KR102038561B1

KR102038561B1 - Impact modifier comprising nano-particle, method for preparing thereof and polylactic resin comprising the same

Info

Publication number: KR102038561B1
Application number: KR1020150066865A
Authority: KR
Inventors: 이광진; 김건수; 이창노
Original assignee: 주식회사 엘지화학
Priority date: 2015-05-13
Filing date: 2015-05-13
Publication date: 2019-10-30
Also published as: KR20160133827A

Abstract

The present invention provides an impact modifier comprising an acrylic-silicone graft copolymer and nanoparticles of a core-shell structure capable of improving impact resistance and adhesion (mold release) of a polylactic acid resin, a method for preparing the same, and a polylactic acid including the same. It relates to a resin composition and a polylactic acid resin molded article derived from the composition. Accordingly, the impact modifier can improve the transparency, impact resistance and adhesion of various resins (eg, polylactic acid resins) including the same. Therefore, the impact modifier according to the present invention and the polylactic acid resin molded article including the same may be easily applied as an industrial, particularly environmentally friendly material, which requires the same.

Description

Impact modifier comprising nanoparticles, a method of manufacturing the same and a polylactic resin comprising the same {Impact modifier comprising nano-particle, method for preparing honey and polylactic resin comprising the same}

The present invention provides an impact modifier comprising an acrylic-silicone graft copolymer and nanoparticles of a core-shell structure capable of improving impact resistance and adhesion (mold release) of a polylactic acid resin, a method for preparing the same, and a polylactic acid including the same. It relates to a resin composition and a polylactic acid resin molded article derived from the composition.

Plastic materials (PP, ABS, etc.) that use fossil resources such as petroleum and coal have excellent physical properties, but they emit carbon dioxide upon disposal, causing global warming due to the increase of carbon dioxide in the atmosphere. Therefore, in view of preventing global warming, the necessity of developing environmentally friendly materials that can reduce and replace the use of such petrochemical materials is being studied.

On the other hand, plant-derived resins produced by photosynthetic reactions using carbon dioxide and water as raw materials are incinerated, and even though carbon dioxide is generated, the generated carbon dioxide corresponds to the carbon dioxide originally present in the atmosphere, and as a result, the amount of carbon dioxide in the atmosphere is increased. I don't let you. In the case of using a carbon neutral material, the importance of the carbon neutral material is increasing in view of preventing global warming by increasing the total amount of carbon dioxide in the atmosphere.

Representative examples of such plant-derived resins include polylactic acid resins. The polylactic acid resins are obtained from corn or sugar cane and finally biodegradable (carbon neutral) into water and carbon dioxide, as well as excellent mechanical properties and Since melt molding is possible, it has been used for various purposes in various fields.

The polylactic acid resin has recently been attracting attention because it can be used in parts of automobiles or electronic products. In addition, there is a big advantage in terms of stable supply is possible because the raw material is a renewable plant that is not a petroleum resource is expected to be depleted due to limited reserves. In this regard, "biodegradable resins" are known as resins that can be degraded by the action of naturally occurring microorganisms such as bacteria and the like.

However, polylactic acid resin alone exhibits relatively hard and brittle properties as compared to other general-purpose polymer materials, and because of its low heat resistance, it is often difficult to be used in a member requiring high impact resistance and heat resistance, and adhesiveness (mold release) This is not good, there is a disadvantage that the productivity is reduced during molding. Accordingly, in order to easily apply the polylactic acid resin, a method capable of overcoming the above-mentioned disadvantages is required, and thus a method of blending a polycarbonate resin or another heterogeneous polymer into the polylactic acid resin is known.

For example, Japanese Patent Publication No. 3279768 discloses a resin composition composed of an aromatic polycarbonate / polylactic acid alloy, has a pearl luster, and has excellent impact resistance and heat resistance, but the polylactic acid resin content is limited to reduce carbon dioxide. There is a disadvantage that the effect is not great. In addition, Japanese Patent Laid-Open No. 2004-272620 has a disadvantage in that the carbon dioxide reduction effect is not large by limiting the amount of polylactic acid-based resin to 50 wt% or less in order to satisfy both heat resistance and impact resistance of the resin composition.

In the case of most of the prior art, including the above-mentioned literature, two or more kinds of polymers are blended and used, and in this case, it is often difficult to pellet the strands due to swelling during the extrusion process by separating them into respective phases. In some cases, the appearance of flow marks or surface peeling may be caused by phase separation.

Therefore, in order to use polylactic acid resin more widely and easily, there is a need for a technology capable of expressing sufficient impact strength and mold release property while using polylactic acid resin alone.

JP 3279768 B JP 2004-272620 A

The present invention has been made to solve the problems of the prior art as described above, acrylic-silicone graft copolymer and nano-particles of the core-shell structure that can improve the impact resistance and adhesion (mold release) of the polylactic acid resin An object of the present invention is to provide an impact modifier comprising a.

Another object of the present invention is to provide a method for producing the impact modifier.

Still another object of the present invention is to provide a polylactic acid resin composition comprising the impact modifier and a polylactic acid resin molded article derived from the polylactic acid resin composition.

In order to solve the above problems, the present invention is an acrylic-silicone graft copolymer of the core-shell structure; And nanoparticles, wherein the nanoparticles are aggregated on at least a portion of the graft copolymer surface.

In addition, the present invention comprises the steps of preparing a silicone-based rubber latex (step 1); Preparing an acrylic rubber latex (step 2); Preparing an acrylic-silicone rubber core latex by mixing and coagulating the prepared silicone rubber latex and acrylic rubber latex (step 3); Preparing an acrylic-silicone graft copolymer latex having a core-shell structure by grafting an acrylic shell onto the acrylic-silicone rubber core latex (step 4); And adding nanoparticles to the core-shell structured graft copolymer latex of the core-shell structure, mixing and agglomerating (step 5), wherein the nanoparticles are contained in 95 wt% to 99.5 wt% of the vinyl monomer. It provides a method for producing the impact modifier, which is a vinyl polymer prepared by adding 0.5% by weight to 5% by weight of a crosslinking agent and polymerizing.

Furthermore, the present invention is 100 parts by weight of polylactic acid resin; And 1 to 20 parts by weight of the acrylic-silicone impact modifier of the core-shell structure, and a polylactic acid resin molded article derived from the polylactic acid resin composition.

The impact modifier comprising a core-shell structured acrylic-silicone graft copolymer and nanoparticles aggregated on at least a portion of the graft copolymer according to the present invention may be formed of various resins (eg, polylactic acid resins) including the same. Transparency, impact resistance and tack can be improved.

In addition, the polylactic acid resin molded article derived from the polylactic acid resin composition including the impact modifier according to the present invention may exhibit excellent transparency, impact resistance and adhesion, and thus may be easily used without blending with other polymer resins. .

Therefore, the impact modifier according to the present invention and the polylactic acid resin molded article including the same may be easily applied as an industrial, particularly environmentally friendly material, which requires the same.

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

The terms or words used in this specification and claims are not to be construed as limiting in their usual or dictionary meanings, and the inventors may appropriately define the concept of terms in order to best describe their invention. It should be interpreted as meaning and concept corresponding to the technical idea of the present invention based on the principle that the present invention.

