WO2015009014A1

WO2015009014A1 - Resin mixture

Info

Publication number: WO2015009014A1
Application number: PCT/KR2014/006361
Authority: WO
Inventors: 이종원; 이한나; 류진영; 김우성; 최은주; 최현
Original assignee: 주식회사 엘지화학
Priority date: 2013-07-15
Filing date: 2014-07-15
Publication date: 2015-01-22

Abstract

The present application relates to a resin mixture, a resin copolymer, a resin pellet, a method for preparing a resin-molded product using the same, and a resin-molded product using the same. A resin mixture as embodied in the present application is capable of providing a protective film for a polarizing plate, having an excellent adhesion with a polarizer. In addition, when the resin mixture is used, it is still possible to demonstrate an excellent adhesion with a polarizer while skipping an additional step of coating a primer on the surface of the protective film for a polarizing plate, and therefore, it is possible to reduce production time and costs and to increase productivity.

Description

Resin mixture

The present application relates to a resin mixture, pellets, a method for producing a resin molded article using the same, and a resin molded article.

A polarizing plate is an optical functional film applied to apparatuses, such as a liquid crystal display (LCD) etc., for example.

The polarizing plate includes a polarizer which is a functional sheet capable of extracting only the light vibrating in one direction from the incident light while vibrating in various directions, and is typically a triacetyl cellulose attached to both surfaces of the polarizer by an adhesive or an adhesive. (Triacetyl Cellulose, TAC) -based protective film may be included.

However, a general TAC protective film is expensive and not easy to manufacture. Accordingly, an acrylic protective film or the like is used as a protective film for replacing the TAC protective film. In addition, since the TAC-based fabric film has a hygroscopicity, it is possible to use an aqueous adhesive such as a polyvinyl alcohol adhesive. However, the acrylic protective film generally has a low hygroscopicity and is attached to the polarizer using an ultraviolet curable adhesive instead of the aqueous adhesive. do. However, in this case, the acrylic protective film is not excellent in the adhesive force with the polarizer, coating the primer or the like on one side or both sides of the acrylic protective film to improve the problem.

The present application provides resin mixtures and pellets.

One embodiment of the present application is a first resin; And a second resin having a difference in surface energy or melt viscosity from the first resin, wherein the second resin has 70 to 95 parts by weight of an alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms; To provide a resin mixture which is a polymer of a monomer mixture comprising 5 to 30 parts by weight of the monomer of the formula (1).

[Formula 1]

Where

R ₁ represents hydrogen or an alkyl group having 1 to 4 carbon atoms,

Ar represents phenyl,

R ₂ represents hydrogen or -XR ₆ ,

-X- represents -O- or -OC (O)-, and R <_6> represents a C1-C4 alkyl group here.

Another embodiment of the present application is a core formed of a first resin; And a cell formed of the first resin and the second resin having a difference in surface energy or melt viscosity.

Another embodiment of the present application to melt the resin mixture to form a molten mixture; And processing the melted mixture to form a layered structure.

Another embodiment of the present application is to melt the pellets to form a molten mixture; And processing the melted mixture to form a layered structure.

Another embodiment of the present application is the first resin layer; A second resin layer formed on the first resin layer; And an interfacial layer comprising a first resin and a second resin, the interfacial layer being formed between the first resin layer and the second resin layer,

The second resin, 70 to 95 parts by weight of alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms; And it provides a resin molded article which is a polymer of a monomer mixture comprising 5 to 30 parts by weight of the monomer of the formula (1).

[Formula 1]

Where

R ₁ represents hydrogen or an alkyl group having 1 to 4 carbon atoms,

Ar represents phenyl,

R ₂ represents hydrogen or -XR ₆ ,

-X- represents -O- or -OC (O)-, and R <_6> represents a C1-C4 alkyl group here.

Hereinafter, a resin mixture, a copolymer, a pellet, a manufacturing method of a resin molded article using the same, and a resin molded article according to specific embodiments will be described in detail.

In the above, the "mixture" may be a mixture of two or more different resins. The type of the mixture is not particularly limited, but may include a case in which two or more resins are mixed in one matrix, or a case in which two or more pellets are mixed. Each of the resins may have different physical properties, for example, the physical properties may be surface energy, melt viscosity, or solubility parameter.

"Melt processing" means a process of melting a resin mixture at a temperature above the melting temperature (Tm) to form a melt blend, and forming a desired molded article using the melt mixture, for example, injection Molding, extrusion molding, blow molding, transfer molding, film blowing, fiber spinning, calendering thermoforming or foam molding.

"Resin molded article" means a pellet or product formed from a resin mixture, and the resin molded article is not particularly limited, but may be, for example, an automobile part, an electronic device part, a mechanical part, a functional film, a toy, or a pipe. have.

"Layer separation" may mean that a layer formed substantially by one resin is positioned or arranged on a layer formed substantially by another resin. Substantially, the layer formed by one resin may mean that one type of resin does not form a sea-island structure and is continuously present throughout one layer. The sea-level structure means that the phase separated resin is partially distributed in the whole resin mixture. In addition, "substantially formed" may mean that only one resin is present in one layer, or that one resin is rich.

In one example, the resin mixture may be separated by melt processing. Thereby, a resin molded article having a specific function, for example, excellent adhesiveness, can be produced without a separate process such as coating and plating. Therefore, the resin molded article can have improved adhesiveness, and the production cost and time of the resin molded article can be reduced when using the resin mixture.

Layer separation of the resin mixture may occur due to the difference in physical properties between the first resin and the second resin and / or the molecular weight distribution of the second resin. Here, the physical properties may be, for example, surface energy, melt viscosity or solubility parameter. In the present specification, a mixture of resins including two kinds of resins will be described, but it will be apparent to those skilled in the art that three or more kinds of resins having different physical properties can be mixed and separated by melt processing.

