JPS6037828B2 - Impact resistant resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a resin composition for profile extrusion molding that includes a polyvinyl chloride resin and has excellent impact strength.

．． So-called profile extrusion products such as pipes, sashes, and deck materials made of vinyl chloride resin are widely used in building materials and other fields.

However, due to the major drawback of vinyl chloride resins, which is their resistance to impact, the use of impact modifiers is a prerequisite when manufacturing these products. Examples of modifiers used in these applications include MBS resin and chlorinated polyethylene, but sufficient impact resistance cannot be obtained in either case. This phenomenon is thought to occur because the profile extrusion molding method is generally carried out with a so-called high inertia formulation, which results in insufficient kneading during processing and the modifier is not uniformly dispersed in the vinyl chloride resin. As a result of intensive research on this point, the present inventors have found that in a composition consisting of vinyl chloride resin and MBS resin, the amount of fermentation components caused by the emulsifier in M-Shi resin is kept to a low level, and at the same time, hindered phenol-based By using an antioxidant and ethylene diamino tetraacetate, the MBS resin is sufficiently dispersed in the vinyl chloride resin even during profile extrusion molding due to the so-called highly slippery formulation.
We have reached the surprising fact that molded products that exhibit significantly higher impact strength than molded products using conventional M and old S resins, and have excellent thermal stability and processability, have developed the present invention. completed.

The present invention consists of 50 to 9 parts by weight of vinyl chloride resin, 25 to 75 parts by weight of a copolymer rubber containing polybutadiene or butadiene at 5% by weight or more, and 30 to 7 parts by weight of methyl methacrylate.
25 to 75 parts by weight of a monomer mixture consisting of 30 to 7 weight % of styrene, and 0 to 2 weight % of a monomer copolymerizable with these are mixed with 0.1 weight % of a carboxylic acid salt emulsifier.
~1 parts by weight (based on 100 parts by weight of the polymer) of MBS resins 1 to 5, which were graft-polymerized in the presence of 100 parts by weight of MBS resins to 1000 ppm or less of brewing components due to emulsifiers in the resulting resin, 'C} a hindered phenolic antioxidant composed of carbon, hydrogen, and oxygen and/or carbon;
An impact-resistant resin composition for profile extrusion molding consisting of 0.01 to 2 parts by weight of a hindered phenolic antioxidant composed of hydrogen, oxygen and sulfur, and 0.1 to 1 part by weight of ethylenediaminetetraacetate. .

The vinyl chloride resin used in the present invention contains polyvinyl chloride or 7% by weight or more of vinyl chloride, vinyl bromide,
It means a copolymer with a monomer selected from vinyl chloride, vinyl acetate, (meth)acrylic acid or its ester, or less than % by weight of the monomer mixture 3, and is produced by commonly known bulk, suspension or emulsion polymerization. Manufactured.

In addition, the polybutadiene or copolymer rubber mainly composed of butadiene and styrene used in the present invention is a carboxylic acid salt represented by a salt of stearic acid, oleic acid, rosin acid, sarcosic acid, etc. or a salt of a derivative thereof. It is produced by emulsion polymerization using emulsifiers alone or in combination.

Furthermore, in addition to these emulsifiers to the extent permitted by the physical properties as a modifier, sulfate emulsifiers such as alkyl sulfate ester salts, higher alcohol sulfate ester salts, sulfate ester salts containing amide or ester bonds, naphthalene sulfonate salts, etc. Sulfonate emulsifiers such as formalin condensates, alkylbenzene sulfonates, dialkyl sulfosuccinates, higher alcohol sulfonates, and other emulsifiers such as alkyl phosphates may also be used in combination. In addition to butadiene and styrene, the components of the copolymer rubber may include monomers that can be copolymerized with these, such as butyl acrylate, vinyl chloride, acrylonitrile, methyl methacrylate, and the like. Further, the rubber may be crosslinked by using these monomers together with a crosslinking agent that can be polymerized, for example, a divinyl compound such as divinylbenzene, or a methacrylic acid ester such as ethylene glycol dimethacrylate. Chain transfer agents such as , thioglycolic acid esters, etc. can also be used to adjust the gel content of the rubber. A particularly preferred rubber component is a monomer consisting of 5% by weight or more of butadiene, 5 to 5% by weight of styrene, 0 to 2% by weight of a copolymerizable monomer, and 0 to 5% by weight of a crosslinking agent. It is obtained by emulsion polymerization in the presence of a polymerization degree regulator of % or less.