The present invention provides an impact modifier that can improve adhesiveness while improving the impact strength of various resins such as thermoplastic resins and polyester resins, in particular polylactic acid resins.

The impact modifier according to an embodiment of the present invention is an acrylic-silicone graft copolymer of a core-shell structure; And nanoparticles, characterized in that the nanoparticles are aggregated on at least a portion of the graft copolymer surface. Specifically, the nanoparticles may be aggregated surrounding the surface of the graft copolymer.

Here, the "aggregation" may refer to a shape in which fine particles are aggregated together, and the "aggregation" represents at least a part of the entire surface, for example, the entire surface may be divided into 10 parts. When at least one part may mean.

As described above, the impact modifier according to an embodiment of the present invention may have a form in which nanoparticles are aggregated on at least a part of the surface of the acrylic-silicone graft copolymer having a core-shell structure, and specifically, the core- Surrounding the surface of the acryl-silicon graft copolymer of the shell structure may be in the form of agglomeration of the nanoparticles. That is, the impact modifier core; A shell surrounding the core; And it may have a form of a nanoparticle aggregation layer surrounding the shell.

In addition, the nanoparticles may be included in the impact modifier 0.1 to 20 parts by weight based on 100 parts by weight of the acrylic-silicone graft copolymer of the core-shell structure.

Hereinafter, the impact modifier according to an embodiment of the present invention will be described in more detail.

Acrylic-silicone core-shell structure Graft Copolymer

The acrylic-silicone graft copolymer of the core-shell structure according to an embodiment of the present invention may be an acrylic-silicone rubber core and an acrylic shell grafted on the core surface. Specifically, the acrylic-silicone graft copolymer of the core-shell structure is 50% to 95% by weight of the acrylic-silicone rubber core; And 5 wt% to 50 wt% of the acrylic shell on the rubber core surface may be grafted. In this case, the acrylic shell may be grafted surrounding the rubber core surface.

If the acrylic-silicone-based rubber core is included in less than 50% by weight and the acrylic shell is included in an amount of more than 50% by weight, the rubber content is insufficient, the impact strength characteristics of the impact modifier may be lowered. When the acrylic-silicone-based rubber core is included in excess of 95% by weight and the acrylic shell is included in less than 5% by weight, the impact modifier containing the same, the dispersibility of the resin (eg, polylactic acid resin) is lowered to impact It may not be able to fulfill its role as an adjuvant.

The acrylic-silicone rubber core serves to impart impact strength and releasable properties to the impact modifier including the same, and may be in the form of agglomerated silicone rubber and acrylic rubber. That is, the acrylic-silicone rubber core may be in a form in which a silicone rubber and an acrylic rubber are mixed and aggregated with each other.

Specifically, the acrylic-silicone rubber core may include 0.5 wt% to 20 wt% of silicone rubber and 80 wt% to 99.5 wt% of acrylic rubber based on 100 wt% of the rubber core. More specifically, the silicone rubber and the acrylic rubber in the acrylic-silicone rubber core may have a weight ratio of 1: 4 to 20.

The silicone rubber is a polymer prepared from a cyclic siloxane monomer, and is not particularly limited, but may be prepared by a production method described below.

Specifically, the silicone rubber may include 95 wt% to 99.9 wt% of the cyclic siloxane monomer and 0.1 wt% to 5 wt% of the silane crosslinking agent based on 100 wt% of the silicone rubber.

The cyclic siloxane monomer is not particularly limited, but hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltripetylcyclotrisiloxane, tetramethyltetraphenylcyclotetra It may be one or more selected from the group consisting of siloxane and octaphenylcyclotetrasiloxane, and specifically may be octamethylcyclotetrasiloxane.

The silane-based crosslinking agent is not particularly limited, but is selected from the group consisting of tetraethoxysilane, triethoxymethylsilane, tetraethoxysilane, trimethoxymethylsilane, triethoxyphenylsilane and tetramethoxysilane. It may be abnormal.

As described above, the silicone rubber may be included in the acrylic-silicone rubber core in an amount of 0.5 wt% to 20 wt%. If the silicone rubber is included in less than 0.5% by weight, impact strength and releasability characteristics may be lowered in the impact modifier including the silicone rubber, and when the silicone rubber is included in excess of 20% by weight, the impact modifier includes the same. Problems may arise in that the transparency of the resin (eg, polylactic acid resin) manufactured using the resin is poor.

The acrylic rubber is a polymer prepared from a (meth) acrylic acid alkyl ester monomer having 2 to 8 carbon atoms, and is not particularly limited, but may be prepared by a production method described below.

Specifically, the acrylic rubber may include 97 wt% to 99.9 wt% of the (meth) acrylic acid alkyl ester monomer having 2 to 8 carbon atoms and 0.1 wt% to 3 wt% of the crosslinking agent, based on 100 wt% of the acrylic rubber.

Although the said C2-C8 (meth) acrylic-acid alkylester monomer is not specifically limited, Ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, hexyl (meth) acryl It may be one or more selected from the group consisting of a rate and 2-ethylhexyl (meth) acrylate. Specifically, it may be n-butyl acrylate.

Although the crosslinking agent is not particularly limited, specifically, aryl methacrylate, 1,3-butylene glycol dimethacrylate, 1,3-butylene glycol diacrylate, divinylbenzene, ethyleneglycol dimethacryl Latex, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, propylene glycol dimethacrylate, polyethylene glycol dimethacrylate, hexanediol dimethacrylate, trimethylol propane trimethacrylate, triethylene glycol Diacrylate, propylene glycol diacrylate, polyethylene glycol diacrylate, hexanediol diacrylate, trimethylolpropanetriacrylate, diallyl phthalate, dianthrylmaleate, divinyl adipate, triallyl cyanurate and tri At least one member selected from the group consisting of allyl isocyanate Can.

The average particle diameter of the core in the acrylic-silicone rubber core latex according to an embodiment of the present invention may be 110 nm to 250 nm. If the average particle diameter of the core is smaller than the minimum range, the average particle diameter of the final impact modifier is excessively small, and the impact strength improvement effect of the resin (eg, polylactic acid resin) manufactured using the core is insignificant. Or may not be expressed. In addition, when the average particle diameter of the core becomes larger than the above maximum range, the average particle diameter of the final impact modifier is excessively increased, and as a result, the dispersibility in the resin (for example, polylactic acid resin) is lowered and the desired effect is achieved. Can be difficult to indicate.

In this case, the average particle diameter may be measured using a capillary hydrodynamic fractionation (CHDF) after removing a small amount of solids with a 325 mesh filter by collecting a small amount of the acrylic-silicone rubber core latex sample.

The acrylic shell serves to improve the dispersibility of the impact reinforcing agent containing the thermoplastic resin, and is not particularly limited, but may be grafted around the surface of the acrylic-silicone rubber core by a manufacturing method described below. .

The acrylic shell is methyl methacrylate; And (meth) acrylic acid alkyl ester monomers having 2 to 8 carbon atoms, and specifically, 70% to 99.5% by weight methyl methacrylate and 0.5% by weight to (meth) acrylic acid alkyl ester monomers having 2 to 8 carbon atoms. And 30% by weight.

Specific examples of the (meth) acrylic acid alkyl ester monomer having 2 to 8 carbon atoms may be as described above or included.

