JPS61108654A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide the titled resin compsn. having excellent environmental stress cracking resistance and thermal stability, by blending a rubber-contg. styrene resin with a fatty acid vinyl ester polymer. CONSTITUTION:A fatty acid vinyl ester polymer [gel content; 50wt% or below, solubility parameter; 8.8-9.7(cal/cc)<1/2>], composed of a solid obtd. by drying emulsion-polymerized latex without subjecting it to precipitation is used. 0.5-40 pts.wt. said polymer is blended with 100pts.wt. rubber-contg. styrene resin (having a rubber content of pref. 2-30wt%).

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a thermoplastic resin composition containing a rubber-containing styrenic resin that has excellent environmental stress cracking resistance and improved thermal stability.

(Prior art) When rubber-containing styrenic resin comes into contact with chemicals under stress, it is observed that cracks occur and, in severe cases, the resin breaks, but this phenomenon is a phenomenon of environmental stress cracking. It is well known that chemicals such as alcohols, carboxylic acids, alkanes, and alkenes that do not have high solubility in resins are particularly popular.

This phenomenon occurs even when no external force is applied to the resin molded product, when the molding distortion that remains inside the molded product is released by contact with chemicals. It imposes a lot of restrictions.

The content of the rubber component and the molecular weight of the resin component are known to be factors that influence the environmental stress cracking properties of rubber-containing styrene-based w fats. Although the environmental stress cracking property was improved by enlarging the molecule j17 of the resin component, the effect was only insignificant.

By the way, JP-A-56-147841 discloses a copolymer latex of an olefin monomer, a fatty acid vinyl ester monomer, and in some cases a vinyl monopolymer copolymerizable therewith, and a rubber-containing styrenic resin latex. It is disclosed that a resin with significantly improved environmental stress cracking resistance can be obtained by mixing both of these materials in their latex state.

However, although this method improves the environmental stress cracking resistance, when producing the copolymer latex, that is, when emulsion copolymerizing monomers such as fatty acid vinyl esters, the nonionic polymer has a surfactant effect. When using an agent, it is difficult to precipitate the resin from the mixture of copolymerized latex and rubber-containing styrenic resin latex,
Since it is necessary to administer a large amount of inorganic acids and/or water-soluble inorganic salts, it is not only disadvantageous for soil use, but also the precipitating agents that remain in the resin recovered from the latex may affect the thermal stability of the resin. It is undesirable because it has an undesirable effect on

(Problems to be Solved by the Invention) The present invention aims to improve this drawback, and in a composition of a rubber-containing styrenic resin ((trans)) and a fatty acid vinyl ester polymer (E), Difficulty in precipitation (B)
Since there is no need to precipitate the component copolymer latex, the manufacturing process is simplified, and there is no need to add a large amount of precipitating agent, which was required for the precipitation of the (B) acid copolymer. Poor thermal stability of the resin due to residual precipitating agents is reduced, and a rubber-containing styrenic resin with excellent environmental stress cracking resistance and improved thermal stability can be provided.

(Means for solving the problem) That is, the present invention comprises: (A) 100 parts by weight of a rubber-containing styrenic resin;
(B) A copolymer of an olefin monomer and a fatty acid vinyl ester monomer and/or a copolymer of the above two maple monomers and a vinyl monomer that controls the copolymerization (hereinafter referred to as fatty acid vinyl ester/ In the fi11 composition with 0.5 to 40 parts by weight (referred to as li/l/based polymer), the fatty acid vinyl ester polymer is converted into li/based polymer by an emulsion polymerization method. It is a solid obtained by drying the leftover latex without using a precipitation stopper, and its del content is less than 50% by weight, and its solubility parameter is 8.8 to 9.7 (aal /cc) 2.

