Starch degradation/graft polymerisation composition, process, and uses thereof

The present invention relates to starch / polymer Pfropfemulsionen. More particularly, the invention relates to the production of such emulsions using persulfate salts to the starch substantially simultaneously dismantle and initiate polymerization.

often it is desirable to modified in coatings, adhesives and applications in the graphic with strength to use polymers. By combining starch with synthetic polymers by Graft copolymerization can be products with particularly desirable generate combinations of properties. See U.S.-P-3 640,925 and 4,171,407.

at special applications, it is particularly desirable that certain Metal ions such as iron, nickel, manganese, cerium and Copper, are not present, since they tend to be the resulting discoloring products. This is a particular problem in products in the graphics be used, as well as in the art of coating compositions for products such as binders for Ink and coating binders. In contrast, it is known that such Metals typically in systems of Stärkepfropfemulsion / copolymer either to degradation of starch or to facilitate the polymerization.

On Another issue arises in connection with the execution of the batch Graft. Often that is a group of conditions for the Degradation of the starch set (for example to modify their viscosity and other characteristics) after which a different set of conditions for the graft polymerization shall apply. A change the reaction conditions can lead to excessive processing times. Furthermore are often the reactants used in the mining process are unnecessary in the subsequent graft copolymerization or undesirable.

from that let yourself found that a need for improved stabilized with starch Polymer emulsions and methods for their preparation consists.

The Objects of the present invention therefore include providing an emulsion polymer of the following kind: <ul><li>(A) it has the desired viscosity and other characteristics; </li><li>(B) it can be be prepared in a process in which substantially the Alike for the degradation of the starch as for polymerizing the emulsion to be applied;</li><li>(C) there are used environmentally friendly and cost-effective components; and</li><li>(D) it is for a big suitable number of applications.</li></ul>

These and still other objects and advantages of the present invention will become apparent from the following description.

Short Summary the invention

The present invention is directed to a composition comprising is capable of a stabilized starch to produce polymer emulsion and directed to one having Strength stabilized polymer emulsion. In the composition are included: 5% to 30% total solids of a starch, 1% to 5.% Total solids by weight. Weight a persulfate salt, and at least 70 wt.% of total solids an ethylenically unsaturated Monomer. The remainder of the emulsion is water.

The grants present invention also a method for producing a stabilized starch polymer emulsion, characterized by the steps that one with the strength the composition described above by the persulfate salt can degrade with the composition described above; and Meanwhile at least some of the starch, to be still degraded by the persulfate salt, ethylenically unsaturated Monomer / unsaturated Monomers to the degrading starch be added to cause the degrading starch a Is subjected to graft copolymerization with the monomers.

The grants present invention also a coating, characterized by 10% to 90% of the total solids weight. a starch stabilized Polymer emulsion comprising 5% to 30 wt.% Of total solids a starch, 1% to 5 wt.% Of total solids of a persulfate salt, and at least 70 wt.% Of total solids of an ethylenically unsaturated Monomer and 10% to 90 wt.% Of total solids of a pigment.

&lt;?page 3?&gt;

The grants present invention also, an ink composition characterized by 10% to 90 wt.% Of total solids of a starch stabilized polymeric emulsion, comprising 5% to 30% of total solids of a starch, 1% by weight. to 5 wt.% of total solids of a persulfate salt, and at least 70 wt.% Of total solids of an ethylenically unsaturated Monomer and 10% to 90 wt.% Of total solids of a pigment.

Detailed Description of the Invention

The present invention is directed to a composition comprising is capable of a starch stabilized to produce polymer emulsion, and refers to such a starch stabilized Polymer emulsion. In the composition are included: 5% to 30 wt.% Of total solids of a starch, 1 to 5 wt.% Of total solids a persulfate salt, and at least 70 wt.% of total solids an ethylenically unsaturated Monomer. The remainder of the emulsion is water.

