KR0134501B1 - Method of polymerization of resin for controlling gloss - Google Patents

Abstract

The present invention relates to a method for producing a resin for adjusting glossiness in order to reduce the surface gloss of a thermoplastic resin such as PVC.

The present invention relates to (i) emulsion polymerization of (i) a monomer comprising an aromatic vinyl monomer, an acrylic monomer, a cyanide compound, a crosslinking agent and a graft agent or a monomer comprising an acrylic monomer, an aromatic vinyl monomer and a graft agent And (ii) a secondary emulsion polymerization of the crosslinking agent between the aromatic vinyl monomer, the acrylic monomer, the cyanide compound and the acrylamide particles, or the second emulsion polymerization of the crosslinking agent between the acrylic monomer and the acrylamide particles. Preparing a latex having a core / shell structure by grafting the core to the core, (b) agglomerating the latex and crosslinking the particles of the latex with the interparticle crosslinking agent, wherein Method of producing a resin for gloss control, characterized in that it comprises the addition of to activate the cross-linking reaction between particles To provide.

A matte thermoplastic resin can be obtained by mixing the gloss adjustment resin obtained according to the invention with a thermoplastic resin such as PVC.

Description

Manufacturing method of resin for gloss adjustment

The present invention relates to a method for producing a resin for adjusting gloss, and more particularly, to a method for producing a resin for adjusting glossiness for reducing the surface gloss of a thermoplastic resin such as PVC. The present invention also relates to a method for reducing the gloss of a thermoplastic resin by mixing the gloss adjusting resin prepared by the above method with a thermoplastic resin.

There are various methods to reduce the surface gloss of thermoplastic resins, such as processing or adding inorganic additives such as silica gel, but these methods have high manufacturing cost and adversely affect the mechanical properties of the product. Therefore, a method of adding an organic additive such as a polymer resin has been developed and used. In this method, a polymer resin having a lower thermal shrinkage than a thermoplastic resin is synthesized and processed by mixing it with a thermoplastic resin, and the molded article prepared from the polymer particles having a low thermal shrinkage due to the difference in mutual shrinkage between resins is cooled. When distributed on the surface and the particle size is enough to scatter light, the gloss of the product is reduced. Therefore, since the polymer particle size distributed on the surface of the molded article is an important factor in reducing the surface gloss of the resin, it has been focused on producing particles having a size that can exhibit a matte effect.

Currently acrylic matte resins are commercially prepared by bulk polymerization, but this method is complicated in the manufacturing process, the cost is naturally expensive and its use is limited.

Therefore, the present inventors have studied to solve the above problems, the coagulation process after forming a core / shell structure grafted to the cross-linked core part by the emulsion polymerization method completely different from the conventional bulk polymerization method The cross-linked core parts in the reaction reacted with each other again to greatly control the particle size, and it was found that the gloss could be controlled by applying it to PVC and related products, thereby completing the present invention.

That is, the present invention provides a core / shell structure by a two-step emulsion polymerization method comprising a step of preparing a core having a crosslinked structure and a step of grafting a shell to the core to reduce thermal shrinkage of the matrix resin, that is, a thermoplastic resin. It provides a latex having a, and provides a method for producing a gloss control resin comprising crosslinking the particles of the latex in the aggregation process to form a high molecular weight gel having a very large particle size (1μ or more).

The present invention also relates to a method for producing an acrylic matt thermoplastic resin by mixing such a thermoplastic resin and a resin for adjusting gloss.

The manufacturing method of the resin for adjusting glossiness of the present invention will be described in detail as follows.

First, as a first step of preparing the core, a monomer including an aromatic vinyl monomer, an acrylic monomer, a cyanide compound, a crosslinking agent and a graft agent or a monomer including an acrylic monomer, an aromatic vinyl monomer and a graft agent is added to the reactor. Emulsion polymerization proceeds. At this time, the reaction is carried out for 2 to 12 hours at a temperature of 50 to 90 ℃.

Aromatic vinyl monomers include styrene, monochloro styrene, methyl styrene, and dimethyl styrene, and acrylic monomers include methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, 2 -Acrylates such as ethyl hexyl acrylate, and methacrylates such as methyl methacrylate, ethyl methacrylate and n-butyl methacrylate, and dimers may be used alone or in combination of two or more. Can also be used.

