阅读说明：本技术 丙烯酸类共聚物、它的制备方法和包含它的丙烯酸类共聚物组合物 (Acrylic copolymer, method for preparing the same, and acrylic copolymer composition comprising the same ) 是由 辛相镇 韩政洙 余承旭 郑龙硕 于 2019-11-07 设计创作，主要内容包括：本发明涉及一种丙烯酸类共聚物,更具体地,提供一种丙烯酸类共聚物、该丙烯酸类共聚物的制备方法和包含所述丙烯酸类共聚物的丙烯酸类共聚物组合物,所述丙烯酸类共聚物包含：来自主单体的重复单元；和来自链转移剂的部分,其中,所述来自主单体的重复单元包含来自(甲基)丙烯酸烷基酯单体的重复单元、来自(甲基)丙烯酸烷氧基烷基酯单体的重复单元和来自交联单体的重复单元,所述来自链转移剂的部分来自具有硫代羰基硫基的链转移剂,并且相对于100重量份的所述来自主单体的重复单元,所述来自链转移剂的部分的含量为0.03重量份至0.08重量份。(The present invention relates to an acrylic copolymer, and more particularly, to an acrylic copolymer comprising: a repeating unit derived from a main monomer; and a moiety derived from a chain transfer agent, wherein the repeating unit derived from the main monomer comprises a repeating unit derived from an alkyl (meth) acrylate monomer, a repeating unit derived from an alkoxyalkyl (meth) acrylate monomer, and a repeating unit derived from a crosslinking monomer, the moiety derived from the chain transfer agent is derived from a chain transfer agent having a thiocarbonylthio group, and the moiety derived from the chain transfer agent is contained in an amount of 0.03 to 0.08 parts by weight with respect to 100 parts by weight of the repeating unit derived from the main monomer.)

1. An acrylic copolymer comprising:

a repeating unit derived from a main monomer; and

the portion from the chain transfer agent(s),

wherein the repeating units derived from the main monomer comprise repeating units derived from an alkyl (meth) acrylate monomer, repeating units derived from an alkoxyalkyl (meth) acrylate monomer, and repeating units derived from a crosslinking monomer,

the moiety derived from the chain transfer agent is derived from a chain transfer agent having a thiocarbonylthio group, and

the content of the moiety derived from the chain transfer agent is 0.03 parts by weight to 0.08 parts by weight with respect to 100 parts by weight of the repeating unit derived from the main monomer.

2. The acrylic copolymer according to claim 1, wherein the content of the moiety derived from the chain transfer agent is 0.045 to 0.07 parts by weight with respect to 100 parts by weight of the repeating unit derived from the main monomer.

3. The acrylic copolymer according to claim 1, wherein the chain transfer agent is selected from the group consisting of 4-cyano-4- (phenylthiocarbonylthio) pentanoic acid, 1,1, 1-tris [ (dodecylmercaptothiocarbonylthio) acetic acid, 2- (4-methoxyphenylthiocarbonylthio) acetic acid, 2- (phenylthiocarbonylthio) propanoic acid, 2-nitro-5- (2-propynyloxy) benzyl 4-cyano-4- (phenylthiocarbonylthio) pentanoate, 3-butenyl 2- (dodecylmercaptothiocarbonylthio) -2-methylpropionate, benzyl dithiobenzoate, cyanomethyl [3- (trimethoxysilyl) propyl ] trithiocarbonate, ethyl 2- (4-methoxyphenylthiocarbonylthio) acetate and ethyl 2- (ethyl 2-) (S) One or more of phenylthiocarbonylthio) -2-phenylacetate.

4. The acrylic copolymer of claim 1 wherein the repeating units derived from a main monomer comprise repeating units derived from an ethylenically unsaturated nitrile monomer.

5. The acrylic copolymer according to claim 1, wherein the repeating unit derived from a main monomer comprises 80 to 99.9% by weight of the repeating unit derived from an alkyl (meth) acrylate monomer and the repeating unit derived from an alkoxyalkyl (meth) acrylate monomer; and 0.1 to 20 wt% of the repeating unit derived from a crosslinking monomer.