Nanoparticles

The nanoparticles according to an embodiment of the present invention plays a secondary role of imparting impact strength and releasability to the impact modifier including the same, and are not particularly limited, but are manufactured from vinyl monomers by the following manufacturing method. It may be a system polymer.

Specifically, the nanoparticles may include 95 wt% to 99.5 wt% of the vinyl monomer and 0.5 wt% to 5 wt% of the crosslinking agent.

The vinyl monomer may be one or more selected from the group consisting of (meth) acrylic acid alkyl ester monomers, vinyl cyanated monomers and aromatic vinyl monomers.

Specifically, the (meth) acrylic acid alkyl ester monomer is not particularly limited, for example, methyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, hexyl acrylate, octyl Consisting of acrylate and 2-ethylhexyl acrylate, itel methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate and 2-ethylhexyl methacrylate It may be one or more selected from the group, the vinyl cyanated monomer may be acrylonitrile. In addition, the aromatic vinyl monomer may be one or more selected from the group consisting of styrene, α-methylstyrene, ο-methylstyrene, p-methylstyrene and p-tert-butylstyrene, 3,4-dichlorostyrene.

The crosslinking agent may be the same as or included in the crosslinking agent included in the acrylic rubber described above.

In addition, the nanoparticles may have an average particle diameter (D ₅₀ ) of 50 nm to 150 nm. In this case, the average particle diameter may be measured by the same method as the method for measuring the average particle diameter of the impact modifier described later.

As described above, the nanoparticles may be included in an amount of 0.1 parts by weight to 20 parts by weight based on 100 parts by weight of the acrylic-silicone graft copolymer having the core-shell structure. If the nanoparticles are included in an amount less than 0.1 part by weight, the impact strength and releasability characteristics may be lowered in the impact modifier including the same. can do.

The impact modifier according to an embodiment of the present invention may have an average particle diameter (D ₅₀ ) of 120 nm to 300 nm, it may be a swelling index of 2 to 10.

If the average particle diameter and the swelling index of the impact modifier are outside the above ranges, the impact resistance and transparency of the resin (eg, polylactic acid resin) using the impact modifier may not be good.

At this time, the average particle diameter can be measured by using a scanning electron microscope (SEM), the swelling index was dissolved by shaking the impact modifier 2 g in 50 ml of acetone for 48 hours, centrifuged at 20,000 rpm and 4 at -10 ℃ It may be a value obtained by running for a time sol-gel separation and calculated by the following equation (1).

[Equation 1]

In addition, the impact modifiers may be used without particular limitation as impact modifiers, such as thermoplastic resins, polyester-based resins that require an impact strength improvement, specifically, can be easily used as impact modifiers for polylactic acid resins. Can be.

In addition, the present invention provides a method for producing the impact modifier.

The manufacturing method according to an embodiment of the present invention comprises the steps of preparing a silicone-based rubber latex (step 1); Preparing an acrylic rubber latex (step 2); Preparing an acrylic-silicone rubber core latex by mixing and coagulating the prepared silicone rubber latex and acrylic rubber latex (step 3); Preparing an acrylic-silicone graft copolymer latex having a core-shell structure by grafting an acrylic shell onto the acrylic-silicone rubber core latex (step 4); And adding the nanoparticles to the acrylic-silicone graft copolymer latex having the core-shell structure, mixing and agglomerating (step 5). In this case, the nanoparticles may be a vinyl polymer prepared by adding 0.5 wt% to 5 wt% of a crosslinking agent to 95 wt% to 99.5 wt% of the vinyl monomer.

Here, the term "latex" refers to a kind of colloidal sol state in which an aqueous solution of various organic and inorganic substances is used as a dispersion medium and rubber is used as a dispersant. For example, the silicone rubber latex has a fluidity in which silicone rubber is dispersed. It may be indicative of a state.

Step 1 may be performed by adding a silane-based crosslinking agent to the cyclic siloxane monomer and polymerizing the silicone rubber latex.

For example, the silicone rubber latex may be prepared by adding 95 wt% to 99.9 wt% of the cyclic siloxane monomer and 0.1 wt% to 5 wt% of the silane-based crosslinking agent in the polymerization reactor, followed by emulsion polymerization. It is also possible to use additives.

The cyclic siloxane monomer and silane-based crosslinking agent may be as described above or included.

The emulsifier is not particularly limited, for example, alkylbenzene sulfonic acid, sodium alkylbenzene sulfonic acid, alkyl sulfonic acid, sodium alkyl sulfonate, sodium alkyl sulfosuccinate, sodium dialkyl sulfosuccinate, polyoxyethylene nonylphenyl ether sulfide Sodium carbonate, sodium alkyl sulfate, and the like, and may be used alone or in combination of two or more thereof.

The polymerization reaction may be performed for 5 hours to 24 hours in the temperature range of 30 ℃ to 100 ℃.

In addition, to stabilize the silicone rubber chain after the polymerization reaction, an alkali aqueous solution such as sodium hydroxide, potassium hydroxide, sodium carbonate, and the like may be added to neutralize and cooled to room temperature.

Step 2 may be performed by adding a crosslinking agent to a (meth) acrylic acid alkyl ester monomer having 2 to 8 carbon atoms as a step for preparing an acrylic rubber latex and polymerizing.

For example, the acrylic rubber latex may be prepared by adding 97% by weight to 99.9% by weight of a (meth) acrylic acid alkyl ester monomer having 2 to 8 carbon atoms and 0.1% by weight to 3% by weight of a crosslinking agent in an polymerization reactor. If necessary, additives such as an emulsifier and a polymerization initiator can be used.

The (meth) acrylic acid alkyl ester monomer, crosslinking agent and emulsifier having 2 to 8 carbon atoms may be the same as or included above.

Although the polymerization initiator is not particularly limited, for example, a water-soluble persulfate-based polymerization initiator such as potassium persulfate, sodium persulfate or ammonium persulfate, hydrogen peroxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, tertiary butyl hydride Redox-type polymerization initiator etc. which make peroxide, such as a loperoxide and a paramentane hydroperoxide as one component, can be added individually or in mixture.

The polymerization reaction may be performed for 5 hours to 20 hours in the temperature range of 30 ℃ to 100 ℃.

Step 3 is a step for producing an acrylic-silicone rubber core latex by agglomerating the silicone rubber latex and the acrylic rubber latex, 0.5% to 20% by weight of the silicone rubber latex and 80% to 99.5% by weight of the acrylic rubber latex It can be done by mixing and aggregating the%.

Specifically, the acrylic-silicone rubber core latex may be prepared by stirring and mixing the silicone rubber latex and the acrylic rubber latex at a weight ratio of 1: 4 to 20 based on solids, and then fine agglomerate them.

The fine agglomeration is not particularly limited, but may be carried out by adding a coagulant in a temperature range of 30 ° C. to 60 ° C., and the addition may be continuously performed for a predetermined time, or batch injection or equivalent amount may be repeated several times. It may be divided injection.

The flocculant may be an aqueous inorganic salt solution, the aqueous inorganic salt solution may be a solution of the inorganic salt diluted to 1% to 25%, the inorganic salt is not particularly limited, but may be an alkali metal salt such as sodium sulfate, sodium chloride. .

