalyst in the reaction zone. Upon commencement of operation, a polymeric particle is usually introduced as a base into the reaction zone before the gas stream is introduced. These particles may be identical to the polymer formed or may be different. When they are different, they withdraw particles of the formed polymer as a front product. Finally, a fluidized bed of particles of the desired polymer displaces the starter bed.

The partially or fully activated precursor (catalyst) used in the fluidized bed is preferably stored in a standby container 32 under an atmosphere of an inert gas such as nitrogen or argon.

Fluidization is achieved by a high rate of gaseous recycle introduced into and through the bed, which is typically of the order of about 50 times higher than the rate of make-up gas. The fluidized bed usually looks like a dense mass of moving particles flowing in the free vortex created by the passage of gas through the bed. . The pressure loss in the bed is equal to or somewhat higher than the weight of the bed divided by the cross-section; the bed is thus dependent on the reactor geometry.

The make-up gas is introduced into the bed at the same rate as the withdrawal rate of the polymer product particles. The make-up gas composition is determined by analyzers 16 located above the bed. The gas analyzer determines the loss of components in the gas to be recycled and accordingly the composition of the make-up gas is adjusted accordingly to keep the composition of the gas mixture in a substantially steady state in the reaction zone.

In order to ensure complete fluidization, the recycle gas and possibly part of the make-up gas is fed into the reactor via a 18-bed inlet. Above the inlet 18 there is a gas distribution plate 20 which assists fluidization of the bed.

The portion of the gaseous stream not reacting in the bed forms recycled gas, which is preferably discharged in the polymerization zone by passing through a zone 14 located above the bed in which the velocity decreases and entrained particles fall back into the bed.

Particle separation may be aided by the inclusion of a cyclone 22, which may either be part of or outside the speed reducing zone 14. If necessary, the recycle gas can then be passed through a filter 24 which is adapted to separate small particles therein in the case of high flow velocities and to prevent dust from depositing on the heat transfer surface. and on the compressor sheets.

The recycle gas is then compressed in a compressor 25 and passed through a heat exchanger 26 where it is stripped of the reaction heat before returning to the bed. By constantly removing the heat of reaction, there is no apparent temperature gradient in the upper part of the bed. The temperature gradient exists in the lower - 152 to. 304 mm bed, between inlet gas temperature and bed rest temperature. It has been observed that the bed almost immediately adapts the temperature of the recycle gas above this bed to the bed zone temperature so that the bed temperature is substantially constant under steady state conditions. The recycle gas is fed to the bottom of the reactor through the inlet 18 'and into the fluidized bed through a distributor plate 20. The compressor 25 may also be placed upstream of the heat exchanger 26 in the direction of flow.

The distributor plate 20 plays an important role in the operation of the reactor. The fluidized bed contains both growing and formed polymer particles and catalyst particles. Since the polymer particles are hot and possibly active, they must be prevented from settling, since if any calm mass is formed, the active catalyst contained in these particles could cause the reaction to continue and the particles would melt due to the heat generated. It is important that the recycle gas is passed through the bed at a rate sufficient to fluidize the particles at the bottom of the bed. The bottom of the bed is formed by a separating plate 20, which plate may be a sieve, a plate with slits, a perforated plate, a plate with caps (analogous to the distillation column trays) and the like.

All portions of the plate may be stationary, or may be of the movable type, such as that described in U.S. Pat. No. 3,297,792. Whatever the plate design, the plate must disperse the recycle gas between the particles at the bottom of the bed and keep them fluidized . The task of the plate is also to support a quiet bed of resin particles when the reactor is not in operation. The movable portions of the plate can be used to extrude polymer particles retained on or within the plate.

As the chain transfer agent, hydrogen can be used. The hydrogen / ethylene molar ratio that can be used is in the range of from about 0 to about 2.0 moles of hydrogen per mole of monomer in the gas stream.

Any gas inert to the catalysts and reactants may also be present in the gas stream. The activator compound is preferably added to the gas recycle system in its hottest part. Preferably, therefore, the activator is introduced into the recycle line downstream of the heat exchanger, such as from the reservoir 27 through line 27A.

As a molecular weight control agent, i.e. how chain transfer agents, in addition to the hydrogen catalyst, compounds of the formula

Zn (R^and) (R^b) where

Ra a- R_b are the same or different C 1 to C 14 aliphatic or -aromatic hydrocarbon residues.

This further increases the melt flow indelx values ​​of the produced copolymers. About 0 to 50, and preferably about 20 to 30 moles of zinc compound (calculated as Zn) per mole of titanium compound (calculated as Ti) can be added to the gaseous stream introduced into the reactor. The zinc compound was. it can be introduced into the reactor preferably in a reactor. in the form of a dilute solution (2 to 30% by weight) in a hydrocarbon solvent or in an absorbed form in a solid diluent such as silica of the type described above, in an amount ranging from about 10 to 50% by weight. These substances are often pyrophoric. The zinc compound may be introduced either alone, or optionally together with an activating compound from a dosing device, not shown in the figure, and which may be placed adjacent to the dosing device 27. It is reported near the hottest part of the gas recycling system.