6. The acrylic copolymer of claim 1, wherein the acrylic copolymer has a weight average molecular weight of 890,000 to 1,360,000 g/mol.

7. The acrylic copolymer of claim 1, wherein the acrylic copolymer has a mooney viscosity ML at 100 ℃₁₊₄Is 10 to 70.

8. A method for preparing an acrylic copolymer, the method comprising:

a step of preparing a main monomer mixture comprising an alkyl (meth) acrylate monomer, an alkoxyalkyl (meth) acrylate monomer, and a crosslinking monomer; and

a step of adding 0.03 to 0.08 parts by weight of a chain transfer agent with respect to 100 parts by weight of the main monomer mixture and performing polymerization,

wherein the chain transfer agent has a thiocarbonylthio group.

9. The production method according to claim 8, wherein, in the step of preparing the main monomer mixture, an ethylenically unsaturated nitrile monomer is contained.

10. An acrylic copolymer composition comprising: the acrylic copolymer according to any one of claims 1 to 7; and a filler.

Technical Field

Cross Reference to Related Applications

This application claims the benefit of priority from korean patent application No. 10-2018-.

Background

The rubber component used in vehicles is only 5% of the total weight of the vehicle, but is an important part mainly for affecting vehicle performance. The rubber component is considered to be an important component due to its properties, such as a component applied to a portion where vibration and noise are generated, and a component applied to a portion where heat resistance and oil resistance are required. In particular, for an engine of a small vehicle requiring high output, a material having excellent heat resistance and oil resistance is required.

Among various specific rubbers, the acrylic rubber is a rubber having an alkyl (meth) acrylate as a main monomer unit, and has excellent heat resistance and oil resistance. Therefore, in the vehicle-related field and the like, acrylic rubber has been widely used as a material for not only seals, hoses, pipes, or belts, but also a rubber component of an adhesive. The acrylic rubber is imparted with elasticity by crosslinking so as to be used as a rubber component, and for this purpose, crosslinking monomers each having a reactive crosslinking site are copolymerized in the acrylic rubber. In general, a crosslinked acrylic rubber in which a crosslinking monomer is copolymerized is mixed with a filler material such as carbon black or a crosslinking agent to prepare a crosslinked acrylic rubber composition. The crosslinked acrylic rubber composition is molded in a mold having a desired shape and used for various purposes.

Therefore, the crosslinked acrylic rubber used for various applications is required to have excellent roll-milling processability or molding processability in order to be molded into a molded article having a desired shape and excellent heat resistance and oil resistance. Further, in order to achieve durability suitable for the above-mentioned use, the acrylic rubber is required to have a high crosslinking density. However, due to the characteristics of the crosslinked acrylic rubber, crosslinking occurs during the preparation process, so that the uniformity of the crosslinking monomer is deteriorated, which causes deterioration in workability and durability.

Disclosure of Invention

Technical problem

In order to solve the problems mentioned in the background art, it is an object of the present invention to improve the processability and durability of an acrylic copolymer by uniform crosslinking when preparing the acrylic copolymer.

That is, an object of the present invention is to provide an acrylic copolymer composition having excellent processability and durability by including an acrylic copolymer prepared by reducing self-crosslinking of the acrylic copolymer to reduce crosslinking of a polymer and controlling a reaction rate to have uniform distribution of a crosslinking monomer.

Technical scheme

In one general aspect, there is provided an acrylic copolymer comprising: a repeating unit derived from a main monomer; and a moiety derived from a chain transfer agent, wherein the repeating unit derived from the main monomer comprises a repeating unit derived from an alkyl (meth) acrylate monomer, a repeating unit derived from an alkoxyalkyl (meth) acrylate monomer, and a repeating unit derived from a crosslinking monomer, the moiety derived from the chain transfer agent is derived from a chain transfer agent having a thiocarbonylthio group, and the moiety derived from the chain transfer agent is contained in an amount of 0.03 parts by weight to 0.08 parts by weight with respect to 100 parts by weight of the repeating unit derived from the main monomer.