Step 4 is a step for producing a core-shell structured acrylic-silicone graft copolymer latex by graft polymerizing a monomer mixture forming an acrylic shell on the acrylic-silicone rubber core latex, the acrylic-silicone rubber The monomer mixture forming the acrylic shell may be added to the core latex and polymerized.

Specifically, 50% to 95% by weight of the acrylic-silicone rubber core latex may be performed by adding 5% to 50% by weight of a monomer mixture forming an acrylic shell and performing graft polymerization, wherein the monomer mixture is methylmetha Acrylate 70% to 99.5% by weight; And 0.5 wt% to 30 wt% of a (meth) acrylic acid alkyl ester monomer having 2 to 8 carbon atoms may be mixed. Moreover, additives, such as an emulsifier and a polymerization initiator, can be used as needed.

The (meth) acrylic acid alkyl esters and emulsifiers having 2 to 8 carbon atoms may be as described above or included.

Step 5 is a step for preparing an impact modifier in which nanoparticles are agglomerated on the surface of the acrylic-silicone graft copolymer having a core-shell structure, and the acrylic-silicone graft copolymer latex having the core-shell structure. This can be done by mixing and agglomerating the nanoparticles.

Specifically, 0.1 to 20 parts by weight of nanoparticles based on 100 parts by weight of the graft copolymer latex solid content may be added to the acrylic-silicone graft copolymer latex having the core-shell structure, mixed, and then aggregated. The nanoparticles may be added in a dispersion state by dispersing in ionized water.

In this case, the nanoparticles may be prepared by adding 0.5% by weight to 5% by weight of a crosslinking agent to 95% by weight to 99.5% by weight of a vinyl monomer, and emulsifying and polymerizing them, and additives such as an emulsifier and a polymerization initiator may be used as necessary. .

The vinyl monomer, crosslinking agent, emulsifier and polymerization initiator may be as described above or included.

The agglomeration is not particularly limited, but may be carried out by adding a coagulant at a temperature range of 30 ° C. to 60 ° C., and the coagulant is continuously added for a predetermined time, or a batch or an equivalent amount is added several times. It may be divided into the input.

The flocculant may be metal salts such as calcium chloride, magnesium chloride, magnesium sulfate, inorganic acids such as hydrochloric acid, sulfuric acid, phosphoric acid, acetic acid, organic acids, and the like, but is not limited thereto.

The manufacturing method according to an embodiment of the present invention may further include one or more steps of washing, dehydrating and drying after step 5, and the washing, dehydrating and drying are not particularly limited and are commonly known in the art. It can be carried out by the method.

In addition, the present invention provides a polylactic acid resin composition comprising an acrylic-silicone impact modifier of the core-shell structure.

The polylactic acid resin composition according to an embodiment of the present invention is 100 parts by weight of polylactic acid resin; And 1 part by weight to 20 parts by weight of the acrylic-silicon-based impact modifier of the core-shell structure.

The polylactic acid resin (PLA) according to an embodiment of the present invention generally refers to a polyester-based resin prepared through an ester reaction using lactic acid obtained by decomposing corn starch as a monomer. Commercially available products can be purchased and used.

For example, the polylactic acid resin may be one containing 95% by weight or more of L-isomer in terms of balance of heat resistance and moldability, and specifically, 95% to 100% by weight of L-isomer and 0 to 5 of D-isomer. A polylactic acid resin composed of weight% may be used. In addition, if the molding process is possible, there is no particular limitation on molecular weight or molecular weight distribution, but a weight average molecular weight of 80,000 g / mol to 300,000 g / mol may be used.

The polylactic acid resin may be a polylactic acid polymer, a polylactic acid copolymer, or a combination thereof. When the polylactic acid resin is a polylactic acid copolymer, the copolymer may be a random or random copolymerizable component with the polylactic acid polymer. Block copolymers.

In this case, the copolymerizable component may be a compound having two or more ester-bonding functional groups in a molecule, and such compounds may be prepared from dicarboxylic acids, polyhydric alcohols, hydroxycarboxylic acids other than lactic acid, lactones, and the like. Various polyester, polyether, polycarbonate, etc. are mentioned.

Examples of the dicarboxylic acid include linear or branched saturated or unsaturated aliphatic dicarboxylic acids having 4 to 50 carbon atoms, aromatic dicarboxylic acids having 8 to 20 carbon atoms, and polyether dicarboxylic acids. The aliphatic dicarboxylic acid may be succinic acid, adipic acid, sebacic acid, decane dicarboxylic acid, or the like, and the aromatic dicarboxylic acid may be phthalic acid, terephthalic acid, isophthalic acid, or the like, and the polyether dicarboxylic acid. It may be a dicarboxylic acid having a carboxy methyl group at both ends of polyalkylene ether such as polyethylene glycol, polypropylene glycol, polybutylene glycol, polyethylene polypropylene glycol and the like.

The polyhydric alcohols may include aliphatic polyols, aromatic polyhydric alcohols, polyalkylene ethers, and the like. The aliphatic polyols may include butane diol, hexane diol, octane diol, decane diol, and 1,4-cyclohexanedimer. And C2-C50 aliphatic polyols having 2 to 4 hydroxyl groups such as knol, glycerin, sorbitan, trimethylolpropane and neopentyl glycol.

The aromatic polyhydric alcohols include C2-C20 aromatic diols such as bis-hydroxy methyl benzene and hydroquinone, or bisphenols such as bisphenol A and bisphenol F, such as ethylene oxide, propylene oxide and butylene oxide. Aromatic diols which addition-reacted the alkylene oxide of 4 are mentioned.

Examples of the polyalkylene ethers include ether glycols such as ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, and polypropylene glycol.

As hydroxy carboxylic acid other than the said lactic acid, C3-C10 hydroxy carboxylic acid, such as glycolic acid, hydroxy butyl carboxylic acid, and 6-hydroxy caproic acid, is mentioned.

Examples of the lactone include glycolide, ε-caprolactone glycolide, ε-caprolactone, β-propiolactone, δ-butyrolactone, β-butyrolactone, ν-butyrolactone, and δ-valero The lactone (valerolactone) etc. are mentioned.

The polylactic acid resin composition may further include additives such as a polymer lubricant and a heat stabilizer, if necessary. The polymer lubricant and the heat stabilizer are not particularly limited and may be materials commonly known in the art.

Furthermore, the present invention provides a polylactic acid resin molded article derived from a polylactic acid resin composition containing the impact modifier.

Here, "derived from the polylactic acid resin composition" may be interpreted in the sense of being prepared from the polylactic acid resin composition, or manufactured by processing the polylactic acid resin composition. In addition, "polylactic acid molded article" may refer to any article having a specific form produced by processing the composition, or may refer to the overall polylactic acid resin prepared from the composition.

The polylactic acid resin molded article according to an embodiment of the present invention has an Izod impact strength of 10 kg · f · cm / cm ² to 30 kg · f · cm / cm ² measured according to ASTM D256 when the thickness is 3.2 mm. , Dart drop impact strength measured in accordance with ASTM D5420 may be from 30 J to 80 J.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples. However, the following Examples and Experimental Examples are provided to illustrate the present invention, and the scope of the present invention is not limited only to these examples.

