Carboxylate terminated polymers and their use in impact-modified plastics

The art relates to carboxylate-terminated polymers with specific Mooney and solution viscosities and the use of the polymers in impact resistant modified plastics such as impact resistant polystyrene (HIPS).

Specific impact resistance such as styrene-maleic anhydride copolymer (SMA's), impact resistant polystyrene (HIPS), methylmethacrylate-butadiene-styrene copolymer, transparent impact resistant polystyrene, acrylonitrile butadiene styrene copolymer Sex-modified plastics are typically prepared in the presence of rubber, such as polybutadiene or styrene-butadiene copolymers, to enhance toughness, impact strength and other properties. The low solution viscosity additive rubber can facilitate the dispersion of the additive rubber in the plastic phase. Further, in the initial stage of polymerization of HIPS, phase separation starts due to the immiscibility of rubber in the formed polystyrene and the depletion of the styrene phase. In addition, for SMAs, low solution viscosities can improve the clarity and gloss of the resulting product.

The low solution viscosity of the added rubber is highly desirable, but it makes commercial handling difficult. For example, low solution viscosities typically result in liquid or semi-liquid materials that are difficult to package and ship. Therefore, a substance having a relatively high volumetric viscosity that can be shipped and veiled into a shape that is easy to handle is desirable.

U.S. Pat. No. 7,105,613 by the same applicant discloses a polymerization technique that achieves a rubber formulation with a high volumetric viscosity and a low solution viscosity by means of a carboxylate terminator portion of the rubber polymer, which by reference. The whole is incorporated herein. This creates a veilable rubber formulation, which is useful as a plastic additive.

Nevertheless, further improved polymers for impact resistant modified plastics, such as polymers that contribute to the plastic to improve the Izod impact value, and the impact strength of the plastic composition used in reduced amounts. There is still a need for polymers that can influence the plastic. There is also a need for additives that can reduce the solution viscosity of the polymer while maintaining a high volumetric viscosity so that the polymer remains veilable. Further, an additive capable of facilitating control of glossiness and izod strength is also desirable.

<p><patcit num="1"><text>U.S. Pat. No. 7,105,613</text></patcit></p>

<p> The present disclosure relates to, in one embodiment, a composition comprising rubber derived from the polymerization of at least one conjugated diene in the presence of an anion initiator. The rubber has a carboxylate arrest portion derived from the use of carbon dioxide to terminate the polymerization reaction. The above rubber has a Mooney viscosity greater than about 35 (ML)₁₊₄) And a solution viscosity of X (where X is greater than about 75 cP). Further, by adding a viscosity reducing agent to the rubber, the solution viscosity of the rubber is lowered from X to Y so that Y is in the range of about 0.3X to about 0.58X.</p><p> The method of utilizing the carboxylate-terminated rubber described in the previous paragraph to prepare a blend of the rubber with an impact resistant modified plastic is as follows: (a) in a solvent containing at least one vinyl aromatic compound. The steps of melting the rubber stopped with the carboxylate, (b) optionally adding at least one additional monomer, and (c) so that Y is in the range of about 0.3X to about 0.58X. A step of adding at least one additive capable of reducing the solution viscosity of the rubber stopped with the carboxylate from X to Y, and (d) optionally adding at least one additional inert solvent. Polymerization of styrene is initiated by (e) optionally adding other additives selected from the group consisting of extender oils, modifiers, and antioxidants, and (f) the use and heating of initiators. This includes a step in which phase inversion occurs between the steps. The above steps (a), (b), (c), (d) and (e) can be performed in any order. However, it is preferable to perform step (c) before the phase inversion occurs. The impact-resistant modified plastic comprises impact-resistant polystyrene, styrene-maleic anhydride copolymer, methylmethacrylate-butadiene-styrene copolymer, transparent impact-resistant polystyrene, and acrylonitrile-butadiene-styrene copolymer. Selected from the group.</p><p> Compositions according to the techniques described herein have Mooney viscosities greater than about 35 (ML).₁₊₄) And a carboxylate-stopped rubber having a solution viscosity of X (where X is greater than about 75 cP). By adding a viscosity reducing agent, the solution viscosity is reduced from X to Y so that Y is in the range of about 0.3X to about 0.58X, and the rubber is at least in the presence of an anion initiator. It is derived from the polymerization of a kind of conjugated diene. Further, the composition comprises an impact-resistant modified plastic for blending with a carboxylate-stopped rubber, wherein the impact-resistant modified plastic is an impact-resistant polystyrene, a styrene-maleic anhydride copolymer. It is selected from the group consisting of methylmethacrylate-butadiene-styrene copolymer, transparent impact resistant polystyrene, and acrylonitrile butadiene styrene copolymer.</p><p> For the purposes of this disclosure, the terms "rubber" and "elastomer" are used interchangeably.</p>

