JPS62236850A - Polycarbonate resin composition - Google Patents

Abstract

PURPOSE:To provide a dried core/shell type emulsion-polymerized particle which is suitable for use as a filler for improving the moldability and impact resistance of polycarbonate resins, by forming the core part by using a thermoplastic resin having a glass transition point higher than that of the shell part. CONSTITUTION:A polymerizable vinyl monomer is emulsified by using an emulsifier and seed latex particles are then formed by using a redox catalyst. A monomer capable of forming a thermoplastic resin having a high glass transition point (e.g., styrene) is fed an polymerized in the presence of an oil-soluble radical generating agent to produce a core part. A monomer capable of forming a thermoplastic resin which has a relatively low glass transition point and is highly hydrophilic (e.g., butyl acrylate) is fed and polymerized to produce a shell part. The resulting core/shell type emulsion-polymerized particles are separated and dried. When the dried particles are dispersed in a polycarbonate resin, the impact resistance, etc., can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to dried products of core-shell type emulsion polymer particles composed of thermoplastic resins, and The present invention relates to a polycarbonate resin composition containing a polycarbonate resin having excellent moldability.

Polycarbonate resin has excellent mechanical properties such as impact resistance, so it is often used as an engineering plastic for industrial parts such as electrical parts, as well as miscellaneous goods for iJi FL. has been done. However, the disadvantage of polycarbonate (41 fingers) is that it has a higher melt viscosity than other thermoplastic resins and requires a higher molding temperature during the molding process. Many proposals have been made, and some of them are actually put into practical use.

For example, by blending a polyolefin such as polyethylene or an ABS resin with a polycarbonate resin, it is possible to improve its moldability and impact resistance. However, it is said that such blends (J1 tensile yield strength, tensile modulus, and even heat resistance tend to decrease.
A method of blending S resin and borisdyrene has also been proposed, but such blends tend to have lower impact resistance.

The inventors of the present invention have developed particles from a thermoplastic resin latex with a special core-shell structure manufactured using emulsion polymerization technology, which is known per se. The particles were separated while maintaining their shape and a dried product was obtained. In this case, the core part is made up of a resin component that has a glass transition point above room temperature, and the shell part is made up of a resin component that has a glass transition point lower than that of the core part. By melt-blending the dried material (J) with a polycarbonate resin, it can be dispersed extremely finely in the resin, and (2) a polycarbonate resin composition in which the fine particles are uniformly dispersed. The product is made without any loss of the excellent mechanical properties inherent to polycarbonate resin.
It has been found that moldability and impact resistance are significantly improved. The present invention was completed based on this knowledge.

That is, the present invention provides (1) a dried core-shell type emulsion polymer particle in which the core part is composed of a thermoplastic resin having a higher glass transition point than the nonyl part, and (2) a polycarbonate comprising the dried product. It is a resin composition.

The core nonyl type emulsion polymer particles as used in the present invention refer to latex particles having a core part and a shell part obtained by an emulsion polymerization method. It is not necessary that the resin layer constituting the core part and the resin layer constituting the shell part be separated by a clear boundary surface, but usually the resin composition is continuous. The core part contains 4 fake J filter resin (J1 glass transition point or above room temperature - 1-1 preferably 6
It is composed of rays above 0°C. In addition, the resin in the shell part (Jl) is made of a material whose glass transition point is lower than the glass transition point of the resin constituting the core part by at least 20°C, preferably by at least 50°C, and is highly hydrophilic. do.

Note that the glass transition point is a value measured with a differential calorimeter (DSC).

Such core-shell type emulsion polymer particles can be produced by the following method.

(A) Manufacturing method of core-shell type emulsion polymerization particles Basically, they can be manufactured using conventional emulsion polymerization technology, but in order to make core-shell type particles, an oil-soluble radical generator is required. A polymerization method using the following three steps can be mentioned.

(1) First, a vinyl polymerizable monomer is emulsified with an emulsifier, and seed latex particles are generated using a redox catalyst. At this time, an oil-soluble radical generator is present in the seed latex particles.

(2) Next, a vinyl polymerizable monomer that provides a resin composition with a high glass transition point is supplied and polymerized to produce a core portion.

(2) Furthermore, a vinyl polymerizable monomer having a relatively low glass transition point and a highly hydrophilic resin component is supplied and polymerized to produce the shell part.

