JPH0123494B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is a graft copolymer (A) [hereinafter referred to as graft copolymer ( A)] and a partially crosslinked vinyl chloride resin (B), or a partially crosslinked vinyl chloride resin (B) and a vinyl chloride resin (C). In order to improve the impact resistance, processability, etc. of vinyl chloride resins, it is known that polymers obtained by graft polymerization of aromatic vinyl compounds, alkyl acrylates, alkyl methacrylates, vinyl cyanide compounds, etc., are blended with rubber. It is being Such compositions are generally used in many parts for vehicles, housing materials for audio equipment, parts for communication equipment, parts for OA equipment, etc. by injection molding. However, in recent years, in vinyl chloride resin molded products in various fields, so-called wash-out molded products that have lost the plastic luster have come to be preferred, and various wash-out techniques have been developed. For example, techniques include (1) using a large amount of filler, (2) acrylic painting, and (3) embossing. However, method (1) reduces thermal stability, impact resistance, etc., method (2) increases the number of painting steps and costs due to paint, and method (3) results in embossed metal. This method requires a mold, is expensive to use, and has drawbacks such as clogging of the embossed part with resin during use, resulting in spots, and these are all insufficient techniques. In recent years, as a technique that does not have the above-mentioned drawbacks, a stripping technique using partially crosslinked vinyl chloride resin has been attracting attention. It is especially used to impart rubber elasticity and rubbery feel to soft vinyl chloride resin molded products. For example, a proposal was made to obtain a partially crosslinked vinyl chloride resin using a crosslinking agent such as diallyl phthalate, diallyl maleate, polyethylene glycol diacrylate, or polyethylene dimethacrylate, and to utilize a composition using this.
No. 54-80854, JP-A No. 56-5840, JP-A No. 56-
92024, etc.). However, in ABS/PVC blend compositions, which are hard resin compositions with a high ABS content, which are molded at high temperatures such as in-die extension molding, the dissolution technology using partially crosslinked vinyl chloride resin is not used. This is because partially crosslinked vinyl chloride resins generally have poor thermal stability and are thought to reduce the impact strength of molded articles obtained from ABS/PVC blend compositions. In view of the above-mentioned actual situation, the present inventors have conducted extensive research and found that polybutadiene or 50% or more (by weight, the same shall apply hereinafter) of butadiene and 50% or less of monoolefin monomer that can be copolymerized with it. In the presence of 15 to 80 parts (parts by weight, same hereinafter) of a copolymerized rubbery polymer, one or more selected from the group consisting of alkyl acrylates, alkyl methacrylates, and vinyl cyanide compounds. Monomer mixture consisting of a monomer and an aromatic vinyl compound
Partially crosslinked vinyl chloride, which is a polymer obtained by copolymerizing a graft copolymer (A) obtained by copolymerizing 85 to 20 parts of vinyl chloride or a monomer mixture containing 60% by weight or more of vinyl chloride as a main component. In the resin composition consisting of resin (B) or partially crosslinked vinyl chloride resin (B) and vinyl chloride resin (C), the graft copolymer
40 to 60 parts of (A), 60 parts of partially crosslinked vinyl chloride resin (B) or partially crosslinked vinyl chloride resin (B) + vinyl chloride resin (C)
By using a vinyl chloride resin composition containing ~40 parts and blending the gel fraction in (B) or (B) + (C) to 0.3 to 30%, surprising results can be obtained. In particular, they discovered that it can be used for dissolution without reducing impact strength or thermal stability, leading to the completion of the present invention. In the present invention, the rubbery polymer is polybutadiene latex or 50% or more butadiene and 50% or less monoolefin monomer copolymerizable with this, such as aromatic vinyl compounds such as styrene, methyl acrylate, ethyl acrylate, It is used as a copolymer latex with alkyl acrylates such as butyl acrylate, alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, and butyl methacrylate, and vinyl cyanide compounds such as acrylonitrile. Alkyl acrylate such as methyl acrylate, ethyl acrylate, 2-ethylhexyl acrylate, butyl acrylate, alkyl acrylate such as methyl methacrylate, ethyl methacrylate, 2-ethylhexyl methacrylate, butyl methacrylate in the presence of 15 to 80 parts of a rubbery polymer. Monomer mixture 85 to 20 consisting of one or more monomers selected from vinyl cyanide compounds such as methacrylate and acrylonitrile, and aromatic vinyl compounds such as styrene and α-methylstyrene.