The fluidized bed reactor must operate at a temperature below the sintering temperature of the polymer particles. In order to prevent sintering of the particles, the working temperature must be below the sintering temperature. The production of ethylene copolymers is preferably carried out at a temperature of about 30 to about 115 ° C, most preferably at a temperature of about 75 to 95 ° C. Temperatures of from about 75 to 95 ° C are used to produce products with a density of about 910 to 920 kg / m 3 and temperatures of about 80 to 100 ° C are used to produce products with a density of 920 to 940 kg / m 3³.

The fluidized bed reactor is operated at a pressure of up to about 6.87 MPa, preferably at a pressure of about 1.03 to 2.40 MPa, and when working at higher pressures within this range, heat transfer is facilitated, pressure results in an increase in the unit-volume heat capacity of the gas.

A partially or fully activated precursor is injected into the bed at a rate equal to the rate at which it is consumed by an inlet 30 located above the manifold plate 20. An important feature of the invention is that the catalyst is injected at a point above the manifold plate. Since the catalysts are highly active, injection into the space below the manifold plate could result in initiation of β-polymerization at this point, which could eventually lead to clogging of the manifold plate. Injection of the catalyst into the fluidized bed, in turn, aids in catalyst distribution in the bed and prevents the formation of sites with high catalyst concentrations that would. . could lead to hot spots.

For introducing a partially or fully reduced precursor and optionally a non-gaseous activating compound or transfer agent into the^: a gas inert to the catalyst, such as nitrogen or argon, is used.

Bed productivity is controlled by catalyst injection rate. Bed productivity can simply be increased by increasing the catalyst injection rate.

Since any change in catalyst injection rate results in a change in reaction heat evolution rate, the recycle gas temperature is adjusted up or down to accommodate the heat evolution rate. This ensures a substantially constant temperature in the bed. Both the fluidized bed and the recycle gas cooling system must, of course, be equipped with appropriate devices to detect temperature changes in the bed with the cooling system so that the operator can appropriately adjust the recycle gas temperature.

Under a certain combination of operating conditions, the fluidized bed is maintained at substantially the same height by withdrawing a portion of the bed as product at the same rate as the rate of particle formation of the polymer product. Since the rate of heat evolution is directly proportional to product formation, measuring the increase in gas temperature along the reactor (i.e. temperature difference (between the temperature of the incoming gas and the temperature of the outgoing gas).

The polymer product particles are preferably taken continuously through line 34 or near the distributor plate 20. The particles are collected in the form of a suspension with a portion of the gaseous stream that is vented before the particles settle to prevent further polymerization and sintering before the particles reach zone where they collect. The suspending gas can also be used to transfer the product from one reactor to the other.

The polymer product particles are expediently and preferably removed by means of two sequentially operated time-adjusted valves 36 and 38 between which a separation zone 40 is provided. When the valve 38 is closed, the valve 36 is opened so that it permits the gas-product mixture to enter the zone 40. The valve 38 is then opened to transfer the product to the outer insulation zone. The valve 38 is then closed and closed until the product is removed.

Finally, the fluidized bed reactor is equipped with a suitable venting system to allow venting of the bed at start-up and shutdown. The reactor does not require the use of any mixing and / or wall scraping devices.

The highly active supported catalyst system of the present invention provides a fluidized bed product having an average particle size of about 0.127 to 1.78 mm, preferably about 0.50 to 1.0 mm.

The feed monomer feed stream, optionally with inert gaseous diluents, is fed to the reactor at a rate such that a space and time yield of about 32.4 to about 162.2 kg / hr / m 2 is achieved.³ bed volume.

The term "crude resin or polymer" as used herein refers to a polymer in granular form as obtained from a polymerization reactor.

Additives such as fillers, pigments, stabilizers, antioxidants, lubricants, flame retardants, UV absorbers, emollients, foaming agents, etc. may be added to the copolymers described in amounts that achieve the desired effect.

The products produced using the copolymers of the invention are shaped by methods known per se, such as, for example, injection molding, rotary casting and blow molding.

Products such as lids, closures, food containers and garbage containers, plates, bowls, and toys are injection molded using well known piston or worm machines. For example, injection of polyethylene is described in Renfrew and Morgan: "Polythene" II. eds., Interscience Publisher (1960) pp. 549-570.