In addition, in the composition comprises between 0.5% and 1 wt.% monomer solids be incorporated a surfactant. Such a surfactant is selected from the group consisting of anionic surfactants and nonionic surfactants. Typically, the ethylenically unsaturated monomer is selected from the group consisting of acrylic acid, Acrylates, methacrylates and styrenes. In the composition can additionally a pigment be incorporated.

The Composition of the present invention is preferably substantially free of iron. Preferably, the composition according to the invention is substantially free of iron, nickel, manganese, cerium and copper.

The This invention is also directed to a method for Producing a starch stabilized Polymer emulsion and includes the steps of: a) the strength can degrade using a persulfate salt and meanwhile b) at least a portion of the still to be degraded by the persulfate Strength impose at least one ethlyenisch unsaturated monomer to the degrading Strength, to cause that the depleting strength of a graft copolymerization is subjected to the / monomer (s). In a preferred method is the first of to be added as part of the process of monomers not earlier than 15 minutes and not later added than 30 minutes after the start of degradation of the starch.

Furthermore The present invention is directed to a coating. In such a coating are included: 10% to 90 wt% of total solids. a starch stabilized Polymer emulsion and 10% to 90 wt.% Of total solids of a pigment. The starch stabilized Polymer emulsion comprises or is prepared from:. 5% to 30% by weight of the total solids, a starch, 1% to 5 wt.% Of total solids of a persulfate salt, and at least 70 wt.% Of total solids of an ethylenically unsaturated Monomer. In preferred embodiments, are included in the coating. 10% to 20 wt% of total solids a starch stabilized Polymer emulsion and 80% to 90 wt.% Of total solids of a pigment. The ethylenically unsaturated monomer selected from the group consisting of acrylic acid, acrylates, methacrylates and styrenes.

In the starch stabilized Polymer emulsion can Further, between 0.5% and 1 wt.% monomer solids of a surfactant be included. This surfactant is selected from the group consisting of anionic surfactants and nonionic surfactants.

The starch stabilized Polymeric emulsion is preferably essentially free of iron and preferably essentially free from not only iron, but also nickel, manganese, cerium and Copper. additionally are in the coating at least one additive incorporated as for example, defoamers, Wetting agents, thickeners, bases, ammonia and water.

The This invention is also directed to an ink composition. included in such an ink composition are: from about 10% to 90 wt.% Of total solids of a starch stabilized emulsion polymer and 10% to 90 wt.% of total solids of a pigment, and preferably 10% to 20% of total solids of a starch stabilized polymeric composition weight. and 80% to 90% of the total solids weight. pigment.

In a starch stabilized Polymer emulsion are included. 5% to 30 wt% of total solids of a Strength, 1% to 5% of the total solids, a persulfate salt, and at least wt. 70 wt.% Of the total&lt;?page 4?&gt;solid materials an ethylenically unsaturated Monomer. In such a starch stabilized Polymer emulsion may further between 0.5% and 1 wt.% monomer solids of a surfactant included be. The strength in the stabilized Polymer emulsions for use in the ink compositions usable ethylenically unsaturated Monomers are preferably selected from the group consisting of acrylic acid, Acrylates, methacrylates and styrenes.

The in the ink compositions according to the invention starch stabilized usable Polymer emulsions are preferably substantially free of iron and also preferably substantially free of nickel, manganese, cerium and Copper. About that addition, in the ink compositions of the invention Additives to be included, such as defoamers, wetting agents, Thickeners, bases, ammonia and water.

In granted to one of the aspects The present invention provides a composition which is suitable for a starch stabilized to produce polymer emulsion. It comprises:. 5% to 30% by weight of Total solids, a starch, 1% to 5% of the total solids, a persulfate salt, and at least wt. 70 wt.% Of total solids of an ethylenically unsaturated Monomer. Optionally, a surfactant and / or chain transfer agent be included.

The The composition is preferably substantially free of iron, nickel, Manganese, cerium, and copper (for example, with less than 50 ppm in total, and less than 25 ppm iron).