Example One

1) Silicone Rubber Latex Manufacturing

Prepare a reactor of a four-necked flask equipped with a stirrer, a thermometer, a nitrogen inlet, and a purified condenser, 300 g of deionized water, 2.0 g of dodecylbenzenesulfonic acid (DBS), 98 g of octamethylcyclotetrasiloxane, and tetraethoxy 2 g of silane (TEOS) was added to the reactor, stirred for 30 minutes, and the reaction was performed for 7 hours while adjusting the temperature inside the reactor to 60 ° C. Thereafter, 0.3 g of sodium carbonate was added to the reactor and neutralized to pH 7.5. After neutralization was completed, the silicone rubber latex was prepared by cooling to room temperature for 24 hours. The prepared silicone rubber latex had a total solid contents (TSC) of 22% and an average particle diameter of 100 nm.

2) Acrylic rubber latex manufacture

A four-necked flask reactor equipped with a stirrer, a thermometer, a nitrogen inlet, and a circulation condenser was prepared, 100 g of ionized water was added thereto, and the temperature inside the reactor was raised to 65 ° C. under a nitrogen atmosphere. Separately, a monomer mixture was prepared by mixing 50 g of ionized water, 0.6 g of sodium dodecylbenzenesulfonate (SDBS), 99 g of butyl acrylate (BA), and 1 g of polyethylene glycol diacrylate (PEGDA, Mw 400 g / mol). When the internal temperature of the reactor was adjusted to 65 ° C, an acrylic rubber latex was prepared by continuously introducing and reacting the monomer mixture and 0.3 g of sodium persulfate for 6 hours in the reactor. TSC of the prepared acrylic rubber core latex was 35%, the average particle diameter was 100 m.

3) Preparation of Acrylic-Silicone Graft Copolymer Latex of Core-Shell Structure

The prepared silicone rubber latex and acrylic rubber latex were added to the reactor at a ratio of 7 g: 63 g, respectively, based on solid content, and stirred and mixed at 150 rpm for 10 minutes at room temperature. A solution of 0.4 g of sodium sulfate (Na ₂ SO ₄ ) diluted with a 10% aqueous solution was continuously added at 40 ° C. for 1 hour to prepare an acrylic-silicone rubber core latex.

20 g of ionized water and 0.15 g of sodium dodecylbenzenesulfonate (SDBS) were added to the reactor containing the prepared acrylic-silicone rubber core latex, and the temperature inside the reactor was adjusted to 60 ° C., 27 g of methyl methacrylate and butyl 3 g of acrylate and 0.1 g of sodium persulfate were continuously added for 3 hours and reacted to prepare an acrylic-silicon graft copolymer latex having a core-shell structure. The TSC of the prepared acrylic-silicon graft copolymer latex having a core-shell structure was 35%.

4) Impact modifier manufacture

First, a four-necked flask reactor equipped with a stirrer, a thermometer, a nitrogen inlet, and a circulation condenser was prepared, 150 g of ionized water was added thereto, and the temperature inside the reactor was raised to 70 ° C. under a nitrogen atmosphere. Separately, 50 g of ionized water, 2.5 g of sodium dodecylbenzenesulfonate (SDBS), 97 g of methyl methacrylate. 3 g of divinylbenzene were mixed to prepare a monomer mixture. When the temperature inside the reactor was adjusted to 70 ° C., the monomer mixture and sodium persulfate 1.5 were continuously added for 5 hours and reacted to prepare nanoparticles. The average particle diameter of the produced nanoparticles was 70 nm.

To 100 g of the acrylic-silicone graft copolymer latex solid content of the core-shell structure prepared above, a solution obtained by diluting the nanoparticles 5 g in 20% in ionized water was added thereto, and 4 g of calcium chloride was added at 40 ° C. to aggregate them. Washing and drying to prepare an impact modifier powder.

Example 2

An impact modifier powder was prepared in the same manner as in Example 1, except that 1 g of nanoparticles were used to prepare the impact modifier of Example 1-4.

Example 3

The impact modifier powder was prepared in the same manner as in Example 1, except that 15 g of the nanoparticles were used to prepare the impact modifier of Example 1-4.

Example 4

In preparing the acrylic-silicone rubber core latex of Example 1-3), the silicone rubber latex and the acrylic rubber latex are used at a solid content of 6 g: 54 g, 36 g of methyl methacrylate, and 4 g of butyl acrylate. Except that it was used in the same manner as in Example 1 was prepared in the impact modifier powder.

Example 5

In preparing the acrylic-silicone rubber core latex of Example 1-3), the silicone rubber latex and the acrylic rubber latex are used at a solid content of 8 g: 72 g, 18 g of methyl methacrylate and 2 g of butyl acrylate. Except that it was used in the same manner as in Example 1 was prepared in the impact modifier powder.

Example 6

The impact modifier powder was prepared in the same manner as in Example 1, except that the silicone rubber latex and the acrylic rubber latex were used at 3.5 g: 66.5 g based on solids when preparing the acrylic-silicone rubber core latex of Example 1-3). Was prepared.

Example 7

The impact modifier powder was prepared in the same manner as in Example 1, except that silicone rubber latex and acrylic rubber latex were used at a solid content of 10.5 g: 59.5 g based on the solid content of the acrylic-silicone rubber core latex of Example 1-3). Was prepared.

Example 8

An impact modifier powder was prepared in the same manner as in Example 1, except that 0.2 g of sodium persulfate was used in preparing the acrylic-silicone rubber core latex of Example 1-3).

Example 9

An impact modifier powder was prepared in the same manner as in Example 1, except that 0.8 g of sodium persulfate was used at a temperature of 55 ° C. in preparing the acrylic-silicone rubber core latex of Example 1-3).

Example 10

In preparing the silicone rubber latex of Example 1-1), butyl acrylate was used in preparing the acrylic rubber latex of Example 1-2) using 96 g of octamethylcyclotetrasiloxane and 4 g of tetraethoxysilane. Was prepared in the same manner as in Example 1, except that 98 g of polyethylene glycol diacrylate was used in 2 g.

Example 11

99 g of octamethylcyclotetrasiloxane and 1 g of tetraethoxysilane were used to prepare the silicone rubber latex of Example 1-1), and butyl acrylate was used to prepare the acrylic rubber latex of Example 1-2). Was prepared in the same manner as in Example 1, except that 99.6 g of polyethylene glycol diacrylate was used as 0.4 g.

Example 12

An impact modifier was prepared in the same manner as in Example 1, except that decamethylcyclopentasiloxane was used instead of octamethylcyclotetrasiloxane when preparing the silicone rubber latex of Example 1-1.

Example 13

An impact modifier was prepared in the same manner as in Example 1, except that triethoxymethylsilane was used instead of tetraethoxysilane when preparing the silicone rubber latex of Example 1-1.

Comparative example One

An impact modifier was prepared in the same manner as in Example 1, except that nanoparticles were not used to prepare the impact modifier of Example 1-4.

Comparative example 2

An impact modifier was prepared in the same manner as in Example 1, except that 25 g of the nanoparticles was used to prepare the impact modifier of Example 1-4.