According to one embodiment, the resin mixture may include a first resin and a second resin having a surface energy difference of 0.1 to 35 mN / m at 25 ° C. from the first resin.

The surface energy difference between the first resin and the second resin is 0.1 to 35 mN / m, 0.1 to 30 mN / m, 0.1 to 20 mN / m, 0.1 to 15 mN / m, 0.1 to 7 mN / m at 25 ℃ , 1 to 35 mN / m, 1 to 30 mN / m, 2 to 20 mN / m, 3 to 15 days. In the case of using the first and second resins having a surface energy difference in this range, the second resin can easily move to the surface without the first and second resins peeling off, and the delamination phenomenon can easily occur.

The resin mixture of the first resin and the second resin having a surface energy difference of 0.1 to 35 mN / m at 25 ° C. may be layer separated by melt processing. As one example, when the resin mixture of the first resin and the second resin is melt processed and exposed to air, the first resin and the second resin may be separated by a hydrophobic difference. In particular, since the second resin having a lower surface energy than the first resin has high hydrophobicity, the second resin can be moved in contact with air to form a second resin layer located on the air side. In addition, the first resin may be placed on the side opposite to the air while contacting the second resin. Thus, layer separation occurs between the first resin and the second resin of the resin mixture.

The resin mixture may be separated into two or more layers. As one example, the resin mixture comprising the first resin and the second resin may have three layers, for example, a second resin layer, when two opposite surfaces of the melt processed resin mixture are exposed to air. It can be separated into a / first resin layer / a second resin layer. On the other hand, when only one side of the melt processed resin mixture is exposed to air, the resin mixture may be separated into two layers, for example, a second resin layer / first resin layer. In addition, when the resin mixture comprising the first resin, the second resin and the third resin having a surface energy difference is melt processed, the melt processed resin mixture has five layers, for example, a third resin layer / agent. The layer can be separated into two resin layers / first resin layer / second resin layer / third resin layer. In addition, when all surfaces of the melt-processed resin mixture are exposed to air, the resin mixture may be layered in all directions to form a core-shell structure.

According to another embodiment, the resin mixture comprises a first resin; And a second resin having a melt viscosity difference of 0.1 to 3000 pa * s at a shear rate of 100 to 1000 s ⁻¹ and a processing temperature of the resin mixture.

The difference in melt viscosity of the first resin and the second resin is 0.1 to 3000 pa * s, 1 to 2000 pa * s, 1 to 1000 pa * at a shear rate of 100 to 1000 s ⁻¹ and a processing temperature of the resin mixture. s, 1 to 500 pa * s, 50 to 500 pa * s, 100 to 500 pa * s, 200 to 500 pa * s or 250 to 500 pa * s. In the case of using the first and second resins having a difference in melt viscosity in this range, the second resin can easily move to the surface and the layer separation phenomenon can easily occur without the first and second resins peeling off.

The resin mixture of the first resin and the second resin having a melt viscosity difference of 0.1 to 3000 pa * s at a shear rate of 100 to 1000 s ⁻¹ and a processing temperature of the resin mixture is layered due to the difference in melt viscosity after melt processing. Can be separated. As one example, when the resin mixture of the first resin and the second resin is melt processed and exposed to air, the first resin and the second resin may be separated by the fluidity difference. In particular, since the second resin having a lower melt viscosity than the first resin has high fluidity, the second resin can be moved in contact with air to form a second resin layer located on the air side. In addition, the first resin may be placed on the side opposite to the air while contacting the second resin. Thus, layer separation occurs between the first resin and the second resin of the resin mixture.

The melt viscosity can be measured by capillary flow, which means shear viscosity (pa * s) depending on the specific processing temperature and shear rate (/ s).

The 'shear rate' refers to a shear rate applied when the resin mixture is processed, and the shear rate may be adjusted between 100 and 1000 s ⁻¹ depending on the processing method. Control of the shear rate according to the processing method will be apparent to those skilled in the art.

The 'processing temperature' means a temperature for processing the resin mixture. For example, when the resin mixture is used for melt processing such as extrusion or injection, it means a temperature applied to the melt processing step. The processing temperature can be adjusted according to the resin applied to melt processing such as extrusion or injection. For example, in the case of the resin mixture including the first resin of the ABS resin and the second resin obtained from the acrylic monomer, the processing temperature may be 210 to 270 ° C.

According to another embodiment of the invention, the first resin; And a second resin having a difference in solubility parameters from 0.001 to 10.0 (J / cm ³ ) ^1/2 at 25 ° C., may be provided.

The difference between the solubility parameters of the first resin and the second resin is 0.001 to 10.0 (J / cm ³ ) ^1/2 , 0.01 to 5.0 (J / cm ³ ) ^1/2 , 0.01 to 3.0 ( J / cm ³ ) ^1/2 , 0.01 to 2.0 (J / cm ³ ) ^1/2 , 0.1 to 1.0 (J / cm ³ ) ^1/2 , 0.1 to 10.0 (J / cm ³ ) ^1/2 , 3.0 to 10.0 (J / cm ³ ) ^1/2 , 5.0 to 10.0 (J / cm ³ ) ^1/2 or 3.0 to 8.0 (J / cm ³ ) ^1/2 . These solubility parameters are inherent properties of the resins which show the solubility according to the polarity of each resin molecule, and solubility parameters for each resin are generally known. When the difference in solubility parameter is ^less than 0.001 (J / cm ³ ) ^1/2 , the first resin and the second resin are easily mixed, so that the layer separation phenomenon is difficult to occur easily, and the difference in solubility parameter is 10.0 (J / cm ³ ) If greater than ^1/2 , the first resin and the second resin may not be bonded and may be peeled off.