The technique described in the present application is directed to a method for providing a blend of a composition and an impact resistant modified plastic having advantageous properties. To achieve this, it is described herein that a viscosity reducing agent reduces the solution viscosity of rubber in solution. Based on the type of viscosity reducing agent selected, the rubber may have different particle sizes and morphologies within the impact resistant modified plastic composition. Viscosity reducing agents also allow the purchaser of a single rubber sample to obtain potions with varying solution viscosities depending on the type and amount of viscosity reducing agent used. This can give the purchaser more flexibility and allow the buying and selling of large quantities of rubber, which can be accompanied by economies of scale.

In one embodiment of the present disclosure, the rubber is a polymer or copolymer having a carboxylate arrest moiety. The rubber has a relatively high Mooney viscosity of over about 35 and a solution viscosity of X, where X is greater than about 75 cP. After adding the viscosity reducing agent to the rubber or the composition containing the rubber, the dissolved viscosity thereof is lowered from X to Y in the solution so that Y is in the range of about 0.4X to about 0.58X.

In one embodiment, the blending of the carboxylate-stopped rubber with the impact resistant modified plastic (a) dissolves the carboxylate-stopped rubber in a solvent containing at least one vinyl aromatic compound. (B) Optionally, add at least one additional comonomer, and (c) add at least one viscosity reducer, thereby increasing the solution viscosity of the rubber from X to Y (where Y is about 0.4X to about 0.58). X), (d) optionally at least one additional inert solvent, and (e) optionally an addition selected from the group consisting of extender oils, modifiers, and antioxidants. It is prepared by adding the agent and (f) initiating the polymerization of styrene by the use and heating of the initiator, during which phase inversion occurs. Steps (a), (b), (c), (d) and (e) can be performed in any order, but step (c) can be performed before phase inversion occurs in step (f). preferable. Impact-resistant modified plastics blended with rubber include impact-resistant polystyrene, styrene-maleic anhydride copolymer, methylmethacrylate-butadiene-styrene copolymer, transparent impact-resistant polystyrene, and acrylonitrile-styrene-butadiene. Selected from the group consisting of copolymers.

For example, rubber that has been stopped with a carboxylate is CO as a lithium initiator and stop.₂It can be prepared by anionic polymerization using and. The rubber stopped by carboxylate is mainly described by the following equation:<chemistry num="1"><img file="JP2010514902A_D0001.tif" /></chemistry>Uncoupled polymers with (where the wavy line represents the polymer chain) can be included.

In addition, the rubber stopped by the above carboxylate has the following formula:<chemistry num="2"><img file="JP2010514902A_D0002.tif" /></chemistry>And / or<chemistry num="3"><img file="JP2010514902A_D0003.tif" /></chemistry>It can also include a di-coupling polymer and / or a tri-coupling polymer with.

The elastomer portion of the elastomer stopped with the above carboxylate is, for example, a conjugated diene rubber; a copolymer of a conjugated diene with a vinyl aromatic compound or a copolymerizable monomer such as a vinyl aromatic compound with less than 50% by weight. Copolymer; C₁~ C₈Elastic copolymer of alkyl (meth) acrylate with conjugated diene; C₁~ C₈Elastic copolymer of alkyl (meth) acrylate with butadiene and / or styrene; olefin rubber such as ethylene propylene copolymer (EPR) or ethylene-propylene-diene monomer rubber (EPDM); ethylene-vinyl acetate rubber C of elastomer₁~ C₈Alkyl (meth) acrylate; or combinations comprising at least one of the above elastomers is included.