Comparative example 3

When preparing the acrylic-silicone rubber core latex in Example 1-3), the silicone rubber latex and the acrylic rubber latex are used based on a solid content of 10 g: 90 g, and then methyl methacrylate and butyl acrylate are added to graft. An impact modifier was prepared in the same manner as in Example 1 except that the step of forming the shell was not performed. That is, the nanoparticles were added to the acrylic-silicone rubber core latex and coagulated to prepare an impact modifier.

Comparative example 4

When preparing the acrylic-silicone rubber core latex in Example 1-3), using the silicone crab rubber latex and the acrylic rubber latex at a solid content of 4 g: 36 g, the acrylic-silicone graft copolymer of the core-shell structure An impact modifier was prepared in the same manner as in Example 1 except that 54 g of methyl methacrylate and 6 g of butyl acrylate were used to prepare the latex.

Comparative example 5

The impact modifier was prepared in the same manner as in Example 1, except that the silicone rubber latex was not used to prepare the acrylic-silicone rubber core latex in Example 1-3).

Comparative example 6

The impact modifiers were prepared in the same manner as in Example 1, except that silicone rubber latex and acrylic rubber latex were used at a solid content of 21 g: 49 g when preparing the acrylic-silicone rubber core latex in Examples 1-3). Prepared.

Comparative example 7

The impact modifier was prepared in the same manner as in Example 1, except that the step of adding sodium sulfate after mixing and mixing the silicone rubber latex and the acrylic rubber latex in Example 1-3).

Comparative example 8

An impact modifier was prepared in the same manner as in Example 1, except that 100 g of octamethylcyclotetrasiloxane was used instead of tetraethoxysilane to prepare the silicone rubber latex of Example 1-1.

Comparative example 9

An impact modifier was prepared in the same manner as in Example 1 except that 92 g of octamethylcyclotetrasiloxane and 8 g of tetraethoxysilane were used to prepare the silicone rubber latex of Example 1-1. .

Comparative example 10

Silicone rubber latex and acrylic rubber latex were prepared according to Examples 1-1) and 1-2), respectively.

The prepared silicone rubber latex and acrylic rubber latex were added to the reactor at a ratio of 7 g: 63 g, respectively, based on solid content, and stirred and mixed at 150 rpm for 10 minutes at room temperature. A solution of 0.4 g of sodium sulfate (Na ₂ SO ₄ ) diluted with a 10% aqueous solution was continuously added at 40 ° C. for 1 hour to prepare an acrylic-silicone rubber core latex. The average particle diameter of the rubber in the prepared acrylic-silicone rubber core latex was 180 nm.

5 g of nanoparticles were added to the reactor containing the prepared acrylic-silicone rubber core latex and 0.5 g of sodium sulfate (Na ₂ SO ₄ ) was diluted in a 10% aqueous solution. Hypertrophy was performed. At this time, the content of the nanoparticles is shown based on 100g of the acrylic-silicone rubber core latex solids.

Thereafter, 20 g of ionized water and 0.15 g of sodium dodecylbenzenesulfonate (SDBS) were added thereto, and the temperature inside the reactor was adjusted to 60 ° C., followed by 27 g of methyl methacrylate, 3 g of butyl acrylate, and 0.1 g of sodium persulfate. Continuous injection and reaction for 3 hours to prepare a core-shell structured acrylic-silicon graft copolymer latex. The TSC of the prepared acrylic-silicon graft copolymer latex having a core-shell structure was 35%.

4 g of calcium chloride was added to the prepared core-shell structured acrylic-silicon graft copolymer latex and coagulated, followed by washing with water and drying to prepare an impact modifier powder.

Experimental Example One

In order to compare the physical properties of each of the impact modifiers prepared in Examples 1 to 13 and Comparative Examples 1 to 10, the average particle diameter and the swelling index were measured. The results are shown in Tables 1 to 3 below.

The average particle diameter was measured using a capillary hydrodynamic fractionation (CHDF) after removing a small amount of solids with a 325 mesh filter in the case of latex samples in the case of latex, SEM (scanning electron microscope) ) Was measured.

The swelling index was melted by shaking a shaker for 2 hours in 50 ml of acetone powder 50 ml of acetone, and centrifuged at 20,000 rpm, and then operated at -10 ° C. for 4 hours to perform sol-gel separation. Calculated and obtained.

[Equation 1]

Experimental Example 2

In order to compare the adhesiveness, impact resistance and transparency of the polylactic acid resin prepared by using the impact modifiers prepared in Examples 1 to 13 and Comparative Examples 1 to 10, a polylactic acid resin composition including each impact modifier was prepared. The mold release test, impact strength test, and Haze measurement were performed using the same. The results are shown in Tables 1 to 3 below.

First, 100 parts by weight of polylactic acid resin (2002D, Cargill Dow), 10 parts by weight of each impact modifier powder prepared in Examples 1 to 13 and Comparative Examples 1 to 10, polymer lubricant (AC316, Hoeywell, USA) ) 0.5 parts by weight and 0.2 parts by weight of heat stabilizer (IR-1076, Ciba, Switzerland) were melt mixed for 10 minutes at 190 ° C and 30 rpm using a Haake Rheomix 600 Batch mixer to prepare a polylactic acid resin composition. Water was sufficiently removed before manufacture.

1) Mold release ability test

In order to compare and analyze the adhesiveness, it was evaluated by the five-point method according to the adhesion degree of each polylactic acid resin composition prepared in the chamber.

2) impact strength test

In order to compare the impact resistance, each polylactic acid resin composition prepared above was compressed to 0.2 MPa at 200 ° C. for 10 minutes using a compression mold to prepare a specimen having a thickness of 3.2 mm. The Izod impact test was made with a notch depth of 2.54 mm, measured at room temperature according to ASTM D256, and the falling dart impact test was measured according to ASTM D5420.

3) Haze measurement

In order to compare the transparency, each polylactic acid resin composition prepared above was compressed to 0.2 MPa for 10 minutes at 200 ° C. using a compression mold to prepare specimens having a thickness of 1/8 inch. Each specimen was measured according to ASTM D1003 using a Haze meter.

division Example Comparative example One 2 3 12 13 One 2 10 Average particle diameter of the core (nm) 180 180 180 177 179 180 180 185 Impact modifier Average particle size (nm) 200 200 200 197 203 200 200 205 Swelling index 5.5 5.5 5.5 6.0 6.5 5.5 5.5 3.5 Haze (5.0 or less) 2.9 2.8 3.9 3.0 3.1 2.5 8.5 6.5 Mold Release (4 or more) 5 4 5 5 5 One 4 One Izod impact strength (kg · f · cm / cm ² , 7 or more) 16 17 18 17 20 2 4 3 Dart drop impact strength (J, 30 or more) 50 52 53 52 55 12 24 20 Mold release: 5 points (very good), 4 points (good), 3 points (normal), 2 points (bad), 1 point (very bad)

Table 1 shows the results of analyzing the adhesion (mold release), impact resistance and transparency (Haze) change according to the inclusion and content ratio of the nanoparticles in the impact modifier.

As shown in Table 1, the polylactic acid resin molded article manufactured using the impact modifiers prepared in Examples 1 to 3, 12, and 13 according to an embodiment of the present invention is Comparative Examples 1 to Compared with the polylactic acid resin molded article prepared using the impact modifier prepared in 2 and Comparative Example 10, it was confirmed that the overall excellent adhesion, impact resistance and transparency.