The upper limit and / or lower limit of the difference in solubility parameters may be any value within the range of 0.001 to 10.0 (J / cm ³ ) ^1/2 , and may be dependent on the physical properties of the first resin. In particular, when the first resin is used as the base resin and the second resin is used as a functional resin for improving the surface properties of the first resin, the second resin has a difference in solubility parameter between the first resin and the second resin at 25 ° C. Can be selected to be from 0.001 to 10.0 (J / cm ³ ) ^1/2 . As one example, the difference in solubility parameter may be selected in consideration of the miscibility of the second resin in the melt mixture of the first resin and the second resin.

At 25 ° C., the resin mixture of the first resin and the second resin having a solubility parameter difference of 0.001 to 10.0 (J / cm ³ ) ^1/2 may be layer separated after melt processing due to the difference in solubility parameters. As one example, when the resin mixture of the first resin and the second resin is melt processed and exposed to air, the first resin and the second resin may be separated by the degree of miscibility. In particular, the second resin having a difference in solubility parameter of 0.001 to 10 (J / cm ³ ) ^1/2 at 25 ° C. relative to the first resin may not be mixed with the first resin. Therefore, if the second resin additionally has a lower surface tension or lower melt viscosity than the first resin, the second resin can be moved in contact with air to form a second resin layer located on the air side. In addition, the first resin may be placed on the side opposite to the air while contacting the second resin. Thus, layer separation occurs between the first resin and the second resin of the resin mixture.

In the resin mixture, the first resin is a resin mainly determining the physical properties of the desired molded article, and may be selected according to the type of the desired molded article and the process conditions used. As such a first resin, a general synthetic resin can be used without particular limitation.

As a 1st resin, For example, Styrene-type resins, such as an acrylonitrile butadiene styrene (ABS) resin, a polystyrene resin, an acrylonitrile styrene acrylate (ASA) resin, or a styrene-butadiene-styrene block copolymer; Polyolefin resins such as high density polyethylene resin, low density polyethylene resin or polypropylene resin; Thermoplastic elastomers such as ester-based thermoplastic elastomers or olefin-based thermoplastic elastomers; Polyoxyalkylene resins such as polyoxymethylene resin or polyoxyethylene resin; Polyester resins such as polyethylene terephthalate resins or polybutylene terephthalate resins; Polyvinyl chloride resins; Polycarbonate resins; Polyphenylene sulfide resin; Vinyl alcohol-based resins; Polyamide-based resins; Acrylate resins; Engineering plastics; These copolymers or mixtures thereof are mentioned. As the engineering plastics, plastics exhibiting excellent mechanical and thermal properties may be used. For example, polyetherketone, polysulfone, polyimide and the like can be used as the engineering plastics. In one example, as the first resin, a copolymer obtained by polymerizing acrylonitrile, butadiene, styrene and an acrylic monomer may be used.

In one example, the first resin is an alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms; The monomer of Formula 1; And it may be a polymer of a monomer mixture comprising a monomer of formula (2).

[Formula 1]

[Formula 2]

Where

R ₁ independently represents hydrogen or an alkyl group having 1 to 4 carbon atoms,

Ar represents phenyl,

R ₂ represents hydrogen or -XR ₆ ,

Wherein -X- represents -O- or -OC (O)-, R ₆ represents an alkyl group having 1 to 4 carbon atoms,

Y represents oxygen or NR ₁₀ ,

R ₁₀ represents hydrogen, an alkyl group having 1 to 12 carbon atoms, or a cycloalkyl group having 3 to 8 carbon atoms.

In one example, the monomer of Formula 1 may be styrene or alpha-methyl styrene, and the monomer of Formula 2 may be cyclohexyl maleimide or maleic anhydride, but is not limited thereto.

In addition, the monomer mixture forming the polymer of the first resin is 85 to 98 parts by weight of an alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms; 1 to 5 parts by weight of the monomer of Formula 1; And it may include 3 to 10 parts by weight of the monomer of formula (2). When the alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms is included in an amount of less than 85 parts by weight, the compatibility with the second resin to be described later is too bad, the peeling phenomenon on the surface of the first resin and the second resin May appear.

As the second resin in the resin mixture, a resin exhibiting the difference in physical properties as described above in relation to the first resin and imparting good compatibility with the first resin and an adhesive can be used. .

In one example, the second resin,

70 to 95 parts by weight of alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms; And

It may be a polymer of a monomer mixture including 5 to 30 parts by weight of the monomer of Formula 1.

[Formula 1]

Where

R ₁ represents hydrogen or an alkyl group having 1 to 4 carbon atoms,

Ar represents phenyl,

R ₂ represents hydrogen or -XR ₆ ,

-X- represents -O- or -OC (O)-, and R <_6> represents a C1-C4 alkyl group here.

In addition, in the above formula, for example,

R ₁ represents hydrogen or a methyl group,

Ar represents phenyl,

R ₂ represents hydrogen or -XR ₆ ,

Where -X- represents -O- or -OC (O)-,

R ₆ may represent a methyl group or an ethyl group.

The compatibility between the first resin and the second resin is a layer separation inducing factor if the compatibility is too good, the layer separation efficiency between the first resin and the second resin is reduced, if the compatibility is not very good, peel off from the surface or inside the molding Can form large domains. Therefore, proper compatibility between the first resin and the second resin is required for effective layer separation. Accordingly, in the second resin of the present application, by including a specific monomer in consideration of compatibility with the first resin in an appropriate content, the above object can be achieved.

In one example, the monomer mixture of the second resin is 70 to 95 parts by weight, for example 70 to 90 parts by weight, 75 to 75 parts by weight of an alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms or By including it in an amount of 75 to 90 parts by weight, it can exhibit excellent compatibility with the first resin. For example, the alkyl (meth) acrylate monomer having an alkyl group having 1 to 14 carbon atoms is a component included in the monomer mixture of the first resin, and is used to ensure compatibility between the first resin and the second resin. Ingredient.

