KR20110035018A - Acryl-based resin composition with high impact resistance - Google Patents

Abstract

PURPOSE: An acryl-based resin composition is provided to ensure excellent transparency and heat resistance while maintaining shock resistance, and to enable use as optical or display materials. CONSTITUTION: An acryl-based resin composition comprises an acryl-based resin and an acryl-based impact reinforcing agent. The acryl-based resin comprises a copolymer including alkyl(meth)acrylate, ring-type (meth)acrylate, acid anhydride-based monomer or derivatives thereof. The acryl-based impact reinforcing agent includes seeds containing a polymer of a monomer having alkyl methacrylate; an acryl-based rubber core containing a copolymer of a monomer having alkyl acrylate and vinyl aromatic compounds; and a shell containing a copolymer of a monomer having alkyl methacrylate and ring-type (meth)acrylate.

Description

Impact-resistant acrylic resin composition {ACRYL-BASED RESIN COMPOSITION WITH HIGH IMPACT RESISTANCE}

The present invention relates to an impact resistant acrylic resin composition having excellent transparency while maintaining impact resistance using an acrylic impact modifier having a core-shell structure, and having improved heat resistance, suitable for use in optical or display materials.

Core-shell structured impact modifiers have been used to reinforce the impact resistance, chemical resistance, processability and weather resistance of thermoplastics. Methyl methacrylate-butadiene-styrene (MBS) resins, acrylic resins, ethylene chloride (CPE) resins, silicone resins and the like are used depending on the application.

The use of such impact modifiers was mostly limited to impact reinforcement of polyvinyl chloride, but gradually, engineering plastics such as polyalkylene terephthalate resin, polyamide resin, polyacetal resin, polycarbonate resin, and two or more alloys thereof The area of use is widening with resin.

On the other hand, acrylic resins such as PMMA are polymers formed by polymerizing acrylate monomers or methacrylate monomers and polymerizing only acrylate monomers or methacrylate monomers alone or bulk polymerization, suspension polymerization, or solution of other monomers. It is resin manufactured by copolymerization by superposition | polymerization etc ..

However, acrylic resins prepared in this way have a weaker impact strength than other plastic materials, so they have the drawback of being easily broken by external impacts.

Therefore, technologies on impact resistance reinforcement using impact modifiers have been continuously studied.

The present invention is to solve the problems of the prior art as described above, an object of the present invention is to provide an impact-resistant acrylic resin composition excellent in transparency and improved heat resistance while maintaining the impact resistance.

One aspect of the present invention for achieving the above object is an acrylic resin (A) comprising a copolymer of alkyl (meth) acrylate, cyclic (meth) acrylate and monomers including acid anhydride monomers or derivatives thereof. ; And a seed (a) comprising a polymer of a monomer comprising an alkyl methacrylate, an acrylic rubber core (b) surrounding the seed and comprising a copolymer of a monomer comprising an alkyl acrylate and an aromatic vinyl compound, and It provides an acrylic resin composition comprising an acrylic impact modifier (B) surrounding the core and comprising a shell (c) comprising a copolymer of a monomer comprising an alkyl methacrylate and a cyclic (meth) acrylate.

Acrylic resin according to the manufacturing method of the present invention is excellent in transparency while maintaining the impact resistance, heat resistance is improved is suitable for use in optical or display materials.

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

One aspect of the present invention, an acrylic resin (A) comprising a copolymer of a monomer comprising an alkyl (meth) acrylate, a cyclic (meth) acrylate and an acid anhydride monomer or a derivative thereof; And an acrylic rubber core (b) comprising a seed (a) comprising a polymer comprising alkyl methacrylate, a copolymer surrounding the seed and comprising a copolymer of an alkyl acrylate and a monomer comprising an aromatic vinyl compound, and the core An acrylic resin composition comprising an acrylic impact modifier (B) wrapped and comprising a shell (c) comprising a copolymer of a monomer comprising an alkyl methacrylate and a cyclic (meth) acrylate.