In another general aspect, there is provided a method of preparing an acrylic copolymer, the method comprising: a step of preparing a main monomer mixture comprising an alkyl (meth) acrylate monomer, an alkoxyalkyl (meth) acrylate monomer, and a crosslinking monomer; and a step of adding 0.03 to 0.08 parts by weight of a chain transfer agent having a thiocarbonylthio group with respect to 100 parts by weight of the main monomer mixture and performing polymerization.

In yet another aspect, an acrylic copolymer composition comprising the acrylic copolymer and a filler is provided.

Advantageous effects

The acrylic copolymer including a chain transfer agent according to the present invention induces a chain transfer reaction and reduces self-crosslinking of a polymer to reduce crosslinking of the polymer, thereby having excellent processability. In addition, the acrylic copolymer including a chain transfer agent according to the present invention controls a polymerization reaction rate to have a uniform distribution of a crosslinking monomer, thereby having excellent durability through uniform crosslinking.

Detailed description of the preferred embodiments

The terms and words used in the specification and claims of the present invention should not be construed as conventional or dictionary meanings, but should be construed as meanings and concepts satisfying the technical idea of the present invention on the basis of the principle that the inventor can appropriately define the concept of the term to describe their own invention in the best way.

The terms "repeat unit from …" and "moiety from …" in the present invention may refer to a component or structure from a particular substance, or the substance itself. As a specific example, the term "repeat unit from …" may refer to a repeat unit formed in a polymer by a monomer added at the time of polymerization participating in a polymerization reaction. The term "moiety from …" can induce a chain transfer reaction of a polymer by a chain transfer agent added during polymerization to participate in the polymerization reaction.

The term "copolymer" in the present invention may refer to a copolymer formed by copolymerizing comonomers, and may refer to a random copolymer and a block copolymer as a specific example.

Hereinafter, the present invention will be described in more detail to help understanding the present invention.

The acrylic copolymer according to the present invention may comprise a repeating unit derived from a main monomer and a moiety derived from a chain transfer agent.

The repeating unit derived from the main monomer may include a repeating unit derived from an alkyl (meth) acrylate monomer, a repeating unit derived from an alkoxyalkyl (meth) acrylate monomer, and a repeating unit derived from a crosslinking monomer.

The repeating unit derived from the alkyl (meth) acrylate monomer is a component for controlling a glass transition temperature in the acrylic copolymer and for improving processability, heat resistance and cold resistance of a final product, and may be an alkyl (meth) acrylate monomer including an alkyl group having 1 to 8 carbon atoms. Here, the alkyl group having 1 to 8 carbon atoms may be understood to include a linear or cyclic alkyl group having 1 to 8 carbon atoms. As a specific example, the alkyl (meth) acrylate monomer may be: methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, n-pentyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, and the like. Here, the alkyl (meth) acrylate monomer may be used alone or in combination of two or more of them, and as a specific example, may be ethyl (meth) acrylate, n-butyl (meth) acrylate monomer, or the like.

The content of the repeating unit from the alkyl (meth) acrylate monomer in the repeating unit from the main monomer may be 65 to 95 wt%, 75 to 93 wt%, or 80 to 90 wt%, and within the range, the processability, heat resistance, and cold resistance of the acrylic copolymer according to the present invention may be excellent.

The repeating unit derived from the alkoxyalkyl (meth) acrylate monomer is a component for controlling a glass transition temperature in the acrylic copolymer and for improving processability, heat resistance, and cold resistance of a final product, and may refer to an alkyl (meth) acrylate monomer including an alkoxyalkyl group having 1 to 8 carbon atoms. As a specific example, the alkoxyalkyl (meth) acrylate monomer may be: methoxymethyl (meth) acrylate, ethoxymethyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-propoxyethyl (meth) acrylate, 3-methoxypropyl (meth) acrylate, 4-methoxybutyl (meth) acrylate, and the like. As a specific example, the alkoxyalkyl (meth) acrylate monomer may be 2-methoxyethyl (meth) acrylate.