A graft copolymer (A) is obtained by copolymerizing the above parts. The composition of the graft copolymer (A) is particularly preferably as follows. Namely, rubbery polymer 20-65%, aromatic vinyl compound 5-50%, alkyl acrylate 1-50%, alkyl methacrylate 10-50%,
Preferably, the vinyl cyanide compound is 0 to 40%. The graft copolymer (A) is produced by known emulsion polymerization. Rubber latex is dispersed and stirred in an aqueous medium in which an emulsifier is dissolved, and the monomer mixture is added and polymerized in the presence of a polymerization initiator. Partially crosslinked vinyl chloride resin (B) used in the present invention
contains vinyl chloride alone or with vinyl chloride as the main component
The gel contained in the partially crosslinked vinyl chloride resin (B) is obtained by copolymerizing a monomer mixture containing 60% or more and a crosslinking agent in an aqueous medium by emulsion polymerization or suspension polymerization. The fraction is preferably 0.3 to 40%, particularly preferably 5 to 50%. When the gel fraction is less than 0.3%, sufficient effects cannot be obtained even when used for eradication, and when it exceeds 40%, impact resistance and thermal stability tend to deteriorate. Further, the average degree of polymerization of the uncrosslinked vinyl chloride resin contained in the partially crosslinked vinyl chloride resin (B) is preferably 300 to 800, particularly preferably 400 to 550. The degree of polymerization
When it is less than 300, impact strength decreases, and when it is 800 or more, fluidity decreases, which tends to be preferable. This degree of polymerization can be adjusted to any desired degree by adding an appropriate amount of a polymerization degree regulator and further changing the polymerization conditions appropriately, but when carrying out the polymerization reaction, The reaction temperature of 60-80
It is particularly preferable to adjust the temperature to ℃. As the polymerization degree regulator, compounds having a hydroxyl group in the molecule such as 2-mercaptoethanol and 3-mercaptopropanol, mercaptoacetic acid, and alkyl esters of mercaptoacetic acid are particularly preferred. Partially crosslinked vinyl chloride resin (B) used in the present invention
Examples of crosslinking agents used in the production of 1. Diacrylate compounds such as 3-butylene diacrylate or polyethylene glycol diacrylate, trimethacrylate compounds such as trimethylolpropane trimethacrylate, triacrylate compounds such as trimethylolpropane triacrylate, or oligomers thereof, or 1,2-polybutadiene, epoxidized 1,2-polybutadiene,
Examples include polybutadienes such as 1,2-polybutadiene with a hydroxyl group at the end and 1,2-polybutadiene with a carboxyl group at the end. Among them, crosslinking agents represented by the following general formulas (), (), or () are particularly preferred because they have particularly excellent weather resistance and thermal stability. (In the formula, R ₁ is a hydrogen atom or a methyl group, R ₂ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ₃ , R ₄
is a hydrogen atom, a methyl group, an ethyl group, -
Atom or group selected from CH ₂ CH ₂ COOH group, i,
j is an integer of 1 to 5, m and n are integers of 1 to 10, l is 0 or an integer of 1 to 20, and x represents a chlorine atom, a bromine atom, or a hydrogen atom. ) In the partially crosslinked vinyl chloride resin (B) used in the present invention, the monomer forming the main chain is vinyl chloride alone, or at least 60% vinyl chloride and a vinyl monomer copolymerizable therewith. It is a mixture of Monomers copolymerizable with vinyl chloride include vinyl esters such as vinyl acetate, vinyl ethers such as methyl vinyl ether, acrylic esters such as methyl acrylate, methacrylic esters such as methyl methacrylate, acrylic acid,