Examples suitable strengths for use are starches such as hydroxyalkylated starch, oxidized starch, with modified acid Strength and cationic starch. Specific examples of hydroxyalkylated starch conclude hydroxyethylated corn starch and hydroxyethylated potato starch. The most preferred Strength is a hydroxyethylated corn starch such as Penford 230 (Penford Products Co., Cedar Rapids IA). Preferred starches used in the present invention is applied, are those which have been previously degraded.

Examples of suitable Persulfate salts are ammonium, potassium, sodium and Litihiumpersulfat.

The ethylenically unsaturated monomers any ethylenically unsaturated Monomer or class of monomers be. Examples are acrylate esters and acids, Methacrylate esters and acids, acrylonitriles, Methacrylonitrile, vinyl aromatic compounds, such as Styrene, substituted styrenes, vinyl esters of organic acids such as For example, vinyl acetate, acrylamides and methacrylamides.

Specific Acrylate esters and acids conclude a, without limited to these to be: acrylic acid, Methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, hexyl acrylate, tert-butyl acrylate, Lauryl acrylate, tert-butyl acrylate, 2-hydroxyethyl acrylate and hydroxypropyl acrylate. Also included are other substituted acrylic acids, such as for example, crotonic, maleic and itaconic as well as their esters.

Specific Methacrylate esters and acids conclude a, without limited to these to be: methacrylic acid, Methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate, Hexyl methacrylate, isobutyl methacrylate, isopropyl methacrylate, 2-hydroxyethyl methacrylate and hydroxypropyl methacrylate.

Specific vinyl aromatic compounds include, but are not limited to: Styrene, α-methylstyrene, p-methylstyrene, vinyltoluene, tert-butylstyrene and vinyl benzyl chloride.

Specific Vinyl esters of organic acids conclude a, without limited to these to be: vinyl acetate and vinyl versatate.

Specific Acrylamides and methacrylamides include, but are not limited to: Acrylamide, 2-acrylamido-2-methylpropanesulfonic acid, N- (isobutoxymethyl) acrylamide, n-butoxymethyl acrylamide, n-butylacrylamide, Diacetone acrylamide, N, N-dimethylaminoethyl acrylamide, N-methylolacrylamide, N, N-methacrylamide, n-methyl methylacrylamide, Isobutoxymethacrylamid and dimethylaminoethylmethacrylamide.

Other Close useful monomers the above-mentioned esters, amides and vinyl aromatic compounds, in which the substituting group to more than one polymerizable Group is attached, such as trimethylolpropane and methylenebisacrylamide. Other useful bifunctional monomers are divinylbenzene, ethylene glycol and hexanediol. It can also Mixtures of the various monomers to produce graft copolymer be used.

&lt;?page 5?&gt;

Especially preferred monomers are acrylic monomers such as acrylic acid and Esters of acrylic acid, such as ethyl acrylate, 2-ethylhexyl acrylate and methyl acrylate. The most preferred ethylenically unsaturated monomers are n-butyl acrylate, Methyl methacrylate, methacrylic acid and styrene.

to support the polymerization can also be added to a chain transfer agent, such as butyl mercaptopropionate. The role of the chain transfer agent is the molecular weight of the emulsion polymer prepared to regulate. Other chain transfer agents, enable this feature, those skilled in the art of emulsion polymerization is also known, for example Isooctylmercaptopropionat and tert-dodecyl mercaptan.

provided reach surfactants used are anionic surfactants, the preferred surfactants and nonionic surfactants. See generally, US-P-5358 998 and McCutcheon's Emulsifiers and Detergents, MC Publishing Co., edited 1995th Other representatives of surfactants such as cationic surfactants and zwitterionic surfactants may also be used. Preferred surfactants include sodium lauryl sulfate and Tergitol^® from Union Carbide a. The latter is a nonionic surfactant, the secondary comprises alcohol ethoxylates having a chain length of from 11 to 15 carbon atoms have.