Examples of emulsifiers include anionic emulsifiers such as alkyl aromatic sulfonates (such as sodium dodecylbenzenesulfonate) and sulfuric acid ester salts (such as sodium lauryl sulfate), and emulsifiers such as polyoxyethylene nonylphenyl ether and polyoxyethylene lauryl ether. Nonionic emulsifiers can be used. In the case of anionic emulsifier, it is 0.1 to 2% by weight based on the vinyl polymerizable monomer.

In the case of a nonionic emulsifier, it is used in an amount of 1 to 4% by weight based on the monomer. Examples of the oil-soluble radical generator include penzoyl peroxide and azobisisobutyronitrile. Emulsion polymerization CJ1 is usually carried out at a temperature of 50 to 900C.

In the polymerization step (1), the amount of emulsifier used is preferably controlled to the minimum necessary level in order to prevent the generation of new particles. It is preferable to continuously supply the emulsifier and monomer to the reaction solution using a regular pump or a dropping funnel. At this time, by preparing an emulsion by pre-emulsifying the monomer with an emulsifier and deionized water and supplying this emulsion, the amount of emulsifier used can be reduced, and particles that do not have a core-shell type can be produced. It is possible to prevent 11-. In addition, even if the order of "■ and ■" is reversed, core-shell type polymer particles will be produced, but in this case, the glass transition point will be relatively high, since the particles will be produced later.
A resin with low hydrophilicity will be embedded as a core portion.

Vinyl polymerizable monomers that can be used to produce core-shell particles in the present invention include, for example, aromatic vinyl monomers such as styrene and vinyltoluene; halogenated vinyl monomers such as vinyl chloride and vinylidene chloride; For example, dilyl monomers such as acrylonitrile and methacrylic[nonitrile; methacrylic acid esters such as medyl methacrylate, butyl methacrylate, and hydroxyedyl methacrylate; such as methyl acrylate, edyl acrylate, butyl acrylate, and acrylic acid. Acrylic acid esters such as 2-ethyl/ginol, hydroxyethyl acrylate, vinyl esters such as vinyl acetate and vinyl propionate, such as acrylamide.

Mention may be made of unsaturated amides such as methacrylamide, unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, maleic acid and fumaric acid. Furthermore, a conjugated diene such as butadiene or isoprene may be added to these vinyl polymerizable monomers for copolymerization.

Among the pinyl polymerizable monomers described in -1-, preferred monomers for forming the resin of the core part include styrene, acrylonitrile, methyl methacrylate, etc., and nonylene for forming the resin of the nonyl part. Preferred monomers include ethyl acrylate, butyl acrylate, butyl methacrylate, etc. Also, monomers that lower the glass transition point of the resin,
For example, 2-edylheginyl acrylate, butanene,
Isoprene or the like may be copolymerized. Further, as the resin constituting the shell portion, a hydrophilic resin is particularly preferable, and in order to produce such a resin, for example, acrylic acid, methacrylic acid, and acrylamide are used.

A monomer having a hydrophilic functional group such as hydroxyethyl acrylate may be copolymerized.

By the above emulsion polymerization method, the particle size is usually 1100n~50nm.
An emulsion with latex particles of 0 nm is obtained.

(B) Core-shell type emulsion polymerization liquid (J, Mar') Yon)
Manufacture of dried products from - Noko latex particles obtained by emulsion polymerization -7
= can be separated while maintaining the particle form using conventional means such as salting out, freeze-thaw, or spray drying. If the glass transition point of the resin in the shell part is below room temperature, freezing and thawing is preferable. After that, it can be separated into a powdered or crushed dried product.For salting out, an electrolyte solution such as calcium chloride or sodium chloride is used for salting out, and the precipitate is filtered out and washed with water and dried. Air blow dryer or vacuum dryer (room temperature ~
60° C. for 4 to 6 hours) or infrared drying. Grinding should be done using a hammer mill or the like.

By blending the thus obtained dried core-shell type emulsion polymer particles with a polycarbonate resin, a polycarbonate resin composition containing the dried particles can be obtained.

Examples of the polycarbonate resin that can be used in the present invention include bis(hydroxy aromatic) alkane-based polycarbonate resins.

Specifically, for example, bis(4-hydrogynephenyl)
Methane, his(4-hydroxyphenyl)ethane, 2.
His(hydroxyphenyl)alkanes such as 2'-bis(4-human[1gysyphenyl)propane or 2,2'-bis(4-hydroxy-3°5-dichlorophenyl)propane and phosgene or diphenyl] Resins obtained by reaction with enyl carbonate-1 can be used, and these resins may be used alone or in combination of two or more types.