The products produced according to the invention are molded on standard injection molding machines. In doing so, the copolymer is heated to a temperature of about 18.0 to 270 ° C in the sieve until it is in a plastic state and then injected from an overpressure of about 3,435 to about 13,740 MPa into the mold cavity of the desired shape. In the mold cavity, the copolymer is cooled at a temperature of from about 15 to about 60 ° C until the shape of the mold cavity is maintained. The product is then removed from the mold.

Products such as bottles and containers are injection molded or extrusion blow molded. Also these methods are well known. For example, polyethylene sprays are described in Renfrow and Morgan, supra, pp. 571-579. In injection blow molding, the copolymer is first heated to the same temperature in the machine as in the above process, and then the resin is injected into the mold cavity maintained at a temperature near the melting point of the resin, preferably at 80 to 120 degrees Celsius. There, it is formed into a pre-blown blank of cylindrical shape, which is then converted into another cooler form of the desired shape. In this second mold, the blank is delivered to the blank by pressurizing. air, which presses the workpiece against the walls of the mold cavity. The walls of the mold cool the product and then remove it from the mold.

For example, extrusion blow molding is effected by extruding a copolymer tube into a split mold, which is then sealed to close the tube at any one of its ends. The tube is then blown out, for example, with air, whereby the resin is pressed against the inner surface of the mold. The molding is cooled, the mold is opened and the product is removed.

Products such as large toys and food containers - and - waste, industrial sizes, are produced by rotary casting rather than spraying. This method is preferable because the products have a complex shape and are more economical to produce even at low volume. Rotary casting is a well-known technology, as described, for example, in the Encyclopedia of Polmer Science and Technology vol. 9, Interscience Publisher, 1968 on pages 118-137.^:

In this process, either the pulverulent resin, or the fine resin particles, is placed in the cavities of the metal mold, which is then rotated - tempered in the oven to a temperature of 260 to 250 ° C. 316 [deg.] C. until the resin has melted and coated the inner mold surface. The mold containing the molten resin is then transferred to a cooling device, where it is cooled, until the molten resin solidifies and takes the form of a mold cavity.

Prior to processing by the above methods, the copolymer may be mixed with various additives, and then the resulting mixture may be fed into a forming machine or the copolymer and the additives may be directly fed into the forming machine.

Examples of products made by shaping ethylene-hydrocarbon copolymers include lids, closures, food containers, garbage containers, dishes, bottles, toys, curtains, etc.

These products may be further adapted to the requirements of the intended use in any way, for example by coating, varnishing, etc.

The following examples serve to illustrate the method of making the shaped articles of the invention. The examples are illustrative only, but do not limit the scope of the invention in any way.

The properties of the polymers produced in the examples are determined by the following test methods:

Density

ASTM D-15i05: A test plate is made and tempered at 100 ° C for 1 hour to approach equilibrium crystallinity. The density measurement is performed in a density gradient column and density is expressed in kg / m 3.

Melt Flow Index - (MI)

ASTM D-1238-Dmdition E measurements are performed at 190 ° C, v-g data per 10 minutes.

Flow rate (melt flow index at higher load) (HLMI)

ASTM D-1238 Condition F

The measurement is performed using a 10-fold load than when measuring the melt index

The ratio of the flow rate = m to the melt index

Molecular weight distribution (Mw / Mn)

It is determined by gel chromatography on Styrogel with a pore size sequence⁶, юз, 102.6-nm. Perchlorethylene at 117 ° C is used as solvent. Detection is by infrared radiation at 3.45 μια.

Unsaturation

Unsaturation is measured using an infrared spectrophotometer (Perkin Elrner Model 21). The resin is used to make moldings having a thickness of 0.635 mm which serve as test specimens. Absorbance is measured at 10.35 μτα in the case of transvinylidene unsaturation, at 11.0 μτα in the case of terminal vinyl unsaturation and at 11.25 μα in the case of vinylldene unsaturation in the side chains. Absorbance per 1 mm of molding thickness is proportional to the multiple of the concentration of unsaturation - and absorbency. Absorbency values ​​are taken from RJ de Kock, et al., J. Polymeric Science, Part B, -2, -339 '(1964).

Example I

Preparation of precursors

In a 5 liter flask equipped with a mechanical stirrer, 16.0 g (0.168 mol) of anhydrous magnesium chloride under nitrogen are mixed with 850 ml of pure tetrahydrofuran. The mixture was stirred at room temperature (about 25 ° C) and 13.05 g (0.069 mol) of titanium tetrachloride was added dropwise. At the end of the addition, the contents of the flask were refluxed for 1 to 1 hour to dissolve the solids. The system was cooled to room temperature and then 3 liters of pure n-hexane were slowly added over 1 hour. A yellow solid precipitates. The supernatant was decanted and the solid was washed three times with 1 liter of n-hexane. The solids are then filtered off and dried in a rotary evaporator at 40 to -60 ° C. 55 g of a solid precursor are obtained.