Specific examples of conjugated diene monomers that can be used to make the rubber are 1,3-butadiene, isoprene (2-methyl-1,3-butadiene), piperylene (1,3-pentadiene), methyl-1, 3-Petandien, 2,3-dimethyl-1,3-butadiene, 2-methyl-1,3-pentadiene, 2-ethyl-1,3-pentadiene, 3-methyl-1,3-pentadiene, 4-methyl- In addition to 1,3-pentadiene, 2,4-dimethyl-1,3-pentadiene, 1,3-hexadiene, 2,4-hexadiene, 1,3-heptadiene, etc., at least one of the above-mentioned conjugated diene monomers. Is a mixture containing.

For some applications, homopolymers of conjugated diene may be preferred, but copolymers containing at least one conjugated diene may be highly desirable. The comonomer can be a vinyl array containing a vinyl aromatic compound having an alkyl group, an aralkyl group or a cycloalkyl group bonded to an aromatic nucleus, preferably having 20 or less carbon atoms.

In one embodiment, the carboxylate-stopped rubber comprises a conjugated diene copolymerizing with one or more comonomer, such as vinyl aromatic compounds. Examples of suitable vinyl aromatic monomers that can be used are styrene, 3-methylstyrene, vinyltoluene, ethylstyrene, 3,5-diethylstyrene, 4-n-propylstyrene, α-methyl-styrene, α- Methylvinyl toluene, α-chlorostyrene, α-bromostyrene, dichlorostyrene, dibromostyrene, tetra-chlorostyrene, p-cyclohexylstyrene, vinylnaphthalene, 1-vinylnaphthalene, 2-vinylnaphthalene, methoxystyrene, t-butoxystyrene , Vinyl ethylnaphthalene, vinylmethylnaphthalene, vinylbutylnaphthalene, vinyldiphenyl, vinyldiphenylethane, 4-vinyl-4'-methyldiphenyl and the like, as well as combinations containing at least one of the above-mentioned compounds. Styrene and / or α-methylstyrene may be used as a copolymerizable monomer with the conjugated diene monomer.

When such comonomer is used, the resulting copolymer generally comprises from about 10% to about 70% of units from the comonomer, 30-40% or less in other embodiments.

Carboxylated rubbers composed of polymers and copolymers of conjugated diene such as polybutadiene, polyisoprene and styrene-butadiene rubber are particularly suitable for the applications described in the present application.

The weight average molecular weight (Mw) and number average molecular weight (Mn) can be determined by gel permeation chromatography (GPC), which GPC is known as size exclusion chromatography (SEC). (Molecular weights expressed in this application have been corrected for polybutadiene using the appropriate Mark-Hawink constants for polystyrene standards.) Avoid undesired material properties for rubbers stopped at a constant carboxylate. The molecular weight should be well controlled so that it can be done. For example, polydiene such as low Mw polybutadiene may be difficult to handle and process at ambient temperature. In one embodiment, the Mw of the carboxylated rubber of the present disclosure is from about 80,000 to about 350,000, or from about 100,000 to about 300,000, and in other embodiments from about 140,000 to about 200,000.

The solution viscosity of the above carboxylate-stopped rubber can be optimized to suit a particular application. The low solution viscosity rubber can provide advantages such as facilitating the dispersion of the rubber in the plastic phase and improving the transparency and glossiness of the resulting product in the impact resistant modified plastic composition. it can.

In one embodiment, the solution viscosity of the rubber stop with carboxylate before adding the viscosity reducing material is generally in the range of about 75cP to about 300cP, or about 80cP to about 250cP, or about 90cP to about 170cP. Can be done. Solution viscosity can be measured in a variety of ways. The solution viscosities described herein were measured using a 5.43% toluene solution at 25 ° C.