The content of the repeating unit from the alkoxyalkyl (meth) acrylate monomer in the repeating unit from the main monomer may be 5 to 35 wt%, 7 to 25 wt%, or 10 to 20 wt%, and within the range, the processability and oil resistance of the acrylic copolymer according to the present invention may be excellent.

Meanwhile, the total content of the repeating unit from the alkyl (meth) acrylate monomer and the repeating unit from the alkoxyalkyl (meth) acrylate monomer in the repeating unit from the main monomer may be 80 wt% to 99.9 wt%, 85 wt% to 99.9 wt%, or 90 wt% to 99.5 wt%, and within the range, the processability, heat resistance, and cold resistance of the acrylic copolymer according to the present invention may be excellent.

The repeating unit derived from the crosslinking monomer is a component providing a crosslinking functional group in the acrylic copolymer, and may be one or more selected from the group consisting of a butenedioic acid monoester monomer, an epoxy-containing monomer, and a halogen-containing monomer.

The butenedioic acid monoester monomer may be a maleic acid monoester monomer or a fumaric acid monoester monomer obtained by reacting a carboxyl group of butenedioic acid, i.e., maleic acid or fumaric acid, with an alcohol. The maleic acid monoester monomer may be: monoalkyl maleate monomers such as monomethyl maleate, monoethyl maleate, monopropyl maleate, monobutyl maleate, monopentyl maleate or monodecyl maleate; monocyclic alkyl maleate monomers such as monocyclopentyl maleate, monocyclohexyl maleate, monocyclopentyl maleate, monocycloheptyl maleate, monocyclooctyl maleate, monomethylcyclohexyl maleate, mono-3, 5-dimethylcyclohexyl maleate, monocyclopentyl maleate, or monoisobornyl maleate; a monocyclopentadienyl maleate monomer, such as monocyclopentadienyl maleate, monocyclohexenyl maleate, monocyclopentadienyl maleate or dicyclopentadienyl maleate; and so on. The fumaric acid monoester monomer may be: monoalkyl fumarate monomers such as monomethyl fumarate, monoethyl fumarate, monopropyl fumarate, monobutyl fumarate, monohexyl fumarate, or monooctyl fumarate; a monocyclic alkyl fumarate monomer such as monocyclopentyl fumarate, monocyclohexyl fumarate, monocyclopentyl fumarate, monocyclooctyl fumarate, monomethylcyclohexyl fumarate, mono-3, 5-dimethylcyclohexyl fumarate, dicyclopentyl fumarate, or isobornyl fumarate; a monocyclopentadienyl fumarate monomer, such as monocyclopentadienyl fumarate, monocyclohexenyl fumarate, monocyclopentadienyl fumarate, or monocyclopentadienyl fumarate; and so on.

The epoxy group-containing monomer may be glycidyl (meth) acrylate, vinyl glycidyl ether, allyl glycidyl ether, methacryl glycidyl ether (methacryl glycidyl ether), or the like. As a specific example, the epoxy group-containing monomer may be glycidyl (meth) acrylate, allyl glycidyl ether, or the like.

The halogen-containing monomer may be vinyl chloroacetate, vinyl bromoacetate, allyl chloroacetate, vinyl chloropropionate, vinyl chlorobutyrate, vinyl bromobutyrate, 2-chloroethyl acrylate, 3-chloropropyl acrylate, 4-chlorobutyl acrylate, 2-chloroethyl methacrylate, 2-bromoethyl acrylate, 2-iodoethyl acrylate, 2-chloroethyl vinyl ether, chloromethyl vinyl ether, 4-chloro-2-butenyl acrylate, vinylbenzyl chloride, 5-chloromethyl-2-norbornene, 5-chloroacetoxymethyl-2-norbornene, etc. As a specific example, the halogen-containing monomer may be vinyl chloroacetate, vinylbenzyl chloride, 2-chloroethyl acrylate, 2-chloroethyl vinyl ether, or the like.