At this point, the precursor can be analyzed for the content of magnesium and titanium, since certain amounts of the magnesium and / or titanium compound may have been lost in the isolation of the precursor. The empirical formulas used herein to characterize the precursor composition are derived from the assumption that magnesium and titanium still exist in the form of compounds that were originally added to the electron donor compound and that the remaining weight of the precursor is the electron donor compound.

Analysis of the solid gave a composition of Mg: 6.1%, Ti: 4.9%, which corresponds to the formula

Tmg2.45C18'9 [THF] 7.0 'where

THF is tetrahydrofuran.

Example II

Activation procedures

Procedure

This activation procedure involves a multi-step activation of the precursor. Activation is carried out in the tornito process such that the precursor is only partially activated prior to introduction into the polymerization reactor, and completion of the activation is carried out in the reactor.

The required weight of dry inert carrier is placed in the mixing vessel or drum. In the examples described herein, about 500 g of silica or about 1000 g of polyethylene carrier are used as a carrier. The inert carrier is then mixed with a sufficient amount of an anhydrous aliphatic hydrocarbon diluent, such as isopentane, to form a suspension. Usually about 4 to 7 ml of diluent per g of inert carrier is required. The desired weight of the precursor is then placed in a mixing vessel and thoroughly mixed with the suspension. In the examples given herein, about 80 to 135 grams of precursor containing 1 + 0.1 mmol of titanium per gram of precursor are used to produce the catalysts.

The required amount of activator required to partially activate the precursor is added to the contents of the mixing vessel. The amount of activator used is such that the Al / Ti ratio in the partially reduced precursor is up to 10-: 1 and preferably 4 to 8: 1. The activator is added to the mixing drum in the form of a solution containing about 20% by weight of the activator (in these examples triethyl aluminum) in an inert aliphatic hydrocarbon solvent (in these examples hexane). Activation is accomplished by thoroughly mixing and contacting the activator with the precursor. All the operations described above are carried out at room temperature and at atmospheric pressure under an inert atmosphere.

The resulting suspension is dried with a stream of dry inert gas, such as nitrogen or hydrogen, at ambient pressure and at a temperature of up to 60 ° C to remove the hydrocarbon diluent. This usually requires about 3 to 5 ho20 din. The substance is in the form of a free-flowing pulverulent material consisting of a uniform mixture of activated precursor with an inert carrier. The dried non-pyrophoric product is stored under an inert gas.

When the additional activator according to Treatment A is introduced into the polymerization reactor to complete activation of the precursor, the activator may first be absorbed in an inert carrier such as silica gel or polyethylene, but most preferably introduced into the reactor as a dilute solution in a hydrocarbon solvent such as isopentane.

When the activator is to be absorbed in the silica gel carrier, the two substances are mixed together in a container containing about 4 ml of isopentane per gram of carrier. The resulting suspension is then dried for about 3-5 hours under a stream of nitrogen at atmospheric pressure at 65 and 10 ° C to remove the hydrocarbon diluent.

When the activator is injected into the polymerization system in the form of a dilute solution, a concentration of about 5 to 10% by weight is preferably used.

Regardless of the method of introducing the activator into the polymerization reactor to complete activation of the precursor, the activator is used in an amount such that the Al / Ti ratio in the polymerization reactor is maintained at from 10 to 400: 1 and preferably from 10 to 10: 1. , including limit values.

The silica is dried at at least 200 ° C for at least 4 hours before use.

Procedure В

In this process, complete activation of the precursor is accomplished by contacting the precursor during mixing with the activator absorbed in the inert carrier.

The activator is absorbed in an inert carrier by suspending it together with the carrier in an inert hydrocarbon solvent and then drying the suspension to remove the solvent. The resulting mixture contains about 10 to 50% by weight of the activator. The procedure is as follows: 500 g of silica (previously dried at 800 ° C for 4 hours) are placed in a mixing vessel. The required amount of activator in the form of a 20% by weight solution in a hydrocarbon solvent such as hexane is then added to the mixing vessel, and the mixture is mixed, suspended with an inert carrier at room temperature and atmospheric pressure. Then, the solvent is evaporated by drying the resulting suspension at 65 + 10 for about 3-5 hours at atmospheric pressure with a stream of dry inert gas such as nitrogen. The dried composition is in the form of particulate particles having the same size as the particles of the carrier used.

Approximately 500 g of dried silica on which the activator is applied (in a 50/50 ratio by weight) is introduced into a mixing vessel and the desired weight of precursors (80 to 100 g) is added. The substances are thoroughly mixed for 1 to 3 hours at a temperature

At atmospheric pressure under a dry inert gas such as nitrogen or argon¹.