The monomer of Formula 1 is included in the monomer mixture of the second resin as a component for effectively separating the layers. The monomer of Formula 1 may be, for example, a component having low compatibility with the monomer of Formula 2 included in the monomer mixture of the first resin, and may be included in the monomer mixture of the second resin. The monomer of Formula 1 may be included in an amount of 5 to 30 parts by weight, 10 to 30 parts by weight, or 10 to 25 parts by weight in the monomer mixture of the second resin, when included in more than 30 parts by weight, the first resin The compatibility with too much worsens and peeling phenomenon may appear on the surface of a 1st resin and a 2nd resin.

In one example, the monomer of Formula 1 may be styrene unsubstituted or substituted with one or more substituents selected from the group consisting of methyl, methoxy, ethoxy and acetoxy, for example, excellent adhesion to the polarizer In view of the above, acetoxy styrene, methoxy styrene, methyl 4-vinylbenzoate and the like can be exemplified, but is not limited thereto. By including the monomer of Formula 1 in the second resin, it is possible to ensure excellent adhesion with the polarizer.

When the resin molded article formed by the resin mixture is used as a protective film for a polarizing plate, it can replace a TAC-based film or an acrylic protective film that has been used in the past, in particular, in the case of a conventional acrylic protective film, the adhesiveness with the polarizer In order to secure the primer, etc. had to be coated on the surface through a separate coating process, according to the resin mixture and the protective film prepared according to the present application, the additional primer coating step on the surface of the protective film for polarizing plates can be omitted In addition, it is possible to exhibit excellent adhesion with the polarizer can reduce the production time and cost, and increase the productivity.

In one example, the weight average molecular weight (Mw) of the second resin may be about 5,000 to 200,000. In another example, the weight average molecular weight of the second resin is 10,000 to 200,000, 1.50,000 to 200,000, 20,000 to 200,000, 0.50,000 to 180,000, 0.50,000 to 150,000, 0.50,000 to 120,000, 10,000 to 180,000, 1.50,000 to 150,000, or 20,000 to 120,000. When the second resin having a weight average molecular weight in this range is applied to, for example, a resin mixture for melt processing, the second resin may have appropriate fluidity and layer separation may easily occur.

In addition, in one example, the molecular weight distribution (PDI) of the second resin may be controlled in the range of 1 to 2.5, 1 to 2.2, 1.5 to 2.5, or 1.5 to 2.2. When the second resin having a molecular weight distribution in this range is applied to, for example, a resin mixture for melt processing, the content of low molecular weight and / or high molecular weight which prevents occurrence of delamination in the second resin is reduced, thereby making layer separation easier. Can happen.

In one example, the resin mixture may include 0.1 to 50 parts by weight of the second resin based on 100 parts by weight of the first resin. In another example, the resin mixture may include 1 to 30 parts by weight, 1 to 20 parts by weight, or 1 to 15 parts by weight based on 100 parts by weight of the first resin. When the content includes the first resin and the second resin, it is possible to induce a layer separation phenomenon, it is possible to provide an economical resin mixture by appropriately controlling the content of the second resin that is relatively expensive compared to the first resin.

The above resin mixture can be prepared into pellets by extrusion. In the pellet manufactured using the resin mixture, the first resin may form a core, and the second resin may be separated from the first resin to form a shell.

According to one embodiment, the pellet comprises a core formed of the first resin; And 70 to 95 parts by weight of an alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms having a difference in surface energy, melt viscosity or solubility parameter from the first resin; And it provides a pellet comprising a cell formed of a second resin which is a polymer of a monomer mixture comprising 5 to 30 parts by weight of the monomer of Formula 1.

In addition, as described above, the first resin and the second resin may have different surface energy, melt viscosity, or solubility parameters. For example, the first resin and the second resin may have a surface energy difference of 0.1 to 35 mN / m at 25 ° C .; Or at a shear rate of 100 to 1000 s ⁻¹ and a melt temperature of 0.1 to 3000 pa * s at the processing temperature of the pellets.

Since the type and physical properties of the first resin and the second resin have already been described in detail, specific details will be omitted.

On the other hand, the resin mixture or pellets described above may be melt processed to provide a resin molded article having a layered structure.

According to one embodiment, melting the resin mixture to form a melt blend (melt blend); And processing the melted mixture to form a layered structure.

As described above, due to the difference in physical properties between the first resin and the second resin, a layer separation phenomenon may occur in the process of melt processing the resin mixture, and due to this layer separation phenomenon, pellets or It can have the effect of selectively coating the surface of the molded article.

In particular, 70 to 95 parts by weight of an alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms as the second resin; And when using the polymer of the monomer mixture containing 5 to 30 parts by weight of the monomer of Formula 1, the shell portion having a relatively low surface energy or melt viscosity during the melt processing process is located on the surface of the resin molded article mechanical properties and surface A resin molded article having improved characteristics can be provided.

Melt processing the resin mixture may be performed under shear stress. For example, the melt processing step may be performed by an extrusion and / or injection processing method.

In addition, the step of melt processing the resin mixture may vary the temperature applied according to the type of the first resin and the second resin used. For example, when styrene resin is used as the first resin and acrylic resin is used as the second resin, the melt processing temperature may be controlled to about 210 to 270 ° C.

The method of manufacturing a resin molded article may further include curing the resultant obtained by melt processing the resin mixture, that is, the melt processed product of the resin mixture. The curing can be, for example, thermosetting or UV curing. In addition, the resin molded article may be further subjected to chemical or physical treatment.