The content of the repeating unit derived from the crosslinking monomer in the repeating unit derived from the main monomer may be 0.1 to 20% by weight, 0.1 to 15% by weight, or 0.5 to 10% by weight, and within the range, the acrylic copolymer according to the present invention may have a high crosslinking density and excellent mechanical characteristics, may improve the elongation of the resulting crosslinked product, and may prevent compression set.

The repeating unit derived from the main monomer may further include another repeating unit derived from a monomer copolymerizable with the repeating unit derived from the alkyl (meth) acrylate monomer and the repeating unit derived from the alkoxyalkyl (meth) acrylate monomer, in addition to the repeating unit derived from the alkyl (meth) acrylate monomer, the repeating unit derived from the alkoxyalkyl (meth) acrylate monomer, and the repeating unit derived from the crosslinking monomer.

The copolymerizable further repeat unit from the monomer may be a repeat unit from an ethylenically unsaturated nitrile monomer.

The repeating unit derived from the ethylenically unsaturated nitrile monomer is a component for further improving heat resistance, and may be acrylonitrile, methacrylonitrile, 2-chloroacrylonitrile, 2-butenenitrile, or the like. As a specific example, the ethylenically unsaturated nitrile monomer may be acrylonitrile.

In the case where the repeating unit derived from the main monomer comprises a repeating unit derived from an ethylenically unsaturated nitrile monomer, the content of the repeating unit derived from an ethylenically unsaturated nitrile monomer in the repeating unit derived from the main monomer may be 0% by weight to 20% by weight, 0.01% by weight to 10% by weight, or 0.1% by weight to 10% by weight, within which range the heat resistance of the acrylic copolymer according to the present invention may be excellent.

The moiety from the chain transfer agent is a component that causes a chain transfer reaction of the polymer, reduces self-crosslinking of the polymer, and controls the reaction rate, and may be derived from a chain transfer agent having a thiocarbonylthio group. As a specific example, the chain transfer agent may be: 4-cyano-4- (phenylthiocarbonylthio) pentanoic acid, 1,1, 1-tris [ (dodecylthiocarbonylthio) acetic acid, 2- (4-methoxyphenylthiocarbonylthio) acetic acid, 2- (phenylthiocarbonylthio) propionic acid, 2-nitro-5- (2-propynyloxy) benzyl 4-cyano-4- (phenylthiocarbonylthio) pentanoate, 3-butenyl 2- (dodecylmercaptothiocarbonylthio) -2-methylpropionate, benzyl dithiobenzoate, cyanomethyl [3- (trimethoxysilyl) propyl ] trithiocarbonate, ethyl 2- (4-methoxyphenylthiocarbonylthio) acetate, ethyl 2- (phenylthiocarbonylthio) -2-phenylacetate and phthalimidomethylbutyl Trithiocarbonates, or derivatives thereof. As a more specific example, the chain transfer agent may be 4-cyano-4- (phenylthiocarbonylthio) pentanoic acid.

The moiety from the chain transfer agent controls a reaction rate during a polymerization reaction of the acrylic copolymer, so that the chain transfer agent forming the moiety from the chain transfer agent and the radical generating initiator react with each other and are converted to a chain transfer initiator at the start of the polymerization reaction, thereby adjusting a weight average molecular weight and a branching degree of the acrylic copolymer. Such a moiety derived from a chain transfer agent may be formed at the terminal of the acrylic copolymer as a chain transfer initiator by reacting with a main monomer forming a repeating unit derived from the main monomer.

The content of the moiety derived from the chain transfer agent may be 0.03 to 0.08, 0.03 to 0.075, or 0.045 to 0.07 parts by weight relative to 100 parts by weight of the repeating unit derived from the main monomer, and within the range, the progress of the polymerization reaction of the acrylic copolymer according to the present invention may be effectively controlled, thereby improving the processability of the resulting acrylic rubber while achieving excellent physical properties. Meanwhile, when the amount of the chain transfer agent is too small, the above-mentioned effects cannot be obtained. On the other hand, when the amount of the chain transfer agent used is too large, the polymerization reaction is greatly suppressed, and thus, the productivity tends to be lowered.