Viscosity reducing agents, i.e. ionolizers, can be used in conjunction with carboxylate-stopped rubbers to provide added rubbers with the desired solution viscosity. Examples of these viscosity reducing substances are, but are not limited to, zinc stearate, zinc oxide, aluminum stearate (mono, di or tristeert), and / or organics such as 2-ethylhexanoic acid (EHA). Acids / salts can be mentioned. The viscosity reducing agent can be added to the rubber before or after mixing the rubber with the impact resistant modified plastic. However, adding the viscosity reducing agent to the rubber before the phase inversion occurs allows for better dispersion of the viscosity reducing agent in the rubber. In one embodiment, the viscosity reducing agent can be dissolved in a styrene monomer for HIPS production with a carboxylated rubber. Different viscosity reducing agents can result in different particle sizes and morphologies of the rubber in the HIPS product. The weight ratio of such viscosity reducing agent to the carboxylate-stopped rubber can generally be in the range of about 0.1% to about 10%, or about 0.2% to about 5%, or about 0.25% to about 3%. ..

When a viscosity reducing agent is added, the rubber stopped with carboxylate will reduce the solution viscosity, and generally, the viscosity reducing agent is added from about 0.3 times the solution viscosity (X) of the elastomer before adding the viscosity reducing agent. It ranges from about 0.58 times the solution viscosity (X) of the previous elastomer. In one embodiment, the carboxylate-stopped rubber generally has a reduced solution viscosity in the range of about 0.4X to about 0.58X, and in other embodiments it has a reduced solution viscosity in the range of about 0.45X to about 0.55X. In one embodiment, the final solution viscosity of the rubber stopped with carboxylate after adding the viscosity reducing agent is in the range of about 30 cP to about 174 cP, or in some embodiments from about 43 cP to about 120 cP. Is the range of.

In one embodiment, the carboxylate-stopped rubber is a material having a Mooney viscosity that can be shipped and veiled into an easy-to-handle shape. Mooney viscosity is measured according to ASTM D-1646. ML₁₊₄Refers to the Mooney viscosity at 100 ° C. Unless otherwise specified, the Mooney viscosity referred to here is ML.₁₊₄Is. The Mooney viscosity of rubber arrested with carboxylate can generally range from about 35 to about 75, preferably from about 45 to about 65.

In other embodiments, carboxylate-stopped rubbers such as carboxylate-stopped polybutadiene are used as additives in impact-resistant modified plastic compositions (resins) such as HIPS, ABS, SMA and TIPS. .. Based on the total weight of the plastic composition, carboxylated rubber in an amount of about 5 to about 30 weight percent, or about 5 to about 25 weight percent, or about 6 to about 20 weight percent of the composition. Can be added.

The carboxylate-stopped rubber can be dispersed in the plastic matrix and exist as substantially separated particles. The size of the particles can generally range from about 0.1 micron to about 10 microns, or from about 0.2 micron to about 3.0 microns. Its particle size can be measured using a transition electron microscope (TEM).

To give an example of the techniques described herein, continuous diblock polymers with carboxylate arrests could be prepared and used in HIPS or ABS. Examples of such continuous diblock polymers include, but are not limited to, polymers containing vinyl aromatic hydrocarbons and alkenes. More specific examples include styrene-butadiene copolymers such as copolymers containing about 10% bonded styrene, styrene-isoprene copolymers, or styrene-isoprene-butadiene copolymers. The use of comonomer will extend the range of solution viscosities while still allowing the polymer to be veiled.

One method of producing an impact resistant modified plastic composition comprising rubber stopped with carboxylate is generally: (i) prepare a living polymer by anionic polymerization and (ii) stop the living polymer with carboxylate. And (iii) include incorporating the carboxylate-stopped rubber into the plastic composition.