Here, the term "(meth) acrylate" refers to acrylate and methacrylate collectively. In addition, an "acrylic resin" is a polymer formed by polymerizing an acrylate monomer or a methacrylate monomer and polymerizing only an acrylate monomer or a methacrylate monomer alone or together with other comonomers, bulk polymerization, suspension polymerization, and solution. It means resin produced by copolymerization by polymerization or the like.

In the acrylic resin composition, the alkyl group of the alkyl (meth) acrylate is more preferably 1 to 5 carbon atoms. Specific examples of the alkyl (meth) acrylate include methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, Butyl acrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, isobutyl methacrylate, and the like, but are not limited thereto.

In the acrylic resin composition, the cyclic (meth) acrylate is a C6-C12 cycloalkyl group, a C6-C12 aryl group, and a C6-C12 that is unsubstituted or substituted with an alkyl group having 1 to 5 carbon atoms. It is preferable that it is (meth) acrylate substituted with the group chosen from the group which consists of a C1-C3 alkyl group substituted by the aryl group or the aryloxy group. Specific examples of the cyclic (meth) acrylate include cyclohexyl methacrylate, benzyl methacrylate, cyclohexyl acrylate, 2-phenoxyethyl acrylate, 3,3,5-trimethylcyclohexyl methacrylate, phenyl Methacrylate, naphthyl methacrylate, and the like, but is not limited thereto.

In the acrylic resin composition, the acid anhydride monomer or a derivative thereof may include a monovalent or divalent or higher polyhydric carboxylic acid anhydride, anhydride represented by the following formula (1) or an imide derivative thereof.

[Formula 1]

In the above formula, R ₁ and R ₂ are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms.

The imide derivative includes N-substituted maleimides such as N-methyl maleimide, N-ethyl maleimide, N-butyl maleimide, N-cyclohexyl maleimide, and more preferably N-phenyl maleimide. .

The acrylic resin (A) preferably contains 60 to 90% by weight of alkyl (meth) acrylate, more than 0 to less than 30% by weight of cyclic (meth) acrylate, and 1 to 20% by weight of an acid anhydride monomer or derivative thereof. Do.

In the present invention, it is preferable to use an acrylic impact modifier (B) as the impact modifier of acrylic resin (A). The acrylic impact modifier (B) is an acrylic rubber comprising a copolymer (a) comprising a polymer of a monomer containing an alkyl methacrylate, the seed wrap, and a monomer comprising an alkyl acrylate and an aromatic vinyl compound. A core (b) and a shell (c) surrounding the core and comprising a copolymer of an alkyl methacrylate and a monomer comprising the cyclic (meth) acrylate.

In the acrylic resin composition, the weight ratio of acrylic resin (A) and acrylic impact modifier (B) is preferably 70:30 to 90:10. When the weight ratio of the acrylic resin (A) and the acrylic impact modifier (B) is within the above range, the impact resistance may be maintained while the heat resistance may be improved.

When explaining the acrylic impact modifier (B) of the present invention in detail.

The seed (a) included in the acrylic impact modifier (B) of the present invention is formed of a polymer of a monomer containing an alkyl methacrylate, wherein an emulsifier, an initiator, a crosslinking agent, and ion-exchanged water used in the emulsion polymerization may be used. Can be used.

The alkyl of the alkyl methacrylate of the seed (a) is preferably alkyl having 1 to 5 carbon atoms, more preferably methyl.

The seed (a) preferably has an average particle diameter of 50 to 200 nm.

The seed (a) is preferably included 1 to 30% by weight based on the total amount of the acrylic impact modifier (B). When the content of the seed (a) is in the above range, the processing is easy and the impact strength of the resin composition can be maintained.

The acrylic rubber core (b) included in the acrylic impact modifier (B) of the present invention may surround the seed (a) and be formed of a copolymer of a monomer including an alkyl acrylate and an aromatic vinyl compound.

The core may be formed by polymerizing 8 to 50% by weight of alkyl acrylate and 2 to 20% by weight of aromatic vinyl compound with respect to 100% by weight of the total monomers forming the acrylic impact modifier (B).

The alkyl acrylate may be preferably an acrylate substituted with an alkyl group having 1 to 5 carbon atoms, and specific examples thereof include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, and butyl acrylate. One or more selected from may be used, but is not limited thereto.