The weight average molecular weight of the acrylic copolymer may be 750,000g/mol to 1,600,000g/mol, 750,000g/mol to 1,500,000g/mol, or 890,000g/mol to 1,360,000g/mol, and within the range, a reduction in preparation time and excellent mechanical properties of the acrylic copolymer may be achieved.

Mooney viscosity (ML) of the acrylic copolymer₁₊₄100 ℃) may be 10 to 70, 20 to 60, or 30 to 50, and within the range, the workability may be excellent.

Meanwhile, the mooney viscosity of the acrylic copolymer may be adjusted by adjusting a content ratio of the initiator to the chain transfer agent, the weight ratio of the initiator to the chain transfer agent may be 1:3 to 18, 1:3 to 15, or 1:4.5 to 7, and within the range, the processability may be excellent.

The method for preparing the acrylic copolymer according to the present invention comprises: a step of preparing a main monomer mixture comprising an alkyl (meth) acrylate monomer, an alkoxyalkyl (meth) acrylate monomer, and a crosslinking monomer; and a step of adding 0.03 to 0.08 parts by weight of a chain transfer agent with respect to 100 parts by weight of the main monomer mixture and performing polymerization. The chain transfer agent may have a thiocarbonylthio group.

The step of preparing the main monomer mixture may be a step for preparing a main chain of the acrylic copolymer. In the step of preparing the main monomer mixture, the type and content of the monomer added for forming the main monomer mixture may be the same as those of the monomer for forming the repeating unit derived from the main monomer described above.

In addition, the step of adding a chain transfer agent and performing polymerization may be a step for initiating a chain transfer reaction of the polymer in the acrylic copolymer. In the step of adding a chain transfer agent and performing polymerization, the type and content of the added chain transfer agent may be the same as those of the chain transfer agent from the chain transfer agent portion included in the acrylic copolymer described above.

The acrylic copolymer may be polymerized by a method such as emulsion polymerization, bulk polymerization, suspension polymerization, or solution polymerization method, and may be polymerized by an emulsion polymerization method such as a batch method, a semi-batch method, and a continuous method, by additionally using additives such as an initiator, an emulsifier, a polymerization terminator, ion-exchanged water, a molecular weight regulator, an activator, and a redox catalyst.

As an example, the initiator may be: inorganic peroxides such as sodium persulfate, potassium persulfate, ammonium persulfate, potassium perphosphate, or hydrogen peroxide; organic peroxides, such as dicumyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, p-menthane hydroperoxide, di-t-butyl peroxide, t-butyl cumyl peroxide, acetyl peroxide, isobutyl peroxide, octanoyl peroxide, benzoyl peroxide, 3,5, 5-trimethylhexanol peroxide, or t-butyl peroxyisobutyrate; and nitrogen compounds such as azobisisobutyronitrile, azobis-2, 4-dimethylvaleronitrile, azobiscyclohexanecarbonitrile, or methyl azobisisobutyrate. These polymerization initiators may be used alone or in combination of two or more of them. The initiator may be used in an amount of 0.005 to 0.2 parts by weight, relative to 100 parts by weight of the main monomer mixture.

Meanwhile, an organic peroxide or inorganic peroxide initiator may be used as a redox-type polymerization initiator by combining with a reducing agent. The reducing agent is not particularly limited, but may be a compound containing a metal ion in a reduced state, such as ferrous sulfate and cuprous naphthenate; sulfonic acid compounds such as sodium methanesulfonate; amine compounds, such as dimethylaniline; and so on. These reducing agents may be used alone or in combination of two or more of them. The reducing agent may be used in an amount of 0.03 to 20 parts by weight, relative to 1 part by weight of the peroxide.