If a rubber having a composition outside this range is used, the desired impact resistance will not be obtained and the processability will be poor. Next, in the graft polymerization, 30 to 7% by weight of methyl methacrylate and 30 to 7% by weight of styrene were added as graft monomers to the above rubber component.
A monomer mixture consisting of 7% by weight and 0 to 2% by weight of a monomer copolymerizable with these is prepared using a carboxylate emulsifier.

In this case, of course, other emulsifiers may also be used in combination within the range permitted by the physical properties of the modifier. Examples of copolymerizable monomers include unsaturated nitriles such as acrylonitrile and methacrylonitrile, and acrylic esters such as ethyl acrylate and butyl acrylate. During graft polymerization, a polyfunctional monomer such as divinylbenzene, ethylene glycol dimethacrylate, triallyl cyanurate, etc. is used as a crosslinking agent in an amount of 5% by weight or less.
Alternatively, an alkyl mercaptan or the like may be added as a polymerization degree regulator in an amount of 5% by weight or less. Outside the above range of graft monomer composition, vinyl chloride resin and MB
The balance of compatibility with the S resin is disrupted, leading to poor dispersion of the M old S resin during molding, resulting in a decrease in impact resistance.

The ratio of the rubber part to the graph part is preferably such that the amount of the rubber part is in the range of 25 to 75 parts by weight per 100 parts by weight of the polymer. 2
If the amount is less than 5 parts, it is necessary to add a large amount of M old S resin to the vinyl chloride resin in order to obtain the desired impact resistance, and processability also decreases.

If it exceeds 75 parts, the fluidity of the composition decreases, making it impossible to obtain a good profile extrusion.

Here, the graft monomers may be graft-polymerized as a mixture of the monomers, or one of the monomers may be graft-polymerized first, and then the other monomers are graft-polymerized, and so on.
Graft polymerization may be carried out in stages.

Further, these monomers may be continuously added to the polymerization system to perform graft polymerization, or they may be added to the polymerization system in portions and graft polymerized. In the present invention, it is essential that the graft polymerization is carried out in the presence of 0.1 to 1 part by weight (based on 100 parts by weight of the polymer) of a carboxylate emulsifier.

Next, this latex is coagulated, washed, and dried, but the resulting resin contains 1000 pp of brewing components caused by the emulsifier.
If it is more than m, the polymer particles will not be dispersed in the vinyl chloride resin during molding due to the tenacity effect caused by the brewing ingredients, and therefore, not only will only a product with low impact resistance be obtained,
Since it contains a large amount of acid components, it has low thermal stability and poor long-run performance during processing. For this reason, it is desirable that the amount of brewing components in the polymer be as low as possible. Methods of suppressing the brewing components caused by emulsifiers in the resin to 100 pm or less include methods of extracting acid components by coexisting with the polymer in the form of salts such as soap (freeze drying, imitation mist drying, etc.), salt folding, etc. There are two methods: a method of extracting the acid component with a solvent, etc. Among these methods, the most economical and industrially usable method is the salting-out method, and preferred salts for salting-out include sodium, potassium, and calcium salts. Next, a hindered phenol antioxidant is added at 0.00% to prevent coloring during processing due to the salt contained in the M old S resin.
It is added in an amount of 0.01 to 2 parts by weight. Examples of these antioxidants include 2,6-di-tert-butyl-p-cresol, 2,2-methylene-bis-(4-methyl-6
-tert-butylphenol), 4,4'-butylidenebis(3-methyl-6-tert-butylphenol), 4,4-thiobis(6-tert-butyl-3-methylphenol), bis(3-methyl-6-tert-butylphenol), Examples include 4-hydroxy-5-tertiary methylbenzyl) sulfide, but these can also be used in combination with antioxidants such as thiodipropionate and phosphite. Adding an antioxidant in an amount of 5% by weight or more (based on the MBS resin) not only reduces processability but is also economically disadvantageous. In addition, ethylenediaminetetraacetate, such as ethylenediamine disodium salt, ethylenediamine tetrasodium salt, etc., can be added in the range of 0.01 to 1 part by weight for the same purpose, but by using both together, thermal coloring,
Synergistic effects such as prevention of fading during processing and the need for a small amount of stabilizer are obtained, and the processability of the pinyl chloride resin composition according to the present invention is improved. The hindered phenolic antioxidant and ethylenediaminetetraacetate may be added to the latex during polymerization or during coagulation or processing. The obtained MBS resin is mixed with vinyl chloride resin in an appropriate ratio.