A method for obtaining a resin composition by blending both components is as follows:
There are a melt blending method and a triblending method, and either one may be used.

Melt blending is usually carried out at a temperature of about 220 DEG to 270 DEG C. using heated rolls, a pan rimigizer, or a single-screw or multi-screw extruder. The blend may be in any form, such as pellets or granules. In addition, in the case of tri-blend, both ingredients are powdered in 1. Alternatively, a method such as mixing both components and then applying a high-speed mixer to a powder composition may be adopted.

Polycarbonate I/resin vs. Zuro core/nonyl Ql, 1
The blending ratio of the dry emulsion polymer particles is usually 40 to 99% by weight of the polycarbonate resin component, preferably 1 or 60 to 9%.
5-fold nail % and dry matter 60~] 5-layer nail %, preferably 40~
The proportion is 5% by weight. If the proportion of the polycarbonate resin component is less than 40% by weight, the dried material will not become dispersed particles but will become a continuous phase, and if it exceeds 99% by weight, no blending effect will be achieved, making it impossible to achieve the object of the present invention.

In addition to the above-mentioned components, the composition of the present invention may also contain a flame retardant, a mold release agent, a weather resistance imparting agent, an antioxidant 11-agent, an antistatic 11] agent, and a heat-resistant agent, depending on the intended use. Conventional auxiliary ingredients such as additives, colorants, reinforcing agents, surfactants, inorganic fillers, lubricants, etc. can be added.

As a method for manufacturing a molded article using the composition of the present invention, conventional molding means such as injection molding and extrusion molding can be employed. Molding is usually carried out under heating conditions of 220 to 300°C.

glIJl-9-type 7-% Polycarbonate resin composition of the present invention (") has good fluidity during molding and is extremely easy to mold.1.
In addition, the molded article t-1 obtained from the resin composition has excellent mechanical properties such as impact resistance and tensile strength. The 17 types listed below (1-) also showed high impact resistance i1
It has the advantage of... In addition, it has the characteristic that it does not suffer from a decrease in R mechanical properties, such as a decrease in heat resistance and modulus of elasticity, as seen in molded products made from conventional blends. The composition of the present invention can be produced at low cost and is therefore extremely useful in practice. The resin composition of the present invention can be used in fields where engineering plastics are used, such as automobile interior and exterior parts, OA equipment, and electronic parts.

The present invention will now be explained in more detail with reference to Examples and Comparative Examples. In addition, "parts" below means "parts by weight".In addition, each physical property test method is the method shown below, respectively.
It's L.

111= *Tensile test JIS K71131 dumbbell.

Tensile speed 5 mm 7 minutes *Izotsu impact test JIS K711Q, thickness 6.4
mm * Melt viscosity Used by Shioroji Co., Ltd. Soliquid meter MR-1 (temperature 280°C 1 sliding speed 70 sec)
Example 1 Deionized water was poured into a 4-diameter 2-a-volume colven equipped with a stirring blade.
Prepare 00g. A 60% aqueous solution of sodium dodecylbenzenesulfonate (DB NN-60) 4 is added to this. The aqueous solution was heated to 40°C while stirring under a nitrogen stream. Add benzoyl peroxide to 60g of styrene in advance (
A styrene solution in which 6 g of BPO) had been dissolved was added to the heated aqueous emulsifier solution. Stir and level the styrene.
After dispersing in ammonium persulfate (APS
) 0.4g and sodium hyposulfite (S r3 S ) 0.4
g was added to start the polymerization reaction. Then set the liquid temperature to 7
After raising the temperature to 0°C, 220 g of deionized water, 30 g of DBN-6030, 30 g of polyoxyethylene nonylphenyl ether (50 mole adduct of ethylene ogizide; NPE'-50), 730 g of styrene, and methacrylate were added. An emulsion containing 4 g of acid was fed over 5 hours using a dropping funnel to carry out a polymerization reaction. 1. Raise the temperature of the polymerization solution to 80°C and age for 1 hour. After that, 200 g of ethyl acrylate and 6 g of acrylic acid were further fed over 1 hour to carry out a polymerization reaction. After aging for 1 hour, the mixture was cooled to obtain an emulsion. To this emulsion, 100 ml of a 20% aqueous solution of calcium chloride was added to salt out the polymer particles, and then subjected to force W.