The emulsifier may be one or more selected from the group consisting of an anionic emulsifier, a cationic emulsifier and a nonionic emulsifier. Specific examples of the emulsifier may include: nonionic emulsifiers such as polyoxyethylene alkyl ethers, polyoxyethylene alkylphenol ethers, polyoxyethylene alkyl esters, or polyoxyethylene sorbitan alkyl esters; anionic emulsifiers, for example salts of fatty acids, such as myristic acid, palmitic acid, oleic acid, or linolenic acid, alkylbenzenesulfonates, such as sodium dodecylbenzenesulfonate, higher alcohol phosphates, or alkylsulfosuccinates; cationic emulsifiers, such as alkyltrimethylammonium chloride, dialkylammonium chloride, or benzylammonium chloride; copolymerizable emulsifiers such as sulfonic acid esters of α, β -unsaturated carboxylic acids, sulfuric acid esters of α, β -unsaturated carboxylic acids, or sulfonic alkyl aryl ethers; and so on. Among them, anionic emulsifiers are preferably used. The emulsifier may be used in an amount of 0.1 to 10 parts by weight, relative to 100 parts by weight of the main monomer mixture.

Water may be used as the ion-exchanged water. The ion exchange water may be used in an amount of 100 parts by weight to 400 parts by weight with respect to 100 parts by weight of the main monomer mixture.

Examples of the molecular weight regulator may include: mercaptans such as alpha-methylstyrene dimer, tert-dodecyl mercaptan, n-dodecyl mercaptan and octyl mercaptan; halogenated hydrocarbons such as carbon tetrachloride, methylene chloride and methylene bromide; and sulfur-containing compounds such as tetraethylthiuram disulfide, dipentamethylenethiuram disulfide, diisopropylxanthogen disulfide, and the like. The molecular weight regulator may be used in an amount of 0.1 to 3 parts by weight, relative to 100 parts by weight of the main monomer mixture.

As an example, the activator may be one or more selected from sodium bisulfite (sodium hydrosulfite), sodium formaldehyde sulfoxylate, sodium edetate, ferrous sulfate, lactose, glucose, sodium linolenate, and sodium sulfate. The activator may be used in an amount of 0.01 to 0.15 parts by weight, relative to 100 parts by weight of the main monomer mixture.

Examples of the redox catalyst may include sodium formaldehyde sulfoxylate, ferrous sulfate, disodium ethylenediaminetetraacetate, and copper sulfate. The redox catalyst may be used in an amount of 0.01 to 0.1 parts by weight, relative to 100 parts by weight of the main monomer mixture.

The acrylic copolymer composition according to the present invention may comprise the acrylic copolymer obtained as described above and a filler.

The filler may be carbon black, silica, kaolin, talc, diatomaceous earth, and the like.

The content of the filler may be 20 to 80 parts by weight, 30 to 65 parts by weight, or 45 to 55 parts by weight with respect to 100 parts by weight of the acrylic copolymer, within which the processability and mechanical properties may be excellent.

Meanwhile, the acrylic copolymer composition according to the present invention may further include sulfur in order to improve the hybrid crosslinking effect.

In addition, the acrylic copolymer composition may optionally further comprise a crosslinking agent and a crosslinking accelerator. As the crosslinking agent, an amine compound may be used, and as a specific example, a polyvalent amine compound may be used.

Specific examples of the polyvalent amine compound may include: aliphatic polyvalent amine crosslinking agents and aromatic polyvalent amine crosslinking agents.

Examples of the aliphatic polyvalent amine crosslinking agent may include: hexamethylenediamine, hexamethylenediamine carbamate and N, N' -di-cinnamylidene-1, 6-hexamethylenediamine.

Examples of the aromatic polyvalent amine crosslinking agent may include: 4,4 '-methylenedianiline, m-phenylenediamine, 4' -diaminodiphenyl ether, 3,4 '-diaminodiphenyl ether, 4' - (m-phenylenediisopropylidene) diphenylamine, 4'- (p-phenylenediisopropylidene) diphenylamine, 2' -bis [4- (4-aminophenoxy) phenyl ] propane, 4 '-diaminobenzanilide, 4' -bis (4-aminophenoxy) biphenyl, m-xylylenediamine, p-xylylenediamine, 1,3, 5-benzenetriamine and 1,3, 5-triaminomethylbenzene.