Rubber stopped with carboxylate can be continuously processed by a bulk method, an emulsion method, a suspension method, a solution method, or a composite method such as a bulk-suspension technique, an emulsion-bulk technique, a bulk-solution technique, or another polymerization technique. , Semi-batch method, or batch method can be used for polymerization.

Any suitable anion initiator can be used in the preparation of the carboxylated rubber. Examples of anion initiators include alkali metal organometallic compounds. Other suitable anion initiators include activated organometallic compounds of Group II metals. For example, dialkylmagnesium was activated with a Group I metal alkoxide.

In one embodiment, the anion initiator is an organolithium compound. Organolithium initiators are known to form living polymerization reactions. As is known to those of skill in the art, living polymerization is useful for adding end groups to form clear blocks of monomers in the polymer chain. Suitable lithium initiators are not particularly limited, but are n-butyllithium, sec-butyllithium, tert-butyllithium, 1,4-dilithiobutane, 1,3- (di-2- (2-lithio-4-). Includes both methyl) pentenyl) benzene and mixtures thereof.

The anion initiator is used in an amount designed to give the desired molecular weight of the resulting polymer.

A high vinyl content of the rubber arrested with carboxylate may be desirable. In that case, for example, to increase the reaction rate, equalize the reactivity ratio of the monomers, and / or control the 1,2-vinyl content or 1,2-microstructure in the conjugated diene unit. , Modulators or 1,2-microstructure regulators may be used for anionic polymerization. Examples of suitable modifiers include, but are not limited to, triethylamine, tri-n-butylamine, hexamethylphosphate triamide, N, N, N', N'-tetramethylethylenediamine, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene. Glycol dimethyl ether, tetraethylene glycol dimethyl ether, tetrahydrofuran, 1,4-diazabicyclo [2.2.2] octane, diethyl ether, tri-n-butylphosphine, p-dioxane, 1,2 dimethoxyethane, dimethyl ether, methyl ethyl ether, ethyl propyl Ether, di-n-propyl ether, di-n-octyl ether, anisole, dibenzyl ether, diphenyl ether, dimethylethylamine, bis-oxalanylpropane, tri-n-propylamine, trimethylamine, triethylamine, N, N-dimethyl Aniline, N-ethylpiperidine, N-methyl-N-ethylaniline, N-methylmorpholin, tetramethylenediamine, oligomeric oxolanylpropane (OOPs), 2,2-bis- (4-methyldioxane), bistetrahydro Frill propane, bis (2-oxolanyl) methane, 1,1-bis (2-oxolanyl) ethane, 2,2-bis (2-oxolanyl) propane, 2,2-bis (5-methyl-2-oxolanyl) propane , 2,2-bis- (3,4,5-trimethyl-2-oxolanyl) propane, 2,5-bis (2-oxolanyl-2-propyl) oxolane, octamethylperhydrocyclotetraflufreelene (cyclic four) Quantum), 2, 2-Bis (2-oxolanyl) butane and the like are included. It is also possible to use two or more modifiers or a mixture of 1,2-microstructure control agents.

Suitable polymerization can be carried out in an autoclave, pressure reactor or bottle capable of withstanding the pressure generated at the temperature of use. In one embodiment, the pressure generated during the polymerization will be in the range of about 34 to about 760 kPa. Temperatures can range from almost room temperature to about 120 ° C. The polymerization time is not particularly limited, but can be continued as long as necessary until the reaction is completed and the desired degree of polymerization is obtained.

If the polymerization is completed to the desired degree, CO in the reaction system₂May be added. CO₂Terminates the living polymer chain, resulting in a carboxylate end group for most of the polymer chain. CO₂CO in the polymerization mixture by allowing it to foam and pass through in the form of a gas.₂Can be added. CO₂Reacts with the reactive end groups of the living polymer chain to effectively terminate the living polymerization. The resulting polymer contains a carboxylate end group.

A small amount of an antioxidant such as di-t-butyl cresol may be added to the polymer product. Antioxidants can be added in an amount of less than 4 weight percent or less than 2 weight percent of the total solution. The polymer can be recovered and dried prior to processing, preferably by drum drying at a temperature suitable for evaporation of the remaining solvent. Alternatively, the polymer product is recovered using a vapor desolvation method.