The monomer that forms the rubber component of the rubber-containing styrene resin, which is the uninvented component (A), includes conjugated diene monomers such as butadiene, imprene, zomethylzotazoene, chloroprene, and cyclopentadiene. , 2,5-norpornathien, 1,4-cyclohexadiene, non-conjugated diene monomers such as 4-ethylidenenorzarene, styrene, α
- Styrenic monomers such as methylstyrene, acrylonitrile, methacrylate trile, methyl methacrylate,
These include (meth)acrylic monomers such as ethyl acrylate, butyl acrylate, hexyl acrylate, and octyl acrylate, and olefin monomers such as ethylene, propylene, 1-butene, imbutylene, and 2-butene, and these si forms Specific examples of rubber components include polybutadiene, polyinzolene, polychloroprene, polystylacrylate, butadiene-styrene copolymer, butadiene-acrylonitrile copolymer, and butadiene. Examples include, but are not limited to, -styrene-methyl methacrylate copolymer, ethylene-globylene-4-ethyrythene/rubornene copolymer, and ethyl acrylate-butyl acrylate copolymer. Additionally, a polyfunctional 15-nyl monomer can be copolymerized during the polymerization of these rubber components, but the polyfunctional vinyl monomers used include divinylbenzene, ethyleneglyfurzomethacrylate)
, 1.3-7” tyrene glycolzomethacrylate, 1
．． 4-7" tyrene glycolzomethacrylate, solobylene glycolzomethacrylate, triallyl cyanurate, triallyltrimethylolpropane trimethacrylate incyanurate, allyl acrylate, allyl methacrylate, vinyl acrylate, vinyl methacrylate, glycysol acrylate, glycysol methacrylate, etc. be.

The method of polymerizing these monomers is not particularly limited, and known techniques such as emulsion polymerization and solution polymerization may be used.

The rubber component in the resin of component (A) does not need to be one type, and may be a mixture of two or more rubber components.

Rubber-containing styrenic resin σ) which is component (1) of the present invention
Monomers constituting the resin component include styrene monomers such as styrene, α-methylstyrene, and vinyltoluene, acrylonitrile, methacryltetranitrile, methyl methacrylate, ethyl acrylate, phthyl acrylate, hexyl acrylate, and octyl acrylate. There are (meth)acrylic monomers, etc., which are used in homopolymerization or copolymerization, but in order to obtain good moldability, it is essential to contain at least 55% by weight of styrene monomers. shall be.

The component (A) used in the present invention is composed of a rubber fraction and a resin fraction as described above, and a graft structure is present at the interface between the rubber component that undergoes globular fermentation and the resin component that is a linked phase. It is necessary to do so. It is known that such a structure can be achieved by the so-called grafting method, in which a part or all of the monomers constituting the resin component are polymerized in the presence of a rubber component. The components can also be manufactured by known graft polymerization techniques.

In order to adjust the content of the rubber component contained in the component (A) having a graft structure, it is possible to mix a separately polymerized resin component with the component (A). The M resin component does not need to have the same composition as the resin component obtained by graft polymerization.

For example, acrylonitrile in the presence of polycitadiene
A resin component obtained by copolymerizing acrylonitrile-styrene-α-methylstyrene can be mixed with component (A) obtained by graft polymerizing styrene-methyl methacrylate.

The resin component (A) used in the present invention preferably has a rubber fraction of 2 to 30 MM%, preferably 5 to 25 MM%. If the component (A) contains less than 1% of the copolymer (!l), the effect of improving the environmental stress cracking property of the resin obtained by mixing it with the copolymer of (!l)i will be insufficient. However, if it exceeds 50% by weight, the rigidity and molding performance deteriorate, which is not preferable.

(A) Specific examples of fill and minute of the present invention,
ABS (acrylonitrile-butadiene-styrene)
Wood) I, heat-resistant ABS (acrylonitrile-butadiene-styrene-α-methylstyrene), 1m, AAS
(acrylonitrile-acrylic acid ester-styrene) resin, AO3 (acrylonitrile-chlorinated polyethylene-styrene) resin 1, u+:s (acrylonide 1
True IPDM-Styrene>m fat, high inno-f Kubo IJ styrene (butazoe/-styrene) resin Ill
There is power.

Next, the copolymer of component (B) used in the present invention is composed of an olefin monomer, a fatty acid vinyl ester monomer, and in some cases, a copolymer of these two and these σ] monomers. It is a copolymer of vinyl monomers, and the olefin monomers mentioned here include ethylene, zolopyrene, 1-butene, 2-butene, inbutene/, cyclopentene, cyclohexene, norbornene, and fatty acid vinyl esters. Monomers include vinyl formate, vinyl acetate, vinyl butyrate, vinyl trimethyl acetate, vinyl chloroacetate, etc. Other vinyl monomers that can be copolymerized with these monomers include styrene, α- Styrenic monomers such as methylstyrene, vinyltoluene, chlorstyrene, dichlorostyrene, tr-tylstyrene, cyanomethyl/, aminostyrene, hydroxystyrene, chloromethylstyrene, acrylonitrile, methacrylatrile, methyl acrylate, methyl methacrylate, ethyl (Meth)acrylic monomers such as acrylate, phthyl acrylate, hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, 2-methoxydiethyl acrylate, 2-hydroxyethyl acrylate, allyl acrylate, glycidyl methacrylate, chloride vinyl, vinylidene chloride and other olein monomers, methyl vinyl ether, ethyl vinyl ether, phenyl vinyl ether and other vinyl ether monomers,
A vinyl ketone monomer such as methyl vinyl ketone or phenyl vinyl ketone, an acrylamide spinning wheel body such as acrylamide or methacrylamide, vinyl pyridine, N-vinyl carbazole, etc. can be used in amounts of 4Nf. Furthermore, if necessary, a polyfunctional vinyl oscillator can be used in combination with the above combinations.