The resulting mixture is in the form of a physical mixture of bulk particles having a size of the order of 10 to 150 μπι. During mixing, the activator comes on a carrier with a precursor and activates it completely. During the thermothermal reaction, the catalyst temperature should not exceed 50 ° C to prevent any catalyst deactivation. The resulting activated catalyst has an Al / Ti ratio of about 10 to 50 and, if it contains more than 10% by weight of the activator, may be pyrophoric. It is stored under a dry inert gas such as nitrogen or argon before being fed into the reactor.

Example 1

Ethylene is copolymerized with propylene or 1-butene (in Examples 1 to 2 with propylene and in Examples 3 to 13 with 1-butene. In all examples, a catalyst prepared as described above and activated by an activation process is used.

A. Polymers having a density of 940 kg / m 3 or less are produced.

In all cases, the partially activated precursor has an Al / Ti molar ratio of 4.4 to 4.5

5.8. The activation of the precursor in the polymerization reactor is accomplished with triethylaluminum which is used either in the form of a 5% by weight isopentane solution (Examples 1 to 3 and 4 to 13) or in adsorbed form on silica 50/50 (Examples) 4 and 5) in an amount so as to obtain a fully activated catalyst with a molar ratio in the reactor. Al / Ti of about 29 to 140.

Each of the reactions is carried out continuously in a fluidized bed reaction system for 1 hour after reaching equilibrium at a pressure of 2.06 MPa · at a gas velocity of about five to six times Gmf and a space-based yield of 48.7 to 97, 3 kg / m^of/ h.

The reaction system described above is shown. Its lower part is 3.05 m high. and · its inside diameter is 0.343 m. The upper part is high

4.88 .... m and its 'inside diameter' is 0.597 m.

In several examples, diethyl zinc (as a 2.6% by weight solution in isopentane) is added during the reaction to maintain a constant Zn / Ti ratio. When diethylzinc was used, triethyl aluminum was also added in the form of an isopentane solution at a concentration of 2.6% by weight.

The following Table A lists the various operating conditions used in Examples 1 to 13, i.e. the content of the precursor in the mixture of the precursor and silicon dioxide · (% / weight); the Al / Ti ratio in the partially activated precursor, the Al / Ti ratio maintained in the reactor; polymerization temperature; reactor ethylene content (·% v / v); hydrogen / ethylene molar ratio; mole ratio of comonomer _ (Οχ) to ethylene (Ca) in the reactor and catalyst productivity.

Table B lists the properties of the granular raw resins produced in Examples 1 to 13, i.e. density, melt index (MI), melt flow rate (MFR), bulk density and mean particle size.

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The reaction conditions in Examples 1 to 13

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Table B

Properties of the polymers produced in Examples 1 to 13

<td>Example</td><td>Density [kg / m³]</td><td>Melt flow index [g / 10 min]</td><td>Ratio of melt flow rates</td><td>Bulk density [kg / m³]</td><td>Mean particle size [mm]</td>

<td> 1</td><td> 927</td><td> 22,0</td><td> 24,4</td><td> 272,5</td><td> 0,58</td>

<td> 2</td><td> 929</td><td> 24,0</td><td> 23,4</td><td> 283,8</td><td> 0,58</td>

<td> 3</td><td> 925</td><td> 0,61</td><td> 27,1</td><td> 272,5</td><td> 0,76</td>

<td> 4</td><td> 931</td><td> 12,0</td><td> 26,7</td><td> 27,2,5</td><td> 0,70</td>

<td> 5</td><td> 923</td><td> 1,47</td><td> 28,2</td><td> 253,0</td><td> 1,03</td>

<td> 6</td><td> 919</td><td> 3,41</td><td> 25,9</td><td> 27.2,5</td><td> 1,40</td>

<td> 7</td><td> 925</td><td> 2,90</td><td> 24,5</td><td> 283,8</td><td> 1,50</td>

<td> 8</td><td> 919</td><td> 3,10</td><td> 24,6</td><td> 262,8</td><td> 1,45</td>

<td> 9</td><td> 929</td><td> 16,0</td><td> 24,1</td><td> 280,6</td><td> 0,58</td>

<td> 10</td><td> 929</td><td> 15,3</td><td> 24,0</td><td> 269,2</td><td> 0,59</td>

<td> 11</td><td> 928</td><td> 11,5</td><td> 24,1</td><td> 270,9</td><td> 0,63</td>

<td> 12</td><td> 929</td><td> 20,,7</td><td> 24,3</td><td> 280,6</td><td> 0,65</td>

<td> 13</td><td> 929</td><td> 29,2</td><td> 26,1</td><td> 272,5</td><td> 0,52</td>

Example 2 - Control

High pressure commercially available polyethylene resins, [Union Carbide DNDA 0415] produced in a stirred reactor at a pressure of 110 MPa and at a temperature of 205 ° C were used as the control resin.