Specifically, Examples prepared by using the nanoparticles according to an embodiment of the present invention using 1 part by weight, 5 parts by weight and 15 parts by weight based on 100 parts by weight of the acrylic-silicone graft copolymer latex solid of the core-shell structure In the case of the polylactic resin molded article including the impact modifiers of Examples 1 and 2, the Haze characteristics (transparency), mold release property (adhesiveness), and Izod impact strength and dart drop impact strength characteristics (impact resistance) are all high. The figures are shown. However, the polylactic acid resin including the impact modifier of Comparative Example 1, in which the nanoparticles are not used, has a mold release property, an Izod impact strength characteristic, and a dart drop impact strength characteristic. The polylactic acid resin molded article containing the impact modifier of Comparative Example 2, which was significantly lower than the lactic acid resin molded article and was used at 25 parts by weight in excess of 20 parts by weight, which is nanoparticles, was used in the Haze properties and Izod. Impact strength characteristics and dart drop impact strength characteristics were significantly reduced compared with the polylactic acid resin molded article containing the impact modifiers of Examples 1 to 3.

As a result of the above, the impact modifier according to an embodiment of the present invention comprises nanoparticles as one component, thereby further improving the impact strength characteristics and mold release properties (adhesiveness) of the polylactic acid resin molded article manufactured using the impact modifier. In particular, in the case of including the nanoparticles in a specific content range, it was confirmed that the Haze property can be improved while improving the impact strength property and mold release property (adhesiveness).

In addition, in the case of the impact modifiers prepared in Comparative Example 10, the nanoparticles were used within the appropriate range proposed in the present invention, but all the physical properties measured in comparison with the impact modifiers of Examples 1 to 3 and Examples 12 and 13 It showed a significantly lower value in. This is a result that means that the aggregation position of the nanoparticles may be an important factor in order to achieve the desired physical properties.

division Example Comparative example 4 5 6 7 3 4 5 6 Average particle diameter of the core (nm) 182 184 181 179 177 175 180 179 Impact modifier Average particle size (nm) 205 210 206 204 203 202 201 197 Swelling index 6.5 4.8 5.4 5.3 5.4 7.2 5.7 5.6 Haze (5.0 or less) 2.6 3.3 2.7 3.7 6.1 3.2 5.5 8.2 Mold Release (4 or more) 4 5 4 5 3 One One 3 Izod impact strength (kg · f · cm / cm ² , 7 or more) 14 18 13 20 3 3 4 6 Dart drop impact strength (J, 30 or more) 45 55 44 59 17 20 16 28 Mold release: 5 points (very good), 4 points (good), 3 points (normal), 2 points (bad), 1 point (very bad)

Table 2 shows the results of analyzing the mechanical and chemical property changes according to the ratio of the core and the shell in the acrylic-silicone graft copolymer of the core-shell structure included in the impact modifier and the ratio of the acrylic rubber and the silicone rubber in the core. It is shown.

As shown in Table 2, the polylactic acid resin molded article manufactured using each of the impact modifiers prepared in Examples 4 to 7 according to an embodiment of the present invention is each impact modifier of Comparative Examples 3 to 6 Compared to the polylactic acid resin molded article manufactured using the Haze characteristics (transparency), mold release properties (adhesiveness) and Izod impact strength and dart drop impact strength characteristics (impact resistance) was confirmed to be excellent overall.

Specifically, using the impact modifiers of Examples 4 and 5, Comparative Examples 3 and 4 prepared by controlling the ratio of the core and the shell in the acrylic-silicone graft copolymer of the core-shell structure differently Comparing the manufactured polylactic acid resin molded article, the ratio of the polylactic acid resin molded article manufactured using the impact modifier of Comparative Example 3 in which the shell is not formed and the shell is excessively high (60 wt based on 100 wt% of the graft copolymer). %) The polylactic acid resin molded article prepared by using the impact modifier of Comparative Example 4 exhibited significantly lower mold release properties (adhesiveness) and both Izod impact strength and dart drop impact strength characteristics (impact resistance).

In addition, the ratio of the core and the shell is the same, but using the impact modifiers of Examples 5 and 6 and Comparative Examples 5 and 6 prepared by differently adjusting the ratio of the acrylic rubber and silicone rubber contained in the core When comparing the manufactured polylactic acid resin molded article, the ratio of the polylactic acid resin molded article manufactured using the impact modifier of Comparative Example 5 including an acrylic rubber core not containing silicone rubber and the silicone rubber was excessively high (core 100 wt. The polylactic acid resin molded article manufactured using the impact modifier of Comparative Example 6 containing a core based on 30% by weight) had Haze characteristics (transparency), mold release properties (tackiness), and Izod impact strength and dart drop impact strength characteristics (impact resistance). ) All showed significantly lower values.

This is because Haze properties (transparency), mold release property (adhesiveness) and Izod are excellent in the ratio of the core and the shell in the acrylic-silicone graft copolymer of the core-shell structure included in the impact modifier and the ratio of the acrylic rubber and the silicone rubber in the core. The results indicate that the impact strength and dart drop impact strength characteristics (impact resistance) may be an important factor in expressing the characteristics.

division Example Comparative example 8 9 10 11 7 8 9 Average particle diameter of the core (nm) 130 250 183 182 100 178 180 Impact modifier Average particle size (nm) 145 273 195 206 112 203 205 Swelling index 5.7 5.3 3.6 7.5 5.6 11.0 1.7 Haze (5.0 or less) 2.6 3.4 2.3 3.5 8.0 7 5.1 Mold Release (4 or more) 5 4 4 4 One 2 One Izod impact strength (kg · f · cm / cm ² , 7 or more) 15 19 12 21 2 3 2 Dart drop impact strength (J, 30 or more) 48 54 41 63 15 16 13 Mold release: 5 points (very good), 4 points (good), 3 points (normal), 2 points (bad), 1 point (very bad)

Table 3 shows the results of analyzing the mechanical and chemical properties according to the average particle diameter and swelling index of the impact modifier. Here, the average particle diameter of the impact modifier was adjusted according to the agglomeration conditions in the production of acrylic-silicone rubber core latex, the swelling index was adjusted by the content of the silane-based crosslinking agent in the production of silicone rubber latex.

As shown in Table 3, the polylactic acid resin molded article manufactured using each of the impact modifiers prepared in Examples 8 to 11 according to an embodiment of the present invention is each impact modifier of Comparative Examples 7 to 9 Compared to the polylactic acid resin molded article manufactured using the Haze characteristics (transparency), mold release properties (adhesiveness) and Izod impact strength and dart drop impact strength characteristics (impact resistance) was confirmed to be excellent overall.

Specifically, the polylactic acid resin molded article manufactured using the impact modifier of Comparative Example 7 having an average particle diameter of less than 120 nm, the impact modifier of Comparative Example 8 (11.7) and Comparative Example 9 (1.7) outside the swelling index 2 to 10 range The polylactic acid resin molded article manufactured by using the resin has significantly lowered Haze properties, mold release properties and Izod impact strength and dart drop impact compared to the polylactic acid resin molded article prepared using the impact modifiers prepared in Examples 8 to 11. Strength characteristics (impact resistance) are shown.