Acrylonitrile, methacrylonitrile, etc. can be used as a cyanide compound.

As crosslinking agent, divinylbenzene, alkane polyol, polyacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, butylene glycol diacrylate, hexanediol diacrylate, hexanediol dimethacrylate, trimethylol Propanetriacrylate and the like can be used.

As the graft agent, aryl acrylate, aryl methacrylate, diaryl maleate, diaryl fumarate and the like can be used.

In the core manufacturing step, the content of the aromatic vinyl monomer is 70% by weight or less, the content of the acrylic monomer is 25 to 80% by weight, the content of the cyanide compound is 5 to 50% by weight, and the grafting agent and the crosslinking agent are each 100 reaction components. It is preferable that they are 0.05-5 weight part and 5 weight part or less per weight part.

In the emulsion polymerization reaction, in addition to the above components, it is also possible to use a reaction initiator, an emulsifier for assisting dispersion in the medium, and a molecular weight regulator.

As an initiator, a persulfate-based water-soluble initiator such as potassium persulfate and ammonium persulfate is mainly used, but an initiator generally used in emulsion polymerization such as an oil-soluble initiator and an oxidizing agent may be used, and the amount of the initiator is 100% of the total reactive content. Suitable is 0.05 to 3 parts by weight per weight part.

Examples of the emulsifier include anionic surfactants such as alkyl aryl sulfonates such as sodium dodecyl benzene sulfonate, potassium dodecyl benzene sulfonate and sodium alkyl benzene sulfonate, sodium dodecyl sulfonate and potassium dodecyl sulfonate. Sulfates such as alkyl sulfonate, sodium dodecyl sulfate, sodium octyl sulfate, sodium octadecyl sulfate, rosiate emulsifiers such as potassium rosinate and sodium rosinate or fatty acid emulsifiers such as potassium oleate and potassium stearate Its amount is preferably 0.1 to 5 parts by weight per 100 parts by weight of the total reaction components.

Molecular weight regulators include mercaptans such as t-dodecyl mercaptan and n-dodecyl mercaptan or terpenes such as dipentene and t-terpene or halogenated hydrocarbons such as chloroform and carbon tetrachloride. 6 parts by weight or less per 100 parts by weight is suitable.

Next, as a second step, the core latex prepared in the first step is subjected to graft polymerization in the same reactor. In the graft polymerization step, a crosslinking agent between the monomers and acrylamide-based particles used in the core manufacturing step is added. That is, when the crosslinking agent between the monomers and the acrylamide-based particles used in the core manufacturing step is added to the reactor containing the core latex, a shell is formed by emulsion polymerization of the components, and the shell is grafted onto the core latex. Polymerized.

As the acrylamide-based interparticle crosslinking agent, various derivatives of N-hydroxy alkyl acrylamides such as N-methylol acrylamide or N-alkyl ether acrylamides such as N-methyl ether acrylamide can be used. The above can also be mixed and used. At this time, the amount of these is suitably 0.1 to 15% by weight.

In the grafting step, the aromatic vinyl monomer is 50% by weight or less, the acrylic monomer is 30 to 90% by weight, the cyanide compound is 50% by weight or less, and the content of the emulsifier is 0.01 to 3 parts by weight per 100 parts by weight of the total reactive component. It is suitable.

The latex polymerized by the above method is agglomerated by a known method. In this process, the crosslinking reaction occurs between the latex particles and the particles by the interparticle crosslinking agent added in step 2, and the reaction is further activated in an acidic atmosphere. An acid is added to coagulate the polymerized latex. At this time, the pH of the hydrogen ion is suitably about pH 1 to 6, sulfuric acid is typically used in the present invention.

The glossiness adjusting resin thus prepared may be mixed with a thermoplastic resin, for example PVC, under ordinary conditions to reduce the gloss of the thermoplastic resin.

Matte effect of the resin produced by the present invention was observed by the following method.

3 parts by weight of dibutyltin maleate, 6 parts by weight of dioctyl phthalate, 1 part by weight of polyethylene wax, 10 parts by weight of MBS-based impact modifier (MB-830C Lucky Products) and the resin 5 of the present invention. Part by weight is dispersed in a Henschel mixer, extruded into a single screw extruder, pelletized, and a plate-shaped injection specimen is prepared by an extruder. This specimen was measured for gloss using a gloss meter (TOYO SEIKI).