The particles obtained by filtration were washed with 5ρ water and heated to 40°C.
It was dried for 5 hours in a blower dryer set to .

The dried product was pulverized to obtain 990 g of dried core-shell type emulsion polymer particles.

Comparative Example 1 A polymerization reaction was started in the same manner as in Example I except that styrene without BPO was used. The temperature of the reaction solution was raised to 60°C, and 220 g of deionized water was added thereto while maintaining this temperature.

DBN-6030g, N1) E-5030g, styrene 73J, ethyl acrylate 200g, methacrylic acid 4g
and an emulsifier consisting of 6 g of acrylic acid FC7-1-
was used for 7 hours (j).At the same time, AP
30 g of a 10% aqueous solution of S and 30 g of a 10% aqueous solution of S II S were each fed over 8 hours to complete the polymerization reaction. An emulsion was obtained by cooling. In the same manner as in Example 1, 985 g of dried emulsion polymer particles were obtained.

The physical properties of the emulsions and polymer particles obtained in Example 1 and Comparative Example 1 are shown in the following table.

table ! ” Using a Minimum Temperature Formation Temperature (MPT) measuring device specified in ASTM D-2354, the temperature at which the dried emulsion changes from white to translucent is 4-0x8.
Measured with Coulter Model N-4 (manufactured by Coulter Electronics) xx Diffcrential Sc for molded products
annning Colorimoter (Rigaku Denki Co., Ltd.)
From the above manufacturing method and glass transition point, in Example I, the core part was approximately 90°C, and the shell part was approximately 90°C (J).
It can be seen that emulsion polymerized particles having a glass transition point about 70°C lower are produced. In addition, although Comparative Example 1 uses the same monomer composition as Example 1 in emulsion polymerization, considering the manufacturing method and glass transition point, emulsion polymerized particles that do not have a core-shell type structure are produced. I understand.

Examples 2 to 4 The dried nonicore/shell type emulsion polymer particles obtained in Example 1 and the polycarbonate resin Kneepilon S-3000 (product of Mitsubishi Gas Chemical Co., Ltd.) were mixed in the proportions shown in Table 2, This was processed using a twin-screw extruder (PCM-30, manufactured by Ikei Iron Works Co., Ltd.) with a diameter of 30 mmφ.
Melt blending was performed at 50° (set to :) to obtain a pellet-shaped polycarbonate resin composition. During blending, volatile matter contained in the blend was removed by drawing a vacuum through a vent installed in the cylinder.

The pellets obtained in this way were
(set at 20°C) for 4 hours. The obtained dried pellets were injection molded using an in-line squirrel-type injection molding machine (the cylinder temperature was set at 250°C). I
A one-ridge test piece specified in IS K7113 was prepared. Similarly, 6. specified in JIS K7110.
A test piece with a thickness of 4 mm was prepared. The physical properties of the molded product were measured using each test piece, and the results are shown in the same table.

Comparative Example 2 A control test piece was prepared by injection molding using polycarbonate resin Kneepilon S-3000 in the same manner as in Example 2-5. Table 2 shows the results of measuring various physical properties of the test pieces.

Comparative Example 3.4 The dried emulsion polymerized particles obtained in Comparative Example 1 and Iupilon S-3000 were mixed in the proportions shown in Table 2, and Example 2-
A polycarbonate resin composition in the form of pellets was obtained by melt blending using the method described in 5. This pellet was subjected to a drying treatment and then injection molded to prepare a test piece. The physical properties of this test piece are shown in the table below.

Comparative Example 2 shows the physical properties of polycarbonate-1/resin alone, and the melt viscosity was significantly lower than that of the present composition (J, Gono) Comparative Example, indicating that molding processability was improved. Moreover, the mechanical properties such as impact resistance of the molded product were also significantly improved compared to Comparative Example 2.

Comparative Example 3.4 uses the same monomer components as in the example, but is a composition in which dried polymer particles that do not have a core-shell type structure are blended with a polycarbonate resin.

Although a decrease in viscosity is observed as in Examples 2 to 5, the mechanical properties of the molded product are significantly decreased.

Claims (2)

[Claims] (1) Dry core-shell type emulsion polymer particles in which the core portion is composed of a thermoplastic resin having a higher glass transition point than the shell portion. (2) A polycarbonate resin composition comprising dried core-shell type emulsion polymer particles in which the core portion is composed of a thermoplastic resin having a higher glass transition point than the shell portion.