As a polyfunctional vinyl single substance, °C is ethylene glycol dimethacrylate), 1,3-butylene brifur 9 methacrylate, 1,4-zotylene glycol dimethacrylate, zolopylene glycol dimethacrylate, triallyl cyanurate, incyanuric acid Examples include triallyl, trimethylolpropane trimethacrylate, allyl acrylate, allyl methacrylate, and divinylbenzene.

Component (B) of the present invention is produced by an emulsion polymerization method.

There are no particular restrictions on the surfactant used in the emulsion polymerization of component (E), and anionic, cationic, nonionic, and amphoteric surfactants can be used alone or in combination, but they can help maintain emulsion stability during polymerization, foaming, etc. In order to suppress the phenomenon, it is preferable to use the nonionic polymer 1 surfactant in an amount of 5% by weight or more, preferably 20ki% or more of the total amount of surfactant used.

However, we will discuss here/ionic polymer cap surfactant and (
Polypropylene glycol ethylene oxide adducts, higher alcohol ethylene oxide adducts, alkylphenol ethylene oxide adducts, fatty acid ethylene oxide adducts, aliphatic amine ethylene oxide adducts, partially saponified polyvinyl alcohol, polyhydric alcohol higher fatty acid esters, etc. be.

The copolymer of component CB) used in the present invention has a del content of 5
Must be 0% by weight disease-free. However, the del content referred to here is determined by the following method. That is,
1 g of polymer is added to 1001 methyl ethyl ketone and stirred vigorously for 6 hours at room temperature. 1500 of this stuff
Separate the mixture for 1 hour using Orpm and determine the dry weight of the precipitate. The obtained dry weight is multiplied by 100 to obtain the del content (weight ii%).

When component (B) is a copolymer having a Del content of 50% or more by weight, it can be obtained by mixing component (A) in a solid or molten state with component (E) in a latex state. This is undesirable because the impact strength and tensile strength of the resin are reduced.

Must be of a range. However, the solubility parameter here is: John Wiley & 5on
The solubility parameter δ of the copolymer was determined using the solubility parameter values listed in "Polymer Handbook" published by S Company. is calculated by formula (1) from the solubility parameter δn of the individual vinyl homopolymers constituting the copolymer consisting of mm class vinyl fumers and the 100% indigo fraction Wn.

For example, the solubility parameters of polyethylene, polyvinyl acetate, and polybutyl acrylate are 8.1.9.
4.8.8, the solubility parameter δT of a copolymer consisting of 15% by weight of ethylene, 70% by weight of vinyl acetate, and 15% by weight of butyl acrylate is calculated to be 9.1. If the solubility parameter of component (B) deviates from the above range, the impact strength, tensile strength and Environmental stress cracking resistance decreases, which is undesirable.

As mentioned above, the copolymer of (B) ffi is limited in terms of 'rdel content and solubility parameters, but the composition ratio of the copolymer is arbitrary within the range that satisfies the above limitations.

In the present invention, 0.5 to 40 parts by weight, preferably 2 to 60 parts by weight, of a copolymer of the component (B) are mixed with 100 parts of the copolymer of the component (B). Addition amount of coalescence is 0
．． If the amount is less than 5 parts by weight, the effect of improving the environmental stress cracking properties of the resin obtained by mixing with component (A) will not be sufficient, and if it exceeds 40 parts by weight, the effect will not only be saturated, but also This is not preferable because the rigidity decreases.

Further, the copolymer used as component (B) at °C is a copolymer of an olefin monomer and a fatty acid vinyl ester monomer, or a copolymer of -dyl monomer copolymerizable with the above two monomers. It is one of a copolymer and a mixture of the above-mentioned 2-copolymers.