Hereinafter, the following examples are described to specifically illustrate the present invention, but the present invention is not limited thereto.

Example 1

In a 1 liter flask, 200 g molar, 2 g sodium dodecyl sulfate, 0.4 g potassium persulfate and 0.5 g t-dodecyl mercaptan and 70% styrene, 30% butyl acrylate and 0.5% aryl methacrylate 100 g of the monomer was added and reacted for 10 hours while stirring at 70 ° C to prepare a core latex.

In the core latex prepared by the above method, 99 g of a monomer consisting of 10% of butyl acrylate and 90% of methyl methacrylate, 1 g of N-methylol acrylamide, 200 g of water, 0.1 g of potassium persulfate and sodium 0.5 g of dodecyl sulfate was added and reacted at 70 ° C. for 10 hours to prepare a latex having a core to shell ratio of 1: 1.

300 g of the latexes subjected to steps 1 and 2 together with 5 g of 5% sulfuric acid solution was added to 550 g of 0.5% calcium chloride aqueous solution at 60 ° C. and aged at 70 ° C. for 30 minutes. The aggregated resin was filtered and dried to obtain a powder.

The glossiness of the PVC compound was measured by the above-mentioned method using the resin obtained above, and the results are shown in Table 1.

Example 2

In a 1 liter flask, 200 g of water, 1 g of sodium dodecyl sulfate, 0.4 g of potassium persulfate and 0.5 g of t-dodecyl mercaptan with 60% by weight of styrene, 40% by weight of butyl acrylate and 0.5% by weight of aryl methacrylate 80 g of the monomer was added and reacted for 10 hours while stirring at 70 ° C to prepare a core latex.

In the core latex prepared by the above method, 19 g of a monomer consisting of 100% by weight of methyl methacrylate as a shell preparation step, 1 g of N-methylol acrylamide, 200 g of water, 0.15 g of potassium persulfate, and 2 g of sodium dodecyl sulfate were added. Addition and reaction at 70 ° C. for 10 hours yielded a latex with a core to shell ratio of 1: 1.

The latex that passed through steps 1 and 2 was aggregated in the same manner as in Example 1 to obtain a powder.

The glossiness of the PVC compound was measured by the aforementioned method using the resin obtained above, and the results are shown in Table 1.

Example 3

Except for using 35% by weight of styrene and 0.4% by weight of aryl methacrylate, and 35% by weight of acrylonitrile and 0.1% by weight of divinylbenzene were carried out in the same manner as in Example 1 the table 1 is shown.

Comparative Example 1

The test results are shown in Table 1, except that N-methylol acrylamide was not used.

Comparative Example 2

The test results are shown in Table 1 except that the acid was not mixed with the aqueous calcium chloride solution during the flocculation process.

As can be seen from Table 1, the PVC compounds of Examples 1, 2 and 3 of the present invention can be seen that the gloss is significantly lower than the PVC compounds of Comparative Examples 1 and 2.

Claims (4)

In the method for producing a gloss control resin by a core / shell structure latex consisting of a core having a crosslinked structure and a shell grafted thereto, (a) (i) an aromatic vinyl monomer, an acrylic monomer, a cyanide compound, a crosslinking agent and a graft; Emulsifying and polymerizing a monomer mixture comprising an agent or a monomer mixture including an acrylic monomer, an aromatic vinyl monomer, and a graft agent to prepare a core latex, and (ii) to the core latex obtained in step (i), to an aromatic vinyl A latex having a core / shell structure is prepared by adding a monomer mixture comprising a monomer, an acrylic monomer and a cyanide compound or an acrylic monomer together with an acrylamide-based interparticle crosslinking agent to graft emulsion polymerization to graf the shell to the core. (B) coagulation by adding acid to the core / shell structure latex And at the same time, crosslinking the particles of the latex by the interparticle crosslinking agent. The method according to claim 1, wherein the acrylamide-based interparticle crosslinking agent is N-hydroxyalkylacrylamide or N-alkyletheracrylamide derivative. The method according to claim 1, wherein 0.1 to 15% by weight of the crosslinking agent between acrylamide particles added to the shell manufacturing step is used. A method of resisting the gloss of a thermoplastic resin by mixing the gloss adjustment resin obtained by the method of claim 1 with a thermoplastic resin.