In one example, the method of manufacturing a resin molded article may further include preparing a second resin before melting the resin mixture to form a molten mixture. 2nd resin can provide a specific function, for example, the outstanding adhesiveness to the surface layer of a resin molded article. Since the contents related to the preparation of the second resin have already been described, specific details are omitted.

According to another embodiment, the method for producing a resin molded article may include melting a pellet to form a molten mixture; And processing the melt mixture to form a layered structure.

In one example, the pellet may be prepared by melt processing such as extrusion of the resin mixture described above. For example, when extruding a resin mixture comprising the first resin and the second resin, the second resin having a higher hydrophobicity than the first resin moves in contact with air to form a surface layer of the pellet. One resin may be located in the center of the pellet to form a core. The pellets thus prepared can be manufactured into a resin molded article by melt processing such as injection. However, the present invention is not limited thereto, and in another example, the resin mixture may be manufactured into a resin molded article by melt processing such as direct injection or the like.

On the other hand, according to another embodiment, the resin molded article is a first resin layer, a second resin layer formed on the first resin layer and an interface layer formed between the first resin layer and the second resin layer. It may include. The interface layer may include first and second resins.

As for the resin molded article manufactured from the resin mixture containing the specific 1st resin and the said 2nd resin which has a physical property difference with the said 1st resin, a 1st resin layer is located inside and a 2nd resin layer is resin It may be a layered structure formed on the surface of the molded article.

In particular, when using the above-mentioned resin as the second resin, it is possible to further improve the adhesive force of the molded article.

The first resin layer mainly includes the first resin, determines physical properties of the molded article, and may be located inside the resin molded article. In addition, the 'second resin layer' may mainly include the second resin, and may be positioned outside the resin molded article to impart a predetermined function to the surface of the molded article.

Since specific details of the first resin and the second resin have been described above, the description of the related contents will be omitted.

The resin molded article may include an interface layer formed between the first resin layer and the second resin layer and containing a mixture of the first resin and the second resin. The interfacial layer may be formed between the separated first resin layer and the second resin layer to serve as an interface, and may include a mixture of the first resin and the second resin. The blend may be in a state in which the first resin and the second resin are physically or chemically bonded, and the first resin layer and the second resin layer may be bonded through the blend.

The resin molded article may be formed in a structure in which the first resin layer and the second resin layer are divided by such an interface layer, and the second resin layer is exposed to the outside. For example, the molded article may include the first resin layer; Interfacial layer; And a structure in which the second resin layer is sequentially stacked, and may have a structure in which an interface and a second resin are stacked on upper and lower ends of the first resin. In addition, the resin molded article may include a structure in which the interface and the second resin layer sequentially surround the first resin layer having various three-dimensional shapes, for example, spherical, circular, polyhedral, sheet, and the like.

The layer separation phenomenon appearing in the resin molded article seems to be due to the production of a resin molded article by applying a specific first resin and a second resin having different physical properties. Examples of such different physical properties include surface energy or melt viscosity. Details of such differences in physical properties are as described above.

In one example, the first resin layer, the interfacial layer, and the second resin layer may be identified using an SEM after etching the fracture surface using THF vapor after the specimen is subjected to a low temperature impact test. For the measurement of the thickness of each layer, the specimen is cut with a diamond knife using a microtoming device to make a smooth cross section, and then the smooth cross section is etched using a solution that can selectively dissolve the second resin better than the first resin. The etched cross-section is different in the degree of melting depending on the content of the first resin and the second resin, and when the cross-section is viewed from the surface at 45 degrees using the SEM, the first resin layer, the second resin layer, The interfacial layer and the surface can be observed and the thickness of each layer can be measured. In one example, 1,2-dichloroethane solution (10% by volume, in EtOH) was used as a solution for selectively dissolving the second resin, but this is illustrative and the solubility of the second resin is higher than that of the first resin. The solution is not particularly limited, and those skilled in the art can appropriately select and apply a solution according to the type and composition of the second resin.

The interfacial layer is 1 to 95%, 10 to 95%, 20 to 95%, 30 to 95%, 40 to 95%, 50 to 95%, 60 to 95%, or the total thickness of the second resin layer and the interface layer, or It may have a thickness of 60 to 90%. If the interfacial layer is 0.01-95% of the total thickness of the second resin layer and the interfacial layer, the interfacial bonding force between the first resin layer and the second resin layer is excellent, so that peeling of both layers does not occur, and the second resin layer Due to this, the surface properties can be greatly improved. On the contrary, if the interface layer is too thin as compared to the second resin layer, the bonding force between the first resin layer and the second resin layer is low, so that peeling of both layers may occur. The effect of the improvement of properties may be insignificant.

The second resin layer may have a thickness of 0.01 to 30%, 0.01 to 20%, 0.01 to 10%, 0.01 to 5%, 0.01 to 3%, 0.01 to 1% or 0.01 to 0.1% relative to the total resin molded article. . As the second resin layer has a range of thicknesses, it is possible to impart improved adhesion to the surface of the molded article. If the thickness of the second resin layer is too thin, it may be difficult to sufficiently improve the surface properties of the molded article. If the thickness of the second resin layer is too thick, the physical properties of the functional resin itself may be reflected in the resin molded article, thereby changing the mechanical properties of the first resin.

In the resin molded article of the structure mentioned above, the component of a 1st resin layer can be detected by the infrared spectroscopy IR on the surface of a 2nd resin layer.

In the above, the surface of the second resin layer means a surface exposed to the outside (for example, air) rather than the first resin layer.

Details of the first resin, the second resin, and the difference in physical properties of the first resin and the second resin have already been described above, and thus description of the related content will be omitted. In addition, in the present specification, the difference in physical properties between the first resin and the second resin may mean a difference in physical properties between the first resin and the second resin or a difference in physical properties between the first resin layer and the second resin layer.