In one embodiment of the present disclosure, the carboxylated rubber is incorporated into the plastic composition. The plastic composition can be prepared by dissolving the carboxylated rubber in a solution containing a vinyl aromatic monomer such as styrene and polymerizing the resulting mixture. This method can be performed using conventional techniques known in the field of preparing impact resistant modified plastics such as rubber reinforced HIPS and ABS, US Pat. Nos. 2,646,418, 4,311,819, 4,409,369 and It is described in No. 5,721,320. For example, HIPS is produced by polymerizing styrene in the presence of rubber arrested with about 5% to about 40% dissolved carboxylate or rubber arrested with about 6% to about 20% carboxylate. be able to. Mixing of carboxylate-stopped rubber with impact-resistant modified plastics may be achieved during free radical polymerization, which is carried out in batch cells, bulk continuous, suspensions, solutions, or emulsions. be able to. For example, ABS copolymers can be made using polymerization methods such as bulk-suspension, continuous bulk, emulsion and the like.

For example, the carboxylated rubber is blended with a polymerized vinyl aromatic monomer. In another example, the vinyl aromatic monomer is polymerized in the presence of carboxylated rubber. In the latter method, the vinyl aromatic monomer may be partially graft-polymerized on a carboxylate-stopped rubber, where a free radical initiator may be used.

For HIPS, the techniques disclosed herein are that the reduced solution viscosity after the addition of the viscosity reducing agent can result in a reduced particle size and improved dispersion of the polymer in the vinyl aromatic domain. Provides an improvement over typical HIPS polymers. This can result in improved physical and optical properties.

The examples disclosed herein can be used for efficient and economical production of HIPS, due to their ease of molding, excellent glossiness, and generally excellent mechanical properties, electric refrigerator linings, packaging. Widely used in many applications such as furniture, home appliances, toys, etc. HIPS is mainly produced by the continuous polymerization method, but can also be produced by the batch method.

An example of a continuous method for producing HIPS consists of polymerizing a styrene monomer in the presence of melted rubber. Polystyrene is first formed from styrene monomers in a homogeneous rubber solution. Types of rubber commonly used in the production of HIPS include polybutadiene (PB), styrene-butadiene rubber (SBR) and styrene-butadiene-styrene rubber (SBS). The above method may utilize two continuous stirred tank reactors (CSTR) in the first production method to control the grafting of elastomer and styrene particles and the rubber particle size (RPS). In this method, one of the CSTRs can function as a plain version reactor (PIR), where the reaction solution is at the rubber / styrene inversion point, i.e. the reacting solution is in a rubber / styrene monomer matrix. It is maintained at a point before the point where the polystyrene particles become rubber particles in the polystyrene matrix. In the second CSTR container, the inversion point may be reached.

Articles made with the disclosed examples of plastic compositions can exhibit mechanical properties such as improved impact resistance. Generally, the Izod impact strength of such articles is about 0.5 or more or 1.5 or more, and an Izod value of about 1.5 to about 4.0 can be used for a particular application, but the Izod strength is relative to the gloss properties. Low Izod values are acceptable for some applications where glossiness is important due to the opposite phase. Such an izod value is, for example, in the range of about 1.0 to about 2.5. Izod strength can be measured using ASTM method D-256-06.

Other mechanical and rheological properties of impact resistant modified plastic compositions such as HIPS are affected by the properties of the rubber phase. In this regard, some of the properties of rubber that can be modified to control overall HIPS performance are, among other things, the concentration of rubber particles dispersed in the HIPS resin, grafting and cross-linking ability, rubber particles. Examples include rubber morphology such as shape and size, rubber particle size distribution (RPSD), swelling index, and rubber phase volume measured by the ratio of% gel to% plastic. For example, a viscosity reducing agent can be used to control the size of the rubber particles in the impact resistant modified plastic blend. By changing the size of the rubber particles, it becomes possible to control the izod strength and glossiness of the resulting impact-resistant modified plastic blend.