In addition, specific examples of the aromatic vinyl compound include styrene, alphamethyl styrene, paramethyl styrene, and vinyl toluene. Etc., but is not limited thereto.

The acrylic rubber core (b) is preferably contained 10 to 70% by weight based on the total amount of the acrylic impact modifier (B). When the content of the acrylic rubber core (b) is in the above range, it is possible to maintain the impact strength and hardness of the resin composition.

The shell (c) included in the acrylic impact modifier (B) of the present invention may surround the core and be formed of a copolymer of a monomer including an alkyl methacrylate and the cyclic (meth) acrylate.

That is, it is preferable to use the same cyclic (meth) acrylate as that used for the acrylic resin (A) as the component of the shell (c), in which case the compatibility with the acrylic resin (A) is increased to increase the acrylic resin. The transparency of the can be easily adjusted.

In addition, the copolymer forming the shell (c) may further include an aromatic vinyl compound as a comonomer. The aromatic vinyl compound may use the same components as the aromatic vinyl compound used in the acrylic rubber core (b).

The copolymer forming the shell is based on 100% by weight of the total monomer constituting the acrylic impact modifier (B). 6 to 60% by weight of alkyl methacrylate, 2 to 10% by weight of cyclic (meth) acrylate, and 2 to 20% by weight of aromatic vinyl compound. The alkyl methacrylate-cyclic (meth) acrylate-aromatic vinyl compound forming the shell may be included in a weight ratio of 6 to 60: 2 to 10: 2 to 20.

The shell (c) is preferably contained 10 to 80% by weight based on the total amount of the acrylic impact modifier (B). When the content of the shell (c) is in the above range, the shell can surround the acrylic rubber core (b) sufficiently, and the impact strength can be maintained.

The acrylic impact modifier (B) is preferably an average particle diameter of 200nm to 1000nm, when there is an effect excellent in workability.

In the acrylic impact modifier (B) according to the present invention, the refractive indexes of the seeds (a), the core (b), and the shell (c) are preferably 1.49 to 1.51, respectively. It is advantageous to maintain transparency when the refractive indices of each of the seeds (a), core (b) and shell (c) are within this range. It is more preferable that the refractive indices of each of the seed (a), the core (b) and the shell (c) are equal to each other within the above range.

0.01 to 0.5 parts by weight of the thermal stabilizer may be further included with respect to 100 parts by weight of the acrylic resin composition including the acrylic resin (A) and the acrylic impact modifier (B). The heat stabilizer may be used without limitation, a heat stabilizer commonly used in the art.

The acrylic resin composition according to the present invention is excellent in transparency while maintaining impact resistance using an acrylic impact modifier of a core-shell structure, and improves heat resistance. The acrylic resin composition according to the present invention preferably has a heat resistance of 115 ° C or higher, a transmittance of 90 or higher, a haze of 1.5 or lower, and an impact resistance of 3.5 or higher.

Therefore, the acrylic resin composition according to the present invention is suitable for use in optical or display materials, and specifically, may be used in coating compositions for TVs, computer monitors, notebook computers, mobile phone screens, or films for display screens. In addition, the acrylic resin composition according to the present invention can be used for optical or display devices. However, the scope of the present invention is not limited only to the above examples, and may be used without limitation as long as the application requires excellent impact resistance, heat resistance or transparency.

Hereinafter, preferred examples will be described to aid in understanding the present invention. The following examples are merely to illustrate the invention, but are not intended to limit the scope of the invention.

The physical property evaluation method in this invention is as follows.

Glass transition temperature (Tg) was measured using a DSC (Differential Scanning Calorimeter) of TA Instrument. Total transmittance (Tt) and haze (Tt) and haze were measured by measuring the total light transmittance (Tt) and haze of 3 mm thick specimens according to ASTM D1003 method. Impact strength was measured according to ASTM D256.