Component CB) of the present invention is a solid obtained by drying latex produced by an emulsion polymerization method without going through a precipitation step. Latex precipitation process'? : There is no particular restriction on the method of drying without oil whitening, and conventional techniques such as spray drying, freeze drying, etc. can be used, and the vine spray drying method is particularly preferably used.

Is latex drying? It can be carried out by supplying it to a spray dryer. Spray dryers are classified into rotating disk type, two-fluid nozzle type, pressure nozzle type, etc. depending on the spray method, and are also classified into co-current type, counter-current type, parallel-counter flow type (mixed type), etc. depending on the hot air method. However, the present invention is not limited by these methods.

In order to prevent the adhesion of the fatty acid vinyl ester thread-coated solid obtained by spray drying 1-, an anti-adhesive agent can be added during rrJi spray drying, and examples of anti-adhesive agents include calcium carbonate, calcium sulfate, etc. , barium sulfate,
Inorganic substances such as aluminum hydroxide, calcium silicate, silica, talc, clay, magnesium oxide, zinc oxide, calcium stearate, magnesium stearate, barium stearate, zinc stearate, stearic acid, stearyl alcohol, stearamide, methylene Higher fatty acids such as bis-stearylamide and ethylene bis-stearylamide and their derivatives? Lipropylene,
Examples include thermoplastic resin powder such as polyvinyl chloride, polystyrene, As resin, ABS resin, polyvinyl alcohol, polyamide, polyester, and thermosetting resin powder such as phenol resin and urea resin.

In the present invention, the ((conversion)) component and the (B) component are mixed, but the (A) component to be mixed may be in any of an emulsified state, a solution state, or a solid state.((conversion)) When the components are solid, after mixing the (A) component and the (B) component using a mixing device such as a Henschel mixer, tumbler, super mixer, ribbon blender, or V-type mixer, The composition can be prepared by supplying the mixture to a melt-kneading device such as a Banbury mixer, an intensive mixer, a Miwastruder, a co-kneader, an Ewastruder, or a roll. It is also possible to supply the composition directly to a bath melt kneading device.

Furthermore, the thermoplastic resin powder of the present invention can contain pigments, dyes, stabilizers, dispersants, reinforcing materials, fillers, weathering agents, antistatic agents, foaming agents, lubricants, and the like.

The following margin (Examples) The present invention will be further explained with reference to the following Examples, in which all parts and amounts described in the Examples are expressed on a weight basis.

Reference Example Spray Drying of Known Ingredients An ethylene-vinyl acetate copolymer latex consisting of 85% ethylene 151 vinyl acetate was spray-dried by supplying it to a co-current spray dryer equipped with a rotating disc type atomizer. The drying equipment has a diameter of 2.5 m and a height of 2
．． It had a cylindrical shape with a length of 5 m, and air was used as the hot air. The hot air flow rate is 700"3/hour, and the hot air inlet temperature is 10
The 0°C1 outlet temperature was 50-55°C. Silica fine powder Song was used as an anti-blocking agent and was sprayed from near the top of the tower at a ratio of 5% to the polymer.

The ethylene-vinyl acetate copolymer solid recovered from the apparatus had a moisture content of 0.75% and was in powder form. Moreover, the r content of the copolymer is 18%, and the formula (
The swamp solubility parameter calculated from 1) is 9.2 (Ca
l/cc) LA Te9.

Using the same spray dryer, Tables 2B-2 to B-9
Spray drying was carried out.

Example 1 The IAI component (solid) shown in Table 1 and the component (provided) shown in Table 2
solid) in the proportions shown in Table 6 into a Henschel mixer, and further added 2 parts of ethylene bis stearylamide and TNP.
(IJy stabilizer) 0.2 part was added and mixed. The contents were supplied to VC-40 (vented single-screw extruder) manufactured by Chuo Kikai Seisakusho Co., Ltd., and melt-kneaded to obtain pellets.

A molded article was made from the obtained pellet and its physical properties were evaluated, and the results are shown in Table 6.

In Table 3, Experiments A61 to 5 show the influence of (g) the amount of component added, Experiments A66 to 10 show the influence of the type of component, and Experiments A61 to 14 show the influence of (d) the amount of component. It shows the influence of type. As is clear from Table 6, the compositions in any combination have excellent physical properties and thermal stability.

Comparative Example 1 As CB+ component (s-5L (B-8), (B-9
] A molded article was prepared in the same manner as in Example 1, except that 1615.] was used, and the physical properties were evaluated.
16.17.