The following examples are given to provide additional guidance to those skilled in the art in carrying out the claimed invention. The examples provided are merely representative of the workpieces that contribute to the teachings of the present application. Therefore, those examples are not intended to limit the invention in any way, but are defined in the appended claims.

<p>I. Elastomer synthesis A. Example Elastomer AD (rubber stopped with carboxylate)<u style="single">Example Elastomer A</u> Two 50 gallon reactors were used. Hexane was charged into the first reactor and the reactor was heated to 210 ° F using a reactor jacket. Next, hexane (feed rate 51.99 lbs / hr), 1,3-butadiene (22% in hexane) (feed rate 227.27 lbs / hour), oligomeric oxalanylpropane (OOPs) (0.020 lbs / hr, in hexane). 15%, syringe pump) and gelation inhibitor (1,2-butadiene, 5% in hexane) (feed rate 0.125 lbs / hr) were continuously charged into the first reactor. A second supply of hexane (feed rate 33.24 lbs / hr) was charged into the reactor along with a supply of n-butyllithium (2.2 lbs / hr, 3% in hexane). As the reaction proceeded, the jacket temperature was lowered to 175 ° F and the top of the reactor was kept at a maximum temperature of about 200 ° F. The residence time of the reactor was about 51 minutes. The polybutadiene product was transferred from the top of the first reactor and fed into the second reactor. This resulted in 48,000 basic Mn. Mn measured after coupling increased as reported in Table 1. CO in the second reactor at a rate of about 0.2 lbs / hour₂Was added to couple and stop the polybutadiene to give an elastomer stopped with carboxylate. The residence time of the second reactor was about 51 minutes.</p><p><u style="single">Example Elastomer B</u> For Example B, the same method as described for Example A was performed, except that the supply rate of n-butyllithium was 2.0 lbs / hr for the first supply. CO₂The supply rate was the same as in Example A. This gave a polymer with a base Mn of about 51,600.</p><p><u style="single">Example Elastomer C</u> For Example C, the supply rate of n-butyllithium was set to 1.8 lbs / hr for the first supply, and CO₂The same method as described in Example A was performed, except that the supply rate was about 0.1 lbs / hr. This gave a polymer with a base Mn of about 60,400.</p><p><u style="single">Example Elastomer D</u> For Example D, the supply rate of n-butyllithium was 1.5 lbs / hr for the first supply, and CO₂The same method as described in Example A was performed, except that the supply rate was about 0.1 lbs / hr. This gave a polymer with a base Mn of about 70,000.</p><p> Table 1 shows the properties of the synthesized carboxylated elastomer.</p><p><tables num="1"><img file="JP2010514902A_D0004.tif" /></tables></p><p>B. Elastomer synthesis of Comparative Example AB (elastomer not stopped by carboxylate)<u style="single">Comparative example A</u> For the polybutadiene that does not stop at the carboxylate of Comparative Example A, a commercially available polybutadiene sold by Firestone Polymers Co., Ltd. (Akron, Ohio) under the trade name of Diene® 55 was used. (Two types of Diene 55, AC-10 and AC-15 are available and can be used interchangeably for comparative purposes.) The characteristics of Diene® 55 are shown in Table 1 above.</p><p><u style="single">Comparative example B</u> CO₂Polybutadienes that were not stopped with carboxylate were prepared according to the method described in Example Elastomer A, except that dioctyl terephthalate was added at a rate of 27.71 ml / hr instead of.</p><p> The characteristics of the obtained polybutadiene that is not stopped by the carboxylate are shown in Table 1 above.</p><p>II. Preparation of blends with impact resistant modified plastics (Examples 1-28) Various blends of pre-prepared carboxylate-fastened elastomers (Example AD) with carboxylate-non-fastened elastomers (Comparative Examples A and B) with impact-resistant modified plastics of the elastomers were used. Prepared. Table 2 shows the various combinations of elastomers and ionolizers used in the examples. For the purposes of this example, the impact resistant modified plastic prepared was HIPS. These examples should never be construed to limit the scope of this disclosure or claims to the use of HIPS as impact resistant modified plastics. A variety of other impact-resistant modified plastics are well known, and the means of preparing blends with the carboxylate-terminated elastomers disclosed herein are within the knowledge of one of ordinary skill in the art.