The content of the crosslinking agent may be 0.05 to 20 parts by weight, 0.1 to 10 parts by weight, or 0.3 to 6 parts by weight with respect to 100 parts by weight of the acrylic copolymer, within which the shape of the crosslinked product can be easily maintained and the elasticity can be excellent.

The crosslinking accelerator may be used in combination with the polyvalent amine crosslinking agent. The crosslinking facilitator can have a base dissociation constant in water at 25 ℃ of 10 to 106 or 12 to 106. Specific examples of the crosslinking accelerator may include: guanidine compounds, imidazole compounds, quaternary onium salts, tertiary phosphine compounds, and alkali metal salts of weak acids. Examples of the guanidine compound may include 1, 3-diphenylguanidine and di-o-tolylguanidine. Examples of the imidazole compound may include 2-methylimidazole and 2-phenylimidazole. Examples of the quaternary onium salt may include tetra-n-butylammonium bromide and octadecyl-tri-n-butylammonium bromide.

Examples of the polyvalent tertiary amine compound may include triethylenediamine and 1, 8-diazabicyclo [5.4.0] undecene-7. Examples of the tertiary phosphine compound may include triphenylphosphine and tri (p-tolyl) phosphine. Examples of the alkali metal salt of the weak acid may include sodium or potassium phosphate, inorganic weak acid salts such as carbonate, or organic weak acid salts such as stearate or laurate.

The content of the crosslinking accelerator may be 0.1 to 20 parts by weight, 0.2 to 15 parts by weight, or 0.3 to 10 parts by weight with respect to 100 parts by weight of the acrylic copolymer, within which the crosslinking rate may be sufficiently maintained and the tensile strength of the crosslinked product may be excellent.

The acrylic copolymer composition according to the present invention may further comprise additives such as reinforcing agents, anti-aging agents, light stabilizers, plasticizers, lubricants, adhesives, flame retardants, antifungal agents, antistatic agents and colorants, as required.

The mixing of the acrylic copolymer composition according to the present invention may be performed by a suitable mixing method such as a roll mixing, a banbury mixing, a screw mixing, or a solution mixing method, and as a specific example, may be performed by a roll mixing method. The mixing order is not particularly limited, but it is preferable to sufficiently mix components which are difficult to react or decompose by heating, and then mix components which are easily reacted or decomposed by heating, such as a crosslinking agent, at a temperature at which the reaction or decomposition does not occur within a short time. The acrylic copolymer composition according to the present invention has a small degree of rubber adhesion to a roll and has excellent processability when roll mixing grinding is performed with a roll.

In addition, the molding method of the acrylic copolymer composition according to the present invention may be performed by compression molding, injection molding, transfer molding, or extrusion molding. Further, the crosslinking method is preferably selected according to the shape of the crosslinked product, and may be a method of simultaneously performing molding and crosslinking, a method of performing crosslinking after molding, or the like. The acrylic copolymer composition according to the present invention is obtained by using the acrylic copolymer having the above-described structure, so that the acrylic copolymer is excellent in fluidity at the time of molding, and the degree of occurrence of burrs at the time of molding is low, and the molding accuracy of the obtained molded article is high.

The acrylic copolymer composition according to the present invention can be prepared into a crosslinked product by heating. After the acrylic copolymer of the present invention is crosslinked, a product may be manufactured by forming the acrylic copolymer into a desired shape through a molding or extrusion process and simultaneously or subsequently curing the acrylic copolymer.

In addition, the manufactured product may be used as various vehicle parts such as rubber for mounting an engine, a transmission seal, and a crankshaft seal.

Hereinafter, the present invention will be described in more detail by examples. However, the following examples are provided to illustrate the present invention. It will be apparent to those skilled in the art that various modifications and changes may be made without departing from the scope and spirit of the invention, and the scope of the invention is not limited thereto.