Comparative Example 2 (A-1) 125 parts of latex (latex weight, solid content 30%) and (B-1) 18 parts of latex (latex weight, solid content 55%) were mixed in a latex state, and 35% Hydrochloric acid 0.65 part, calcium chloride 6.7
A slurry was obtained by stirring at 93° C. for 5 minutes using a male blade. Wet powder 46 obtained by dehydrating this slurry
The moisture content was higher than that of the wet powder obtained by precipitating only latex (A-1) under the same precipitation conditions.

After the wet powder was dried, 62.5 parts of (A-6), 2.0 parts of ethylene bisstearoids, TNpO, and 2fH1 were mixed together in a Henschel mixer, and the mixture was made into a pellet in a single extruder.

A molded article was made from the obtained PVC and its physical properties were evaluated, and the results are shown in Table 4, Experiment 418.

In addition, calcium chloride in the dry powder obtained by precipitating only latex (A-1) was 660 ppm, but when a mixture of latex (A-1) and (B-1) was precipitated, it was found to be 660 ppm. Calcium chloride in the obtained dry powder was determined to be 5300 ppm.

Comparative Example 3 10 parts of the @) component solid obtained by adding boric acid aqueous solution to the @) component latex in Table 2 (B-1) to precipitate a polymer and drying it was mixed with 37.5 parts of (A-1). , (person-6) 62.5fl
, ethinone bisstearamide 2.0 parts, TNP
2 parts of O, and pelletized using a single screw extruder.

A molded article was made from the obtained pellet and its physical properties were evaluated, and the results are shown in Table 4, Experiment 419.

Comparative Example 4 57-5 parts of (A-1), 62 parts of (A-6) as a prisoner component.
Pellets were obtained in the same manner as in Example 1 except that 45 parts of (B-1) was used as the 5'B, @+acid component.

A molded article was made from the obtained pellet and its physical properties were evaluated, and the results are shown in Table 4, Experiment 420.

Comparative Example 5) Table 4 shows the physical property evaluation results for the ingredients only.
23.24.

In these tests, all physical property measurements were obtained by the following methods.

(1) Tensile yield point...ASTM D-6
58+217 (Jit impact strength...ASTM D-2
56 (3) Thermal stability test method The resin was allowed to stay inside the cylinder of a 2-ounce injection molding machine for 10 minutes with a cylinder temperature of 250'C, and then injection molded.
The whiteness W]o of Nippon Gyoiro Kogyo Co., Ltd.
Measured using TERMODEL ND-101DC.

In addition, the whiteness WO of a molded product injected without performing a residence operation using an injection molding machine under the same conditions is measured. Whiteness change I”
Find D-(Wo “15)/WQX100, and WD<
Evaluate 10 as A% 10 < Frame 20 as B1°C and 20 as C. With the resin of WD) 2 Q, even if the molded product is injected without performing the dwell operation, the Wo of the molded product will vary depending on the slight difference in the molding temperature, which is not preferable.

(A) Environmental stress cracking test method, rrsK7113 1 Give a 50 mm deflection to a deformed test piece, fix it in a jig, and heat it with wood vinegar @ (ESCR-AC) or ethylene glycol monoethyl ether (ESC).
R-KG) is applied and left at 23°C, the time to breakage is expressed in minutes.

(Effects of the Invention) As explained above, the present invention provides a composition of a copolymer (containing methylene resin) and a fatty acid vinyl ester copolymer CB+, and according to the composition of the present invention, precipitation Since there is no need to precipitate the component latex by adding a precipitating agent, the manufacturing process is not only simplified and energy-saving, but also the amount of precipitating agent remaining in the final composition can be kept to a minimum. This improves the thermal stability of the final composition. By limiting the del content and solubility parameters of the copolymer of the a31 component to the above range, it is excellent in forming pillars under environmental stress and has excellent thermal stability. Considering that the site was located at a site that could potentially come into contact with other products, its industrial value is enormous.

Claims (1)

[Claims] (A) 100 parts by weight of a rubber-containing styrenic resin; (B)
A copolymer of an olefin monomer and a fatty acid vinyl ester monomer and/or a copolymer of a vinyl monomer copolymerizable with the above two monomers (hereinafter referred to as fatty acid vinyl ester polymer) ) 0.5 to 40 parts by weight, the fatty acid vinyl ester polymer is a solid obtained by drying latex produced by an emulsion polymerization method without going through a precipitation step, and Its gel content is less than 50% by weight and its solubility parameter is 8.8-9.7 (
A thermoplastic resin composition characterized in that the thermoplastic resin composition has a molecular weight of 1.2 cal/cc).