In Alternatively, granted the invention provides a method for producing a starch stabilized Polymer emulsion. The aforementioned composition can be a starch / graft copolymer emulsion copolymerize.

In yet another embodiment, granted the invention provides a starch stabilized Emulsion, which is produced by the aforementioned process.

In of the present invention, the polymer typically using the method of emulsion polymerization, in which earlier polymerizing a mixture of ethylenically unsaturated and copolymerizable monomers in the presence of an aqueous Reaction medium, a surfactant and a free radical initiator were involved. The aqueous The reaction medium is the liquid, in dispersing the various components in an emulsion state are and the predominant character composed of water.

alternative can be required under the doctrine known surfactant replaced by additional starch.

The Method for the preparation of starch graft copolymers for use passes, a pure radical, aqueous emulsion polymerization process of addition be formed in a batch, semi-continuous, multistage batch, multiple stage semi-continuous or continuous executed emulsion becomes. However, the process herein uses a reaction scheme of a simultaneous starch degradation and a monomeric polymerization.

Preferably the polymerization according to the present invention as a semi-continuous Polymerization run. The semi-continuous polymerization as in the present Invention criterion consequently, generally includes a first loading a polymerization vessel with the reaction medium, such as Water (and preferably additional Components, the preparation of a stable dispersion of the prepared Polymer in the reaction medium enable). These components optionally include a surfactant, a. Strength would this time can also be added.

Also may be added other ingredients that are known in the art, such as Seed latexes for particle size regulation, Monomer precharge for which, in situ seed latex preparation, polymer initiators, polymer initiators / catalysts / accelerators Chain transfer agent and complexing the removal of randomly occurring metal that can also be added. As stated above, are iron, manganese, nickel, cerium, and copper not desirable Additives in the described process.

Among Movement, water, additives and starch then up to a temperature typically in the range of 74 ° to about 85 ° C heated. is under constant persulfate stir added. After a certain period of time (typically 1 to 30 min) begins a controlled addition of the monomer, wherein the monomer continuously over a prescribed period of time (typically 4-90 min) under constant stir is added. While this time, the starch resistant degraded and the monomer to give a stable dispersion of polymer implemented. After completion of the controlled monomer addition&lt;?page 6?&gt;becomes continuously the generated graft copolymer at a temperature and stirred held to the full to facilitate consumption of the monomers. Thereafter, the copolymer is chilled and it can additional components be added.

Optional close components defoamers a, wetting agents, thickeners, bases, ammonia, or additional Water. To rinse can the polymerization reactor of oxygen an inert gas be used, which during the entire polymerization process can be continued.

In other embodiments granted the invention provides a coating or binder. Such Coating composition includes about 10% wt to 90 °.% Of Total solids, the aforementioned strength stabilized polymer emulsion and about 10% to 90 wt.% pigment. Preferably close the Coatings about 10% to 20 wt.% Of the solids, the aforementioned starch stabilized A polymer emulsion and about 80% to 90 wt.% Pigment.

In other embodiments Alternatively, the invention can provide an ink composition, which is prepared by combining the above emulsion with a. Pigment. Such ink compositions include about 10% to 90% of the total solids weight. The aforementioned starch stabilized A polymer emulsion and about 10% to 90 wt.% Pigment. Preferred include ink compositions about 10% to 20% of the total solids weight. the aforementioned starch stabilized A polymer emulsion and about 80% to 90 wt.% Pigment.

Preferred Pigments for use in both the coatings and in the ink compositions are carbon black and organic pigments, such as Calciumlithol Red and Blue Phthalol.

The Invention is also especially suitable for application for inclusion in clearcoat coatings (overprint varnishes) Basic sprays, technical wood impregnation, adhesive applications and ink systems.

It Following are several examples of preparations of the polymeric emulsions of the present invention, and coatings and ink compositions of the present invention.