Example  One

80% by weight of acrylic resin (A) having a weight ratio of MMA-CHMA-PMI (methyl methacrylate-cyclohexyl methacrylate-N-phenyl maleimide) in the acrylic resin, and butyl acrylate and styrene The total weight of the resin composition is 100% by weight of the core made of the copolymer of ethylene and 70% by weight of the core-shell type acrylic impact modifier (B) having a methyl methacrylate-cyclohexyl methacrylate ratio of 95: 5. Ethylenebis (oxyethylene) bis- (3- (5) Ethylenebis (oxyethylene) bis- (3- (5-t-butyl-4-hydroxy-m-tolyl) -propionate as a heat stabilizer based on parts by weight 0.2 parts by weight of -tert-butyl-4-hydroxy-m-tolyl) -propionate)) was added to dry blend, and then a heat- and impact-resistant blend in pellet state was prepared at a die temperature of 250 ° C. using a coaxial twin screw extruder. Physical properties evaluated using the prepared pellets are shown in Table 2 below. The.

Example  2

Same as Example 1 except that the monomer content of MMA-CHMA-PMI (methyl methacrylate-cyclohexyl methacrylate-N-phenyl maleimide) in the acrylic resin was adjusted to 88.5: 10: 1.5 After the preparation to evaluate the physical properties are shown in Table 2 below.

Example  3

Same as Example 1 except that the monomer content of MMA-CHMA-PMI (methyl methacrylate-cyclohexyl methacrylate-N-phenyl maleimide) in the acrylic resin was adjusted to 88: 10: 2 After the preparation to evaluate the physical properties are shown in Table 2 below.

Comparative example  One

The monomer content of MMA-CHMA-PMI (methyl methacrylate-cyclohexyl methacrylate-N-phenyl maleimide) in the acrylic resin was adjusted to 100: 0: 0, and the acrylic impact modifier Impact modifiers in which the shell consists of methyl methacrylate Except that the resin composition composed of 20% by weight, was prepared in the same manner as in Example 1 and the physical properties were evaluated and shown in Table 2 below.

Comparative example  2

The monomer content of MMA-CHMA-PMI (methyl methacrylate-cyclohexyl methacrylate-N-phenyl maleimide) in the acrylic resin was adjusted to 90: 10: 0, and the acrylic impact modifier Impact modifiers in which the shell consists of methyl methacrylate Except that the resin composition composed of 20% by weight, was prepared in the same manner as in Example 1 and the physical properties were evaluated and shown in Table 2 below.

Comparative example  3

The monomer content of the MMA-CHMA-PMI (methyl methacrylate-cyclohexyl methacrylate-N-phenyl maleimide) in the acrylic resin was adjusted to 88: 10: 2, and the acrylic impact modifier Impact modifiers in which the shell consists of methyl methacrylate Except that the resin composition composed of 20% by weight, was prepared in the same manner as in Example 1 and the physical properties were evaluated and shown in Table 2 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Acrylic system
Suzy MMA 89 88.5 88 100 90 88 CHMA 10 10 10 0 10 10 PMI One 1.5 2 0 0 2

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Glass transition temperature (Tg) (℃) 117 119 121 105 115 121 Total light transmittance (Tt) (%) 92.8 93.0 92.7 93.2 92.0 92.5 Haze (%) 1.1 1.2 1.2 1.0 2.1 2.2 Impact strength (kgcm / cm) 4.0 3.8 3.6 4.1 4.0 3.7

    Examples 1 to 3, the acrylic resin comprising a copolymer of MMA, CHMA, and PMI of the present invention; And it was confirmed that the acrylic resin composition composed of the impact modifier of the present invention is excellent in heat resistance, permeability, and impact strength.

    On the other hand, through Comparative Example 1 and Table 2, acrylic resin containing MMA without CHMA and PMI; And it was observed that the acrylic resin composition which consists of the impact modifier of the prior art has heat resistance weaker than Examples 1-3.

    In addition, through Comparative Example 2 and Table 2, acrylic resin containing a copolymer of MMA and CHMA without PMI; And it was observed that the acrylic resin composition which consists of the impact modifier of the prior art does not have good permeability.

Also in the case of Comparative Example 3, when the acrylic resin composition was prepared by the impact reinforcing agent of the prior art instead of the impact reinforcing agent of the present invention it was confirmed that the permeability is not good.

Although only described in detail with respect to the described embodiments of the present invention, it will be apparent to those skilled in the art that various modifications and variations are possible within the technical spirit of the present invention, it is natural that such variations and modifications belong to the appended claims. .