Example 3

The resins prepared according to Examples 1 and 2 were injected into bowls and lids using an Impco (227 g) and Moslo (85 g) injection molding machine.

The bowls were injected on an Impoo machine (227 g) at a roller temperature of 260 ° C, at an injection pressure of 9.62 MPa. The mold closing time is 44 seconds. Other machine-related data are listed in Table I.

The caps are injected on a Moslo piston machine (85 · g) at a temperature of 285 ° C, a pressure of 5.67 MPa, and a mold closing time of 15 s. The caps have an inlet center, the inlet channel diameter is 0.76 mm, mouth length 0.76 mm, lid diameter 1S2.4 mm, thickness 1- mm. The other conditions are given in Table 1.

Table I

<td>Type of machine</td><td>Impco</td><td>Moslo</td>

<td>Injection pressure [MPa]</td><td> 9,62</td><td> 5,67</td>

<td>Roller temperature [PC]</td><td></td><td></td>

<td>nozzle</td><td> 260</td><td> 260 — 288</td>

<td>front part</td><td> 260</td><td> —</td>

<td>middle part</td><td> 260</td><td> 260 — 288</td>

<td>rear</td><td> 232</td><td> 246 — 274</td>

<td>Mold temperature [° C]</td><td></td><td></td>

<td>movable part</td><td> 26,7</td><td> 11,1</td>

<td>fixed part</td><td> 23,4</td><td> 11,1</td>

<td>Blade length [s]</td><td></td><td></td>

<td>injection molding</td><td> 12</td><td> 2 — 3</td>

<td>mold clamping time</td><td> 44</td><td> 15</td>

<td>booster time</td><td> 4</td><td> 1,5</td>

<td>prepack time</td><td> 4</td><td> 2</td>

<td>injection delay time</td><td> 12</td><td> —</td>

<td>time from injection to injection</td><td> 72</td><td> 18</td>

Each of the resins of Examples 1 and 2 was tested for the cutting modulus of elasticity of ASTM D 638. Table II also lists the melt index, density, and flow rate ratio of these resins.

The lids are tested for resistance to stress cracking in Crisco oil. The lids are bent so that the opposite outer edges are pressed together and joined. clamp. The bent part of the cap opposite the clasped edges is burned into Crisco oil and left in it until cracks develop. The results are shown in Table II.

The low temperature impact toughness of the trays is measured at a temperature of -40 to -51 ° C by lowering the cylindrical hammer of a weight to the area of ​​the tray inflow with gradually increasing heights (height increases by 76.2 mm each).

4.54 kg, 25.4 mm 'round head, until the bowl shatters or punctures.

The height at which the dish is broken is multiplied by the weight of the hammer and the result obtained in kgm is recalculated to J.

The degree of deformation and gloss are determined by visual observation and compared with the results obtained for the same molded under the same conditions of high-pressure polyethylene having the same melt index and density.

The results show that the articles molded from the ethylene-hydrocarbon copolymer of the invention have a higher stiffness as seen from the cutting module, excellent stress cracking resistance, impact strength and warp resistance compared to articles molded from high pressure polyethylene resin.

Table II

Resin properties

Index, melt flow (g / 10 min)

Density [kg / &lt;m³]

Ratio of flow rates

Product features cutting module] MPa] • crack resistance (time to failure) impact strength at -51 ° C [J] • warp resistance

Examples 4 to 7

The copolymers were prepared as described in Example 1. Table III is shown

Example 1 Example 2

20

<td> 925</td><td> 924</td>

<td> 25</td><td> 35</td>

<td> 282</td><td> 192</td>

<td>&gt; 21 days</td><td>3 minutes</td>

<td>28.25 (punctured)</td><td>6.79 (shattered)</td>

excellent very good comonomer which is reacted with ethylene to form a copolymer. The table also shows the melt index, density and flow rate ratio of the copolymers produced.

Table III

<td>Example</td><td>Komonomer</td><td>Melt flow index [g / 10 min]</td><td>Density [kg / rn ^]</td><td>Ratio of flow rates</td>

<td> 4</td><td>1-butene</td><td> 17,8</td><td> 928</td><td> 29</td>

<td> 5</td><td>propylene.</td><td> 19,2</td><td> 928</td><td> 25,5</td>

<td> 6</td><td>1-butene</td><td> 29</td><td> 925</td><td> 23</td>

<td> 7</td><td>• propylene butene (50/50)</td><td> 29</td><td> 927</td><td> 23</td>

Examples 8 to 11

Each of the polymers of Examples 4 to 7 are formed into bowls in an Impco injection molding machine (227 g) as described in Example 3. The cylinder temperature and minimum mold filling pressure are shown in Table IV. An overpressure of about 687 kPa above this minimum pressure is used. The impact toughness of the plates was measured as described in Example 3 at -40 and -50% C. The results are shown in Table IV.