</p><p><tables num="2"><img file="JP2010514902A_D0005.tif" /></tables></p><p> Examples of HIPS blends were prepared with the following formulations. Elastomer (rubber) 48-64 grams Styrene (solvent) 736 ~ 752 grams Ethylbenzene (additional solvent) 141.2 grams 20 grams of mineral oil I-1076 (Irganox 1076 Antioxidant, Ciba) 8.4 grams-10% hexane solution added Tertiary Butyl Benzoart (Initiator) 0.15g</p><p> In this way, the total solution volume for a typical batch was 800 grams (combined with styrene + elastomer). Some examples contained more or less rubber. This resulted in a rubber concentration in the solution of about 7-20%. The desired rubber concentration in HIPS was 8-10%. The expected final conversion of styrene was expected to be about 70%, but it varied from case to case, as reported in the "Styrene conversion" column of Table 4 below.</p><p> A 1.5 liter coated glass reactor equipped with a spiral stirrer was utilized to prepare the HIPS blend. The stirrer had a maximum rpm of 180.</p><p> Generally, in order to prepare a composition, a specific amount of polybutadiene was dissolved in styrene and charged into the above reactor. Ethylbenzene was then added with additional ingredients including mineral oil, antioxidants, initiators and ionolizers (if applicable). The jacket was set to 100 ° C. when these components were charged into the reactor. After adding the component, the stirrer was operated (set to 180 rpm). In order to keep the reaction rate almost constant, the jacket temperature was raised from 102 ° C to 160 ° C during the course of polymerization, and the rpm of the stirrer was lowered during the course of polymerization (30 rpm from the initial setting of 180 rpm). Down to). The total reaction time (in the reactor) was 6.5 hours. Various amounts of HIPS compositions were made. The HIPS composition was dried in a vacuum oven at a temperature of 240 ° C. for 45 minutes to remove the residual solvent and monomer and cause rubber cross-linking. Table 3 shows detailed setting examples of reaction conditions generally applicable to each of Examples 1 to 28 below. Some variation of the described parameters occurred between each example.</p><p><tables num="3"><img file="JP2010514902A_D0006.tif" /></tables></p><p>III. Analysis of HIPS composition (Examples 1-28) Various HIPS compositions (Examples 1-28) were analyzed and their properties determined. The results are reported below in Tables 4-1 and 4-2.</p><p> The above example was injection molded in a Battenfeld injection molding machine for testing. Tensile strength was measured with an Instron device. Izod strength was tested with an Izod impact tester. The conversion rate of styrene is expressed as a weight percentage of the total styrene. The rubber content and polydiene content are expressed as a weight percentage of the weight of the HIPS example.</p><p> The gel and swelling values were determined by immersing the above example in toluene at 60 ° C. for 2 hours, discarding excess toluene, and then centrifuging to separate the insoluble rubber moiety. The weight of the swollen rubber particles was measured. The sample was then dried in a vacuum oven at 210 ° C. and the weight of the dried rubber particles was weighed. The weight of dry rubber particles, the weight of HIPS, and the weight of swelling rubber were used to obtain gel and swelling values.</p><p><tables num="4-1"><img file="JP2010514902A_D0007.tif" /></tables></p><p><tables num="4-2"><img file="JP2010514902A_D0008.tif" /></tables></p><p> As the results in Tables 4-1 and 4-2 show, the balance between the strength and gloss properties of the impact resistant modified plastic can be controlled by using the viscosity reducing agent. For example, Examples 20 and 21 of HIPS showed a good balance of Izod strength and high gloss (&gt; 80). Examples 19, 23 and 24 showed fairly high gloss (about 60) and high Izod strength.</p>