Example 1 - Emulsion Polymer

In a 2-liter four-necked round bottom flask equipped with a thermometer and a thermostat (thermal Watch^®, Instruments for Research and Industry, Cheltenham, PA), a condenser, agitator, a nitrogen purge and a heating mantle was charged 684.5 g of deionized Water and 90.3 grams of starch product, Penford gum 230 given. Under agitation until the temperature was 82 ° C increased, after which the Starch granules were solubilized and yielded a viscous solution.

Among continued movement, an aqueous solution of ammonium persulfate (APS) (7.1 g APS, 35 grams deionized water) was added. The temperature was for held for 30 minutes with continued agitation at 82 ° C. With a flush of of deionized water was 3 g Tergitol 15-S-7 as a surfactant (3.25 g) added and a mixture of ethylenically unsaturated Monomers and chain transfer agent with By a mechanical pump regularly over 90 minutes according to the following Scheme added: <img img-content="tb" img-format="tif" he="26" wi="154" file="00090001.tif" />

After End of the monomer was deionized pump with 12.75 g Water flushed (into the reactor) and an additional Batch of 0.5 g APS in 7.1 grams of deionized water added. The Reaction mixture was continuous for an additional holding period of 1 hour touched, after which the reaction mixture was cooled and an additional Batch of 28.1 g deionized water was added and by a 100 micron filter in a glass container was filtered. The resulting translucent to milky starch Pfropfemulsionspolymer was homogeneous and stable and no flocculation or a Settling observed.

&lt;?page 7?&gt;

Example 2 - Emulsion Polymer

In a 2-liter four-necked round bottom flask equipped with a thermometer and a thermostat (thermal Watch, Instruments for Research and Industry, Cheltenham, PA), a condenser, a stirrer, a nitrogen purge and a heating mantle was charged 682.3 g of deionized Water and 90.3 grams of starch product, Penford gum 230 given. Under agitation until the temperature was 82 ° C increased, after which the Starch granules were solubilized and yielded a viscous solution.

Among continued movement, an aqueous solution of ammonium persulfate (APS) (7.1 g APS, 33.7 grams deionized water) was added. The temperature was for held for 30 minutes with continued agitation at 82 ° C. With a flush of deionized water, 2.4 g Tergitol 15-S-7 as a surfactant (3.25 g) and a mixture of ethylenically unsaturated Monomers and chain transfer agent with the aid of a mechanical pump regularly over 90 min according to the following Scheme added: <img img-content="tb" img-format="tif" he="26" wi="155" file="00100001.tif" />

After End of the monomer was deionized pump with 15.7 g Water flushed (into the reactor) and an additional Batch of 0.5 g APS in 7.1 grams of deionized water added. The reaction mixture was used throughout for an additional Holding period of 1 hour, stirred, after which the reaction mixture was cooled and an additional Charge was added 12.6 grams of deionized water and a solution 0.36 g of Kathon LX-14 (a biocide made by Rohm &amp; Haas) in 6.8 g deionized water. The reaction mixture was filtered through a 100 micron filter in a glass container filtered. The resulting translucent to milky starch Pfropfemulsionspolymer was homogeneous and stable and no flocculation or a Settling observed.

Example 3 - Emulsion Polymer

In a 2-liter four-necked round bottom flask equipped with a thermometer and a thermostat (thermal Watch, Instruments for Research and Industry, Cheltenham, PA), a condenser, a stirrer, a nitrogen purge and a heating mantle was charged 694.8 g of deionized Water and 91.0 grams of starch product, Penford gum 230 given. Under agitation until the temperature was 82 ° C increased, after which the Starch granules were solubilized and yielded a viscous solution. With continued Movement, an aqueous solution of ammonium persulfate (APS) (7.2 g APS, 35.2 grams of deionized water) added. The temperature was for 30 min with continued Moving at 82 ° C retained and a mixture of ethylenically unsaturated monomers and chain transfer agent with the aid of a mechanical pump regularly over 90 min according to the following Scheme added: <img img-content="tb" img-format="tif" he="39" wi="154" file="00110001.tif" />

The Reaction mixture was continuous for an additional holding period of 1 hour touched, after which the reaction mixture was cooled and an additional Charge was added 28.1 grams of deionized water. The reaction mixture was filtered through a 100 micron filter in a glass container filtered. The resulting translucent to milky starch Pfropfemulsionspolymer was homogeneous and stable and there were no effect or dismissal to observe.