The results show that products such as bowls formed from the copolymers of the invention have excellent impact toughness.

Table IV

<td>Example</td><td rowspan="2">Resin (example)</td><td>Shaping conditions</td><td>Impact strength []]</td>

<td></td><td>Cylinder temperature Minimum pressure</td><td>40 ° C-51 ° C</td>

<td></td><td></td><td> [^andO] to fill</td><td></td>

<td></td><td></td><td>molds (MPa!)</td><td></td>

<td> 8</td><td> 4</td><td> 260,2</td><td> 8,59</td><td colspan="2"> — 27,12</td>

<td> 9 '·</td><td> 5</td><td> 260,2</td><td> 8,59</td><td></td><td>(sample punctured) 24.86 '1'</td>

<td>¹⁰</td><td> 6</td><td> 205</td><td> 7,56</td><td> ' 33,96</td><td> 28,25</td>

<td> 11</td><td> 7</td><td> 205</td><td> 7,21</td><td colspan="2">(sample punctured) (sample punctured) 29.48 25.94</td>

(sample punctured) (sample punctured) &lt;! ·&gt; 2 samples out of 6 burst

Examples 12 to 15

Each of the polymers of Examples 4 to 7 are molded into caps in a Moslo (85 g) injection molding machine as described in Example 3. The cylinder temperature and minimum mold filling pressure are shown in Table V. An overpressure of about 824 kPa above this minimum is used. pressure. The lids were tested for stress cracking resistance in Crisco oil as described in Example 3. The results are summarized in Table V.

The results obtained show that products such as lids made from the copolymer of the invention have excellent stress cracking resistance.

Table V

Example Resin (example)

Shaping conditions

Cylinder temperature Minimum pressure [° C] for mold filling (MPa)

Resistance to stress cracking

<td> 12</td><td> 4</td><td> 260,2</td><td> 5,67</td><td>&gt; 21 days</td>

<td> 13</td><td> 5</td><td> 260,2</td><td> 5,67</td><td>&gt; 21 days</td>

<td> 14</td><td> 6</td><td> 260,2</td><td> 3,78</td><td>&gt; 21 days</td>

<td> 15</td><td> 7</td><td> 260,2</td><td> 3,78</td><td>&gt; 21 days</td>

Examples 16 to 23

The 1-butene copolymers of Examples 16 to 20 are prepared as described in Example 1. The comonomer used to produce the polymer, the density, the indeix melt flow, and the cutting modulus of the copolymers produced are shown in Table VI.

The high-pressure polyethylene resins of Examples 21-23 are commercially available under the designation PEP 231, 530 and 440 (Union Carbide Corporation).

<td colspan="5">Table VI</td>

<td>Example</td><td>Komonomer</td><td>Density [kg / m.3]</td><td>Melt flow index [g / 10 min]</td><td>Sectional module [MPa¹]</td>

<td> 16</td><td>1-butene</td><td> 918</td><td> 7,0</td><td> 220,5</td>

<td> 17</td><td>1-butene</td><td> 9.26</td><td> 12,0</td><td> 282,3</td>

<td> 18</td><td>l-butane</td><td> 928</td><td> 18,0</td><td> 333,9</td>

<td> 19</td><td>l-butane</td><td> 928</td><td> 30,0</td><td> 334,6</td>

<td> 20</td><td>l-butane</td><td> 937</td><td> 7,0</td><td> 480,9</td>

<td> 21</td><td> —</td><td> 919</td><td> 10,0</td><td> 130,5</td>

<td> 22</td><td> —</td><td> 924</td><td> 9,5</td><td> 171,7</td>

<td> 23</td><td> —</td><td> 926</td><td> 28,0</td><td> 199,2</td>

Examples 24 to 31

The resins produced according to Examples 16 to 23 are molded by rotary casting on a portion of the line to the heaters. The resin is ground to a powder which passes through a sieve aperture of 417 µm diameter and processed in a mold into a 178 X 178 mm cross-section, 610 mm long and 3.17 mm average thickness. The oven temperature is 305 ° C, the oven cycle time is 12 minutes except for Examples 18 and 19, where the cycle time is 8 minutes) and the mold is cooled for 3 minutes by spraying with cold water.

The moldability of each of the resins is monitored. At -40 ° C, the impact resistance of all samples was also measured using a 4.54 kg falling hammer tipped with a 25.4 mm diameter semicircular head. Hammer up¹ let it fall from a height of 710 mm.

The percentage of non-compliant samples is given in Table VI. Several of these rotary molded specimens also measure the resistance to repeated bending on a Ross rubber deflector, which makes 120 bends at 90 ° per minute. The mechanical stress cracking resistance is measured according to ASTM D 1693 by a strip-shaped bent sample test using 100: igepal at 50 ° C. The results are shown in Table VII.