The mixing ratio can be selected according to the degree of processability, impact resistance, etc. depending on the application, but generally when performing profile extrusion molding,
A preferred mixing ratio is in the range of 70 to 97 parts by weight of vinyl chloride resin and 3 to 3 parts by weight of M old S resin. When these are mixed, a commonly known mixing device such as a mixing roll, a Banbury mixer, an extruder, etc. is used. Prior to kneading and molding, preliminary mixing may be performed using a ribbon blender, Henschel mixer, or the like. In the following examples, parts and % mean parts by weight and % by weight, respectively. Example 1 In an autoclave equipped with a Azusa machine, 45 parts of butadiene, 15 parts of styrene, and 0.5 parts of divinylbenzene were mixed with 20 parts of water.
1.5 parts of potassium oleate as an emulsifier, 0 parts of diisopropylbenzene hydroperoxide as an initiator
．． Rubber latex (conversion rate 98%, Particle size 0.1
1), 0.1 part of Rongalit was added, and then a mixture of 2 groups of styrene and 0.05 parts of cumene hydroperoxide was added dropwise over about 30 minutes to polymerize, and the temperature was raised to 60 CO. and hold for 160 minutes.

Thereafter, a mixture of 20 parts of MMA and 0.05 parts of cumene hydroperoxide was added dropwise over about 60 minutes to polymerize, and the mixture was further concentrated for 60 minutes. Obtained MBS
The latex containing the resin was cooled to room temperature, and 2,6-tert-butyl cresol 0. After immersing 0.1 part of ethylenediamine disodium salt, it is salted out with an aqueous solution containing sodium chloride, coagulated, dehydrated, washed with water, and dried to obtain M old S resin.

15 parts of the obtained MBS resin, polyvinyl chloride (polymerization degree 7)
00) 85 parts, tribasic lead sulfate 2.5 parts, dibasic lead sulfate 0.6 parts, bell stearate 1.8 parts, calcium stearate 0.8 parts, Metabrene P-700 (registered trademark,
0.5 part of Mitsubishi Rayon processing aid) was mixed in a Henschel mixer (300 pm) and heated to 120 oo.

The obtained powder mixture was transferred to the 25 side ◇ extruder (dice temperature 1
9yo) into a square bar, which was cut to measure the lzod impact strength. As a comparative example, evaluations of the same as in Example 1 except that the coagulant was sulfuric acid (Comparative Example 1) or a mixture of hydrochloric acid and sodium chloride (Comparative Example 2) are also shown in Table 1. Table 1 As is clear from Table 1, the composition of the present invention exhibits significantly higher impact resistance than the composition containing a large amount of brewing ingredients.

Furthermore, even if the coagulant is a salt-acid combination system, the impact resistance will not improve unless the amount of the fermentation component in the M-light S resin is 1000 ppm or less. Example 2 A composition obtained in the same machine as Example 1 except that the added amount of the hindered phenol antioxidant and ethylenediaminetetraacetate was changed was 185 qo test roll.
After mixing for 0 minutes, the coloring properties of the roll specimens were compared.

The results are shown in Table 2. As is clear from Table 2, compositions that do not contain the hindered phenol antioxidant and ethylenediaminetetraacetate tend to be colored.

Table 2 Example 3 Profile extrusion and lzod impact strength were measured in the same manner as in Example 1, except that calcium nitrate was used as the coagulant and the mixing ratio of M mottled resin and pinyl chloride resin was changed.

The results are shown in Table 3. As is evident from Table 3, compositions within the scope of the invention exhibit high impact resistance.

Table 3

Claims (1)

[Claims] 1 (A) 50 to 999 parts by weight of vinyl chloride resin, (B)
Contains 50% by weight or more of polybutadiene or butadiene,
Copolymer rubber mainly composed of butadiene and styrene 2
5 to 75 parts by weight, 25 to 75 parts by weight of a monomer mixture consisting of 30 to 70% by weight of methyl methacrylate, 30 to 70% by weight of styrene, and 0 to 20% by weight of a monomer copolymerizable with these, and a carboxylic acid salt emulsifier. 0.1~1
1 to 50 parts by weight of MBS resin, which was graft polymerized in the presence of 0 parts by weight (based on 100 parts by weight of the polymer) and the acid component resulting from the emulsifier in the resulting resin was 1000 ppm or less, (C) carbon, hydrogen, and 0.01 to 2 parts by weight of a hindered phenolic antioxidant composed of oxygen and/or a hindered phenolic antioxidant composed of carbon, hydrogen, oxygen and sulfur, (D) ethylenediaminetetraacetate 0 .1 to 1 part by weight of an impact-resistant resin composition for profile extrusion molding.