In one example, the resin molded article can be used to provide a protective film for a polarizing plate. For example, the resin molded article may be used in place of a TAC-based protective film that has been conventionally used, and the polarizing plate may be provided with the second resin layer of the resin molded article attached to one or both sides of the polarizer. have. The kind of the polarizer is not particularly limited, and for example, a film made by containing a polarizing component such as iodine or a dichroic dye in a film made of polyvinyl alcohol-based resin and stretching can be used. As the polyvinyl alcohol-based resin, polyvinyl alcohol, polyvinyl formal, polyvinyl acetal or saponified product of ethylene-vinyl acetate copolymer may be used. In this case, the degree of polymerization of the polyvinyl alcohol-based resin may be 100 to 5,000, preferably 1,400 to 4,000. In addition, the thickness of the polarizer may be appropriately selected according to the use of the liquid crystal display device and the like, and is usually formed in a thickness of 5 μm to 80 μm, but is not limited thereto. The method for attaching the protective film for polarizing plates produced by the resin molded article of the present application to the polarizer is not particularly limited, and for example, polyvinyl alcohol-based adhesives or ultraviolet curable adhesives, including polyvinyl alcohol-based resins and crosslinking agents, For example, from oligomers such as radical polymerizable adhesives or epoxy resin vinyl esters polymerized from hydroxyl group-containing acrylates, epoxy acrylates, urethane acrylates, oxetane acrylates, polyester acrylates or silicone acrylates. The second resin layer and the polarizer of the resin molded article can be attached by using known adhesive means such as induced cationic polymerizable adhesive. When the resin molded article formed by the resin mixture is used as a protective film for a polarizing plate, it can replace a TAC-based film or an acrylic protective film that has been used in the past, in particular, in the case of a conventional acrylic protective film, the adhesiveness with the polarizer In order to ensure a primer or the like on the surface through a separate coating process, according to the resin mixture and the protective film prepared according to the present application, the second number comprising a second resin having excellent affinity with the adhesive The layer is formed by layer separation in the melt processing process, and thus, an additional primer coating step can be omitted on the surface of the protective film for polarizing plate, and excellent adhesion with the polarizer can be produced, thereby reducing production time and cost. And increase productivity.

Exemplary resin mixture of the present application can provide a protective film for a polarizing plate excellent in adhesion to the polarizer. In addition, when the resin mixture is used, an additional primer coating step may be omitted on the surface of the protective film for the polarizing plate, and thus, excellent adhesion with the polarizer may be exhibited, thereby reducing production time and cost, and increasing productivity. .

Figure 1 shows a layered cross-sectional SEM image of the resin molded article prepared in Example 4.

Figure 2 shows a cross-sectional shape SEM photograph of the resin molded article prepared in Comparative Example 1.

3 shows an exemplary polarizer of the present application.

Hereinafter, the resin mixture will be described in detail with reference to Examples and Comparative Examples, but the scope of the resin mixture is not limited to the examples given below.

제조예 - 제 2 수지의 제조Preparation Example-Preparation of Second Resin

제조예 1Preparation Example 1

1674 g of solvent methyl ethyl ketone, 810 g of monomer methyl methacrylate (MMA), 90 g of styrene, and 1.17 g of n-dodecyl mercabtane (n-DDM), a chain transfer agent, were added to the reactor. After the composition, 1.8 g of azobisisobutyronitrile (AIBN) was added as an initiator, and the mixture was stirred at a rate of 400 ppm. After the polymerization was conducted at a reaction temperature of 70 ° C. for 18 hours, it was precipitated in normal hexane, washed and dehydrated three more times, and dried in an oven at 80 ° C.

제조예 2Preparation Example 2

A second resin was prepared in the same manner as in Preparation Example 1, except that 675 g of methyl methacrylate and 225 g of styrene were used as the monomer.

제조예 3Preparation Example 3

A second resin was prepared in the same manner as in Preparation Example 1, except that 675 g of methyl methacrylate and 225 g of acetoxy styrene were used as monomers.

제조예 4Preparation Example 4

A second resin was prepared in the same manner as in Preparation Example 1, except that 675 g of methyl methacrylate, 180 g of styrene, and 45 g of acetoxy styrene were used as the monomer.

제조예 5Preparation Example 5

A second resin was prepared in the same manner as in Preparation Example 1, except that 675 g of methyl methacrylate and 225 g of methoxystyrene were used as monomers.

제조예 6Preparation Example 6

A second resin was prepared in the same manner as in Preparation Example 1, except that 675 g of methyl methacrylate, 180 g of styrene, and 45 g of methoxystyrene were used as the monomer.

제조예 7Preparation Example 7

A second resin was prepared in the same manner as in Preparation Example 1, except that 900 g of methyl methacrylate was used as the monomer.

제조예 8Preparation Example 8

A second resin was prepared in the same manner as in Preparation Example 1, except that 450 g of methyl methacrylate and 450 g of styrene were used as monomers.

제조예 9Preparation Example 9

A second resin was prepared in the same manner as in Production Example 1, except that 450 g of methyl methacrylate and 450 g of acetoxystyrene were used as the monomer.

제조예 10Preparation Example 10

A second resin was prepared in the same manner as in Preparation Example 1, except that 450 g of methyl methacrylate and 450 g of methoxystyrene were used as monomers.

실시예 1Example 1

After mixing 90 parts by weight of the first resin (a thermoplastic resin consisting of 91 parts by weight of methyl methacrylate, 6 parts by weight of cyclohexylmaleimide and 3 parts by weight of alphamethylstyrene) with 10 parts by weight of the second resin prepared in Preparation Example 1 The pellet was extruded at a temperature of 250 ° C. in a twin screw extruder (Leistritz). In addition, the pellets were manufactured using an extruder having a T-die gap of 1 t (EM EM Korea) to produce an extruded film having a film thickness of about 180 to 210 μm at a temperature of 250 ° C. The extruded film was biaxially stretched in the MD and TD directions at a temperature of 135 ° C. to prepare a stretched film having a thickness of about 50 μm.