Claims (19)

Acrylic resins (A) comprising copolymers of monomers comprising alkyl (meth) acrylates, cyclic (meth) acrylates and acid anhydride monomers or derivatives thereof; And Seed (a) comprising a polymer of a monomer comprising an alkyl methacrylate, an acrylic rubber core (b) surrounding the seed and comprising a copolymer of a monomer comprising an alkyl acrylate and an aromatic vinyl compound, and the core An acrylic resin composition comprising an acrylic impact modifier (B) surrounding and comprising a shell (c) comprising a copolymer of a monomer comprising an alkyl methacrylate and a cyclic (meth) acrylate. The acrylic resin composition according to claim 1, wherein the copolymer forming the shell (c) further comprises an aromatic vinyl compound as a comonomer. The acrylic resin composition according to claim 1, wherein a weight ratio of the acrylic resin (A) and the acrylic impact modifier (B) is 70:30 to 90:10. The acrylic resin composition according to claim 1, wherein the alkyl group of the alkyl (meth) acrylate has 1 to 5 carbon atoms. The method of claim 1, wherein the alkyl (meth) acrylate is methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylic Acrylic resin composition, characterized in that it is selected from the group consisting of latex, butyl acrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate and isobutyl methacrylate. The cyclic (meth) acrylate of claim 1, wherein the cyclic (meth) acrylate is unsubstituted or substituted with an alkyl group having 1 to 5 carbon atoms, a cycloalkyl group having 6 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an aryl group having 6 to 12 carbon atoms. Or (meth) acrylate substituted with a group selected from the group consisting of alkyl groups having 1 to 3 carbon atoms substituted with an aryloxy group, acrylic resin composition. The method of claim 1, wherein the cyclic (meth) acrylate is cyclohexyl methacrylate, benzyl methacrylate, cyclohexyl acrylate, 2-phenoxyethyl acrylate, 3,3,5-trimethylcyclohexyl methacrylate , Phenyl methacrylate or naphthyl methacrylate, acrylic resin composition. The method of claim 1, wherein the acid anhydride monomer or derivative thereof is a monovalent or divalent or higher polyhydric carboxylic acid anhydride, an anhydride represented by the following formula (1) or an imide derivative thereof An acrylic resin composition characterized by the above-mentioned. [Formula 1]

In the above formula, R ₁ and R ₂ are each independently a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. The acrylic resin composition according to claim 8, wherein the imide derivative is N-phenyl maleimide, N-methyl maleimide, N-ethyl maleimide, N-butyl maleimide, or N-cyclohexyl maleimide. . The content of the seed (a) based on the acrylic impact modifier (B) is 1 to 30% by weight, the content of the core (b) is 10 to 70% by weight, the content of the shell (c). Silver is 10 to 80% by weight, acrylic resin composition. The copolymer forming the shell (c) of the acrylic impact modifier (B) is 6 to 60 wt% of alkyl methacrylate and 2 to 10 cyclic (meth) acrylate based on 100% of the total impact modifier. An acrylic resin composition, comprising 2% by weight to 20% by weight of an aromatic vinyl compound. The acrylic resin composition according to claim 1, wherein the alkyl acrylate is an acrylate substituted with an alkyl group having 1 to 5 carbon atoms. The acrylic resin composition according to claim 1, wherein the aromatic vinyl compound is selected from the group consisting of styrene, alphamethyl styrene, paramethyl styrene, and vinyl toluene. The acrylic resin composition according to claim 1, wherein the seeds (a), the core (b), and the shell (c) have a refractive index of 1.49 to 1.51, respectively. The acrylic resin composition according to claim 1, further comprising 0.01 to 0.5 parts by weight of a heat stabilizer based on 100 parts by weight of the acrylic resin composition. The optical or display material containing the acrylic resin composition of any one of Claims 1-15. The optical or display material according to claim 16, wherein the optical or display material is a display screen film. Optical or display apparatus containing the acrylic resin composition of any one of Claims 1-15. The optical or display device according to claim 18, wherein the optical or display device is a TV, a computer monitor, a notebook or a mobile phone.