This result indicates that the average particle diameter and swelling index of the impact modifier may be important factors for developing excellent Haze characteristics (transparency), mold release property (adhesiveness), and Izod impact strength and dart drop impact strength characteristics (impact resistance). .

Here, the average particle diameter of the impact modifier was adjusted according to the agglomeration of the acrylic-silicone rubber core latex production, the swelling index was adjusted to the content of the silane-based crosslinking agent in the production of silicone rubber latex.

Claims

An acrylic-silicone graft copolymer having a core-shell structure; And nanoparticles,
The nanoparticles are aggregated on at least a part of the surface of the acrylic-silicone graft copolymer,
The nanoparticles are included in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the acrylic-silicone graft copolymer,
An impact modifier having an average particle diameter (D ₅₀ ) of 120 nm to 300 nm and a swelling index of 2 to 10.

delete

The method according to claim 1,
The nanoparticles are impact modifiers that are aggregated surrounding the surface of the graft copolymer.

The method according to claim 1,
The nanoparticle is a vinyl polymer,
The vinyl polymer is an impact modifier comprising 95% to 99.5% by weight of the vinyl monomer and 0.5% to 5% by weight of the crosslinking agent.

The method according to claim 4,
The vinyl monomer is an impact modifier of at least one selected from the group consisting of (meth) acrylic acid alkyl ester monomers, vinyl cyanated monomers and aromatic vinyl monomers.

The method according to claim 5,
The (meth) acrylic acid alkyl ester monomers include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, Impact modifiers selected from the group consisting of ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate and 2-ethylhexyl methacrylate .

The method according to claim 5,
The vinyl cyanide monomer is an impact modifier that is acrylonitrile.

The method according to claim 5,
The aromatic vinyl monomer is an impact modifier of at least one selected from the group consisting of styrene, α-methylstyrene, ο-methylstyrene, p-methylstyrene and p-tert-butylstyrene, 3,4-dichlorostyrene.

The method according to claim 4,
The crosslinking agent is aryl methacrylate, 1,3-butylene glycol dimethacrylate, 1,3-butylene glycol diacrylate, divinylbenzene, ethylene glycolo dimethacrylate, diethylene glycol dimethacrylate , Triethylene glycol dimethacrylate, propylene glycol dimethacrylate, polyethylene glycol dimethacrylate, hexanediol dimethacrylate, trimethylol propane trimethacrylate, triethylene glycol diacrylate, propylene glycol diacrylate , Polyethylene glycol diacrylate, hexanediol diacrylate, trimethylolpropanetriacrylate, diallyl phthalate, dianlymaleate, divinyl adipate, triallyl cyanurate and triallyl isocyanate Impact reinforcement that is more than.

The method according to claim 1,
The nanoparticles are impact modifiers having an average particle diameter (D ₅₀ ) of 50 nm to 150 nm.

The method according to claim 1,
The graft copolymer is 50% to 95% by weight of the acrylic-silicone rubber core; And 5 wt% to 50 wt% of an acrylic shell,
And said shell is graft polymerized surrounding said rubber core surface.

The method according to claim 11,
The acrylic-silicone rubber core is an impact modifier in which a silicone rubber and an acrylic rubber are agglomerated with each other.

The method according to claim 11,
The acrylic silicone rubber core is an impact modifier comprising 0.5 to 20% by weight of the silicone rubber and 80 to 99.5% by weight of the acrylic rubber.

The method according to claim 11,
The acrylic silicone rubber core is an impact modifier comprising a silicone rubber and an acrylic rubber in a weight ratio of 1: 4 to 20.

The method according to claim 11,
The acrylic shell is 70% to 99.5% by weight of methyl methacrylate; And 0.5 wt% to 30 wt% of a (meth) acrylic acid alkyl ester monomer having 2 to 8 carbon atoms.

delete

The method according to claim 1,
The impact modifier is an impact modifier that is an impact modifier for polylactic acid resin.

1) preparing a silicone rubber latex;
2) preparing an acrylic rubber latex;
3) preparing an acrylic-silicone rubber core latex by mixing and coagulating the prepared silicone rubber latex and acrylic rubber latex;
4) preparing an acrylic-silicone graft copolymer latex having a core-shell structure by grafting an acrylic shell on the acrylic-silicone rubber core latex; And
5) adding and mixing the nanoparticles to the graft copolymer latex and then agglomerating;
The nanoparticle is a vinyl polymer prepared by adding 0.5% by weight to 5% by weight of a crosslinking agent to 95% by weight to 99.5% by weight of a vinyl monomer and polymerizing the impact modifier according to claim 1.

The method according to claim 19,
The silicone rubber latex is prepared by adding 0.1 to 5 wt% of a silane crosslinking agent to 95 to 99.9 wt% of a cyclic siloxane monomer and polymerizing it.

The method of claim 20,
The cyclic siloxane monomers include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, trimethyltripetylcyclotrisiloxane, tetramethyltetraphenylcyclotetrasiloxane and octaphenylcyclotetra Method for producing an impact modifier that is one or more selected from the group consisting of siloxanes.

The method of claim 20,
The silane-based crosslinking agent is at least one selected from the group consisting of tetraethoxysilane, triethoxymethylsilane, tetraethoxysilane, trimethoxymethylsilane, triethoxyphenylsilane and tetramethoxysilane. Manufacturing method.

The method according to claim 19,
The acrylic rubber latex is prepared by adding 0.1% to 3% by weight of a crosslinking agent to 97% by weight to 99.9% by weight of a (meth) acrylic acid alkyl ester monomer having 2 to 8 carbon atoms and polymerizing it.

The method according to claim 19,
The acrylic silicone rubber core latex of step 3) is prepared by mixing and agglomerating 0.5 wt% to 20 wt% of silicone rubber latex and 80 wt% to 99.5 wt% of acrylic rubber latex.

The method according to claim 19,
The acrylic-silicone graft copolymer latex of the core-shell structure of step 4) is added to 50% to 95% by weight of the acrylic-silicone rubber core latex to add 5% to 50% by weight of the monomer mixture forming the acrylic shell. Prepared by graft polymerization,
The monomer mixture comprises 70% to 99.5% by weight of methyl methacrylate; And 0.5 wt% to 30 wt% of a (meth) acrylic acid alkyl ester monomer having 2 to 8 carbon atoms is mixed.

The method according to claim 19,
The nanoparticles of step 5) is a method of producing an impact modifier of 0.1 to 20 parts by weight based on 100 parts by weight of the acrylic-silicone graft copolymer latex solid of the core-shell structure.

100 parts by weight of polylactic acid resin; And
Poly-lactic acid resin composition comprising 1 to 20 parts by weight of the acrylic-silicon-based impact modifier of the core-shell structure of claim 1.

The polylactic acid resin molded article derived from the polylactic acid resin composition of Claim 27.

The method according to claim 28,
The molded article has an Izod impact strength of 10 kg · f · cm / cm ² to 30 kg · f · cm / cm ² measured according to ASTM D256 when the thickness of the molded article is 3.2 mm, and the dart drop impact strength measured according to ASTM D5420. Is 30 J to 80 J polylactic acid resin molded article.