The stretched film containing the second resin and the polarizer is laminated using an adhesive, and has a structure of a stretched film containing a second resin, a stretched film / adhesive / PVA / adhesive / a second resin as shown in Figure 3 After the laminate was produced, ultraviolet rays were irradiated to cure the adhesive to prepare a polarizing plate.

실시예 2Example 2

A specimen was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparation Example 2 was mixed with 90 parts by weight of the same first resin as used in Example 1.

실시예 3Example 3

A specimen was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparation Example 3 was mixed with 90 parts by weight of the same first resin as used in Example 1.

실시예 4Example 4

A specimen was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparation Example 4 was mixed with 90 parts by weight of the same first resin as used in Example 1.

실시예 5Example 5

A specimen was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparation Example 5 was mixed with 90 parts by weight of the same first resin as used in Example 1.

실시예 6Example 6

A specimen was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparation Example 6 was mixed with 90 parts by weight of the same first resin as used in Example 1.

비교예 1Comparative Example 1

100 parts by weight of the first resin pellets used in Example 1 were dried in an oven, and the pellets were extruded in the same manner as in Example 1 to prepare an extruded film. The extruded film was stretched in the same manner as in Example 1 to prepare a stretched film.

비교예 2Comparative Example 2

A specimen was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparation Example 7 was mixed with 90 parts by weight of the same first resin as used in Example 1.

비교예 3Comparative Example 3

A specimen was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparation Example 8 was mixed with 90 parts by weight of the same first resin as used in Example 1.

비교예 4Comparative Example 4

A specimen was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparation Example 9 was mixed with 90 parts by weight of the same first resin as used in Example 1.

비교예 5Comparative Example 5

A specimen was prepared in the same manner as in Example 1, except that 10 parts by weight of the second resin obtained in Preparation Example 10 was mixed with 90 parts by weight of the same first resin as used in Example 1.

Physical properties in the Examples and Comparative Examples were evaluated in the following manner.

1. 광학 특성(Haze 및 Transmittance)의 측정1. Measurement of optical properties (Haze and Transmittance)

For the stretched film, haze and transmittance were measured using a haze meter HM-150 (Murakami Color Research Laboratory).

2. 용융 점도의 측정2. Measurement of Melt Viscosity

Melt viscosity was measured using a capillary rheometer (Capillary Rheometer 1501, Gottfert).

Specifically, after attaching a capillary die to the barrel (Barrel), the resin obtained in Example or Comparative Example was divided and filled three times. And, the shear viscosity (shear viscosity, pa * s) according to the shear rate (shear rate) at a processing temperature of 250 ℃ was measured.

3. 접착력의 측정3. Measurement of adhesion

In order to evaluate the adhesive force between the polarizer and the protective film in the polarizing plate, a polarizing plate having a width of 18 mm was prepared. Specifically, the polyvinyl alcohol-based resin film is stretched, dyed with iodine, and then treated with a boric acid aqueous solution, the specimen prepared in Examples and Comparative Examples as a protective film on one surface of the polarizer prepared of the specimen The polarizing plate was prepared by adhering using a cation and a radically polymerizable adhesive so that a 2nd resin layer may face the polarizer side. With respect to the prepared polarizing plate, using a texture anlyze equipment (MHK Co., Ltd.) was measured the peel force of 90 ° at 300 mm / min conditions, as shown in Figure 3, the adhesive force between the polarizer and the protective film of the UV irradiation side Was measured. The peel force described the average value after 3 measurements.

4. 단면 형상 관찰4. Observation of section shape

The specimens of Examples and Comparative Examples were subjected to a low temperature impact test, and then the fracture surfaces were etched using THF vapor and the cross-sectional shapes separated by SEM (manufacturer: Hitachi, model name: S-4800) were observed.

The observed cross-sectional shape was evaluated according to the following criteria.

(Circle): The state in which complete delamination was observed

△: not enough layer separation

× : no delamination

5. 표면 에너지의 측정5. Measurement of surface energy

According to the Owens-Wendt-Rabel-Kaelble method, surface energy was measured using a Drop Shape Analyzer (DSA100 manufactured by KRUSS).

Specifically, the resin obtained in Example or Comparative Example was dissolved in methyl ethyl ketone solvent by 15% by weight, and then bar coated on LCD glass. Then, the coated LCD glass was pre-dried for 2 minutes in an oven at 60 ℃, and dried for 1 minute in an oven at 90 ℃.

After drying (or curing), deionized water and diiodomethane were dropped 10 times on the coated surface to obtain an average value of the contact angle, and the surface energy was obtained by substituting numerical values into the Owens-Wendt-Rabel-Kaelble method.