What is important, it must be recognized that the above-described Operating procedure under substantially the same conditions as the can take place above polymerization procedure. In order to&lt;?page 8?&gt;can the Degradation / copolymerization mainly be achieved simultaneously. This grants shortened overall times of the process and eliminates the necessity of undesirable Additives in the finished emulsion polymer.

Example 4 - Pigment

After the following formulation was a ground base composition produced: <img img-content="tb" img-format="tif" he="57" wi="156" file="00110002.tif" />

The Dispersion of the carbon black in water was obtained by 750 g grinding media steel balls with 12 mm in a tin a Size of 1 pint ((about 0.5 liters, the trans.)) was added, the aforementioned composition given in the bush was and the bush was closed and 16 hours on a roller mill set (US Stoneware Corp., East Palestine, OH). The resultant ground Basic vehicle was stable, uniform and liquid, without discontinuation or flocculated material.

Example 5 - Emulsion Polymer Pigment

It was the pigment prepared in Example 4 used by the following recipe to prepare a black ink: <img img-content="tb" img-format="tif" he="47" wi="155" file="00120001.tif" />

The final The composition of the black ink was prepared by the ground base vehicle in a 4 oz glass jar ((1 oz. about 31 g, the trans.)) weighed, the inlet vehicle with mechanical agitation (approximately 600 U / min) over several minutes was added, followed by addition of the deionized Water under continued movement. Mixing was so long continued until everything was homogeneous. The resulting aqueous ink was stable with respect to settling and contained no grainy material.

The Suitability of this aqueous Ink was evaluated by force coated substrates were prepared, by pouring the ink onto the Kraft (3NT-5 paper, Leneta Co., Mahwah NJ), using a laboratory-scale Tintenapplikators in Standard design (165-p "Handpoofer"). The in this way obtained by using the ink described in this example blackened surfaces were uniform and showed color strength, Color transfer and Leimungsfestigkeit, the commercial on a reference in Standard product were equivalent or better.

&lt;?page 9?&gt;

Example 6 - Paper Primer

In the following manner has been illustrated, a paper primer for porous paper surfaces. The Starch graft copolymer, which was prepared in Example 1 was applied to 40 pound Kraft paper (40 pound paper weight per 1000 in² Paper surface) is plotted, by an automatic laboratory coater was used (K-Coater, Gardner Co. Pompano Beach, FL) wherein a # 1 K-blade was used at a speed setting of "10" (Approximately 4 ft./min drawing speed). This was followed by a second coating of Joncryl^® 77 from SC Johnson Polymer (diluted with deionized water 100 cP) as the top coat, in the identical conditions of were applied. This primer / topcoat construction was with a similar compared structure of 2 layers of Joncryl^® 77 had, and was summarized in the following table: <img img-content="tb" img-format="tif" he="55" wi="155" file="00130001.tif" />

The according to the present invention produced starch Pfropfemulsionspolymere find applicability in a number of other applications for coatings and inks. It is to be understood that the above exported Examples certain illustrate preferred embodiments and do not limit the scope. Accordingly, such alternatives, modifications to consider and modifications as part of the invention, inasmuch as they belong to the spirit and scope of the appended claims:

Industrial applicability

The granted invention a starch-polymer emulsion at a low cost, which, in conjunction with graphic materials, coating compositions is and adhesive applicable. Particularly applicable is for a pigment dispersant or an ink binder component in applications in the field the graph.