The results show that at a comparable modulus and melt index, the parts produced by rotary casting of low pressure copolymer resins have significantly better low temperature impact resistance, repeated bending resistance and mechanical stress cracking resistance than the same high pressure resin parts.

<img file="CS213372B2_D0013.tif" />

Example Low pressure resins High pressure resins

<img file="CS213372B2_D0014.tif" />

<img file="CS213372B2_D0015.tif" />

<img file="CS213372B2_D0016.tif" />

<img file="CS213372B2_D0017.tif" />

<img file="CS213372B2_D0018.tif" />

<img file="CS213372B2_D0019.tif" />

<img file="CS213372B2_D0020.tif" />

<img file="CS213372B2_D0021.tif" />

<img file="CS213372B2_D0022.tif" />

<img file="CS213372B2_D0023.tif" />

<img file="CS213372B2_D0024.tif" />

<img file="CS213372B2_D0025.tif" />

<img file="CS213372B2_D0026.tif" />

<img file="CS213372B2_D0027.tif" />

<img file="CS213372B2_D0028.tif" />

co eo CM

<img file="CS213372B2_D0029.tif" />

<img file="CS213372B2_D0030.tif" />

<img file="CS213372B2_D0031.tif" />

<img file="CS213372B2_D0032.tif" />

<img file="CS213372B2_D0033.tif" />

<img file="CS213372B2_D0034.tif" />

<img file="CS213372B2_D0035.tif" />

<img file="CS213372B2_D0036.tif" />

<img file="CS213372B2_D0037.tif" />

<img file="CS213372B2_D0038.tif" />

<img file="CS213372B2_D0039.tif" />

<img file="CS213372B2_D0040.tif" />

<img file="CS213372B2_D0041.tif" />

<img file="CS213372B2_D0042.tif" />

<img file="CS213372B2_D0043.tif" />

<img file="CS213372B2_D0044.tif" />

Example 32

Table VIII

The 1-butane copolymer resins of Examples 16-20 are injection molded; for lids, which are then subjected to the above-described crack resistance test under mechanical stress in Crisco oil. After 21 days of immersion in Crisco oil, there are no cracks in the bent section. Under similar conditions, the high pressure resin of Example 3 cracked after 3 minutes.

Example 33

The 1-butene copolymer resins of Examples 17-19 are injection molded into the trays under the conditions set forth above and then tested for impact strength at -51 ° C as described above. None of the bits shatter. The plates are punctured using the energy shown in Table VIII. The dishes formed from the high pressure control resin of Example 3 were shattered at 6.79 J. The results are shown in Table VIII.

<td>Example resin</td><td>Impact toughness (J)</td>

<td> 17</td><td>35.05 (stroke)</td>

<td> 18</td><td>27.17 (Beating)</td>

<td> 19</td><td>28.25 (Thrust)</td>

<td> 3</td><td>6.79 (shattering)</td>

Example у 34 to 36

1-Butene copolymers were prepared as described in Example 1. Commercially available high pressure polyethylene DNDA 0180 (Union Carbide Corporation) was used as a control material. For comparison, the low pressure resin of Example 16, which has a higher melt index than both 1-butene copolymer and polyethylene, is also used.

3.17 mm test specimens (ASTM D-1928) are pressed from the resins and tested for resistance to cracking at 100% igepal. The bend specimen test according to ASTM D 1693 is used. The time at which 50 out of 20 molded specimens are cracked at 50 ° C is determined. The results are shown in Table IX.

Table IX

Example 34 35 36

<td>type of resin</td><td>copolymer</td><td>high pressure</td><td>copolymer</td>

<td></td><td>1-butene</td><td>polyethylene</td><td>Of 1-butene of Example 16</td>

<td>Melt flow index [g / 10 min]</td><td> 1,0</td><td> 2,0</td><td>⁷¹⁰</td>

<td>Density [kg / m³]</td><td> 921</td><td> 921</td><td> 918</td>

<td>Sectional module [MPa]</td><td> 263,12</td><td> . 158</td><td> 220,5</td>

Resistance to cracking under mechanical stress (hours to failure% of samples)&gt; 504 200&gt; 504

The results show that. although low pressure resins have about 50% higher modulus of high pressure resins and are therefore subjected to greater stress in the bent specimen test, they have significantly better mechanical stress crack resistance than high pressure resin produced in a stirred reactor, which is considered as one of commercially available polyethylenes having the highest resistance to cracking under mechanical stress. Although the melt flow index of the low pressure resin is increased to 7.0 as in Example 36, the low pressure resin is substantially more resistant to mechanical stress cracking than the high pressure resin having a melt flow index of 2.0. Increasing the melt flow index normally results in a reduction in cracking resistance under mechanical stress.