Table 1

	Surface energy difference (mN / m)	Optical properties		Adhesive force (N / cm ² )	Phase separation	Melt Viscosity Difference (pa * s)
	Surface energy difference (mN / m)	Haze	T (%)	Adhesive force (N / cm ² )	Phase separation	Melt Viscosity Difference (pa * s)
Example 1	3	0.2	93.8	2.2	○	900
Example 2	5	0.2	93.7	2.5	○	1010
Example 3	5	0.2	93.9	2.4	○	990
Example 4	6	0.2	93.9	2.7	○	995
Example 5	5	0.2	93.6	2.3	○	985
Example 6	5	0.2	93.7	2.6	○	990
Comparative Example 1	-	0.2	93.9	2	×	-
Comparative Example 2	2	0.2	93.7	2.5	×	1140
Comparative Example 3	9	0.2	93.8	2.2	○	930
Comparative Example 4	3	0.2	93.8	2.1	○	920
Comparative Example 5	3	0.2	93.7	2	○	915

Claims

First resin; And

A second resin which is an acrylic polymer having a difference in surface energy, melt viscosity or solubility parameter from the first resin,

The second resin is

70 to 95 parts by weight of alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms; And

A resin mixture which is a polymer of a monomer mixture comprising 5 to 30 parts by weight of a monomer of Formula 1:

[Formula 1]

Where

R 1 represents hydrogen or an alkyl group having 1 to 4 carbon atoms,

Ar represents phenyl,

R 2 represents hydrogen or -XR 6 ,

-X- represents -O- or -OC (O)-, and R <6> represents a C1-C4 alkyl group here.
The resin mixture according to claim 1, wherein the second resin has a surface energy difference of 0.1 to 35 mN / m from the first resin at 25 ° C.
The resin mixture according to claim 1, wherein the second resin has a difference in melt viscosity of 0.1 to 3000 pa * s at a shear rate of 100 to 1000 s -1 and processing temperature of the resin mixture.
The resin mixture according to claim 1, wherein the second resin has a solubility parameter difference of 0.001 to 10.0 (J / cm 3 ) 1/2 at 25 ° C.
The method of claim 1, wherein the first resin is a styrene resin, a polyolefin resin, a thermoplastic elastomer, a polyoxyalkylene resin, a polyester resin, a polyvinyl chloride resin, a polycarbonate resin, a polyphenylene sulfide resin, A resin mixture, which is a vinyl alcohol resin, a polyamide resin, an acrylate resin, an engineering plastic, a copolymer thereof, or a mixture thereof.
The method of claim 1 wherein the first resin is

Alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms;

The monomer of Formula 1; And

A resin mixture which is a polymer of a monomer mixture comprising a monomer of formula

[Formula 1]

[Formula 2]

Where

R 1 represents hydrogen or an alkyl group having 1 to 4 carbon atoms,

Ar represents phenyl,

R 2 represents hydrogen or -XR 6 ,

Wherein -X- represents -O- or -OC (O)-, R 6 represents an alkyl group having 1 to 4 carbon atoms,

Y represents oxygen or NR 10 ,

R 10 represents hydrogen, an alkyl group having 1 to 12 carbon atoms, or a cycloalkyl group having 3 to 8 carbon atoms.
The method of claim 6 wherein the monomer mixture is

85 to 98 parts by weight of alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms;

1 to 5 parts by weight of the monomer of Formula 1; And

Resin mixture comprising 3 to 10 parts by weight of the monomer of formula (2).
The resin mixture according to claim 6, wherein the monomer of formula 1 is styrene or alpha-methyl styrene, and the monomer of formula 2 is cyclohexyl maleimide or maleic anhydride.
The method of claim 1,

R 1 represents hydrogen or a methyl group,

Ar represents phenyl,

R 2 represents hydrogen or -XR 6 ,

Where -X- represents -O- or -OC (O)-,

R 6 is a resin mixture representing a methyl group or an ethyl group.
The method of claim 1,

The monomer of Formula 1 is a resin mixture wherein styrene is unsubstituted or substituted with one or more substituents selected from the group consisting of methyl, methoxy, ethoxy and acetoxy.
The resin mixture according to claim 1, wherein the second resin has a molecular weight distribution of 1 to 2.5.
The resin mixture according to claim 1, wherein the second resin has a weight average molecular weight of 5,000 to 200,000.
The resin mixture of claim 1, wherein the resin mixture comprises 0.1 to 50 parts by weight of the second resin based on 100 parts by weight of the first resin.
A core formed of a first resin; And a cell formed of the first resin and a second resin having a difference in surface energy, melt viscosity or solubility parameter,

The second resin,

70 to 95 parts by weight of alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms; And

Pellets which are polymers of a monomer mixture comprising 5 to 30 parts by weight of monomer of Formula 1:

[Formula 1]

Where

R 1 represents hydrogen or an alkyl group having 1 to 4 carbon atoms,

Ar represents phenyl,

R 2 represents hydrogen or -XR 6 ,

-X- represents -O- or -OC (O)-, and R <6> represents a C1-C4 alkyl group here.
Melting the resin mixture of claim 1 to form a molten mixture; And processing the melt mixture to form a layered structure.
The method for producing a resin molded article according to claim 15, wherein the step of melting and processing is performed under shear stress.
The method of manufacturing a resin molded article according to claim 15, further comprising curing the layered structure of the resin mixture.
The method for producing a resin molded article according to claim 17, wherein the curing is heat curing or UV curing.
Melting the pellets of claim 14 to form a melt mixture; And processing the melt mixture to form a layered structure.
A first resin layer; A second resin layer formed on the first resin layer; And an interfacial layer comprising a first resin and a second resin, the interfacial layer being formed between the first resin layer and the second resin layer,

The second resin is

70 to 95 parts by weight of alkyl (meth) acrylate having an alkyl group having 1 to 14 carbon atoms; And

Resin molded article which is a polymer of a monomer mixture including 5 to 30 parts by weight of the monomer of Formula 1:

[Formula 1]

Where

R 1 represents hydrogen or an alkyl group having 1 to 4 carbon atoms,

Ar represents phenyl,

R 2 represents hydrogen or -XR 6 ,

-X- represents -O- or -OC (O)-, and R <6> represents a C1-C4 alkyl group here.
The resin molded article according to claim 20, wherein the first resin layer component is detected by an infrared spectrometer on the surface of the second resin layer.
The resin molded article according to claim 20, wherein the resin molded article is a protective film for a polarizing plate.