Examples include methacrylic acid, maleic esters, fumaric esters, maleic acid, fumaric acid, maleic anhydride, fumaric anhydride, aromatic vinyl compounds, vinylidene halides, and monoolefins. What is the vinyl chloride resin (C) used in the present invention? Polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, vinyl chloride-acrylic acid ester copolymer, vinyl chloride-methacrylic acid ester copolymer, vinyl chloride-ethylene Examples include copolymers, vinyl chloride-alkyl vinyl ether copolymers, vinyl chloride-propylene copolymers, and the like. In the present invention, as mentioned above, it is particularly preferable to use a partially crosslinked vinyl chloride resin with a gel fraction of 0.3 to 40%, but the PVC component in the composition is a partially crosslinked vinyl chloride resin or a partially crosslinked vinyl chloride resin. The gel fraction contained in + vinyl chloride resin is
It needs to be between 0.3 and 30%. i.e. gel fraction 30%
Partially crosslinked vinyl chloride resin with a content exceeding 40% must be mixed with vinyl chloride resin to have a gel fraction of 0.3 to 30% before use. If the gel fraction exceeds 30%, impact strength and thermal stability will be insufficient;
This is because if the amount is less than that, sufficient dissipation effect cannot be obtained. The resin composition of the present invention can be molded by adding heat stability agents, lubricants, antioxidants, flame retardants, ultraviolet absorbers, processing aids, pigments, plasticizers, etc. as necessary, and molding the resin composition. It is used to manufacture various products. As the heat stabilizer used during the molding process, known heat stabilizers used for vinyl chloride resin can be used, such as tin-based stabilizers such as octyltin maleate, tribasic lead sulfate, etc. Lead stabilizers, metal soaps, Ca-Zn stabilizers, Ba stabilizers, etc. can be used alone or in combination. Further, as the lubricant, known lubricants such as polyethylene wax-based lubricants, stearic acid-based lubricants, and alcohol-based lubricants can be used alone or in combination. Examples of the plasticizer used for the purpose of improving processability include known plasticizers such as phthalic acid plasticizers such as dioctyl phthalate, polyester plasticizers, phosphate ester plasticizers, and epoxy plasticizers. Can be used alone or in combination. Furthermore, flame retardants that can be used in the present invention include metal oxides such as zinc oxide, antimony trioxide, and boron oxide, metal hydroxides such as aluminum hydroxide and zinc hydroxide, bromine compounds, and chlorine compounds. can give. Graft copolymer (A) and partially crosslinked vinyl chloride resin (B) or partially crosslinked vinyl chloride resin (B) in the present invention
It is preferable to mix it with the vinyl chloride resin (C) after forming it into a powder using a normal method, but it is also possible to mix aqueous dispersions. Next, the compositions of the present invention will be further clarified by Examples, but they are not intended to limit the scope of the present invention. Production example 1 (a) Production of graft copolymer (A) Emulsion polymerization was carried out at 60°C for 6 hours based on the charging ratio shown in Table 1, and graft copolymer (A) (hereinafter referred to as G
-1).

[Table] (b) Production of partially crosslinked vinyl chloride resin (B) Based on the compositions in Tables 2 and 3, at 63℃
Suspension polymerization was carried out for 15 hours, followed by dehydration and drying to obtain partially crosslinked vinyl chloride resins () to () in Table 3.
Table 3 shows the soluble polymerization degree and gel fraction of the obtained resin. The soluble polymerization degree was determined from the specific viscosity of the nitrobenzene solution based on JIS K6721. Moreover, the gel fraction was measured by the same method as described in Examples 1 to 7 below.

【table】

【table】

[Table] Examples 1 to 7 Based on the compositions shown in Table 4, the blended powders were roll-kneaded at 160°C for 10 minutes and pressed at 170°C for 30 minutes, and the following physical properties were measured for test pieces obtained. The results are shown in Table 4. In addition, each physical property value was measured as follows. (a) Gel fraction This is a value calculated by extracting with tetrahydrofuran for 22 hours using a Soxhlet extractor and determining the dry weight of the extraction residue remaining on a 350 mesh filter. (b) Izot impact value Measured according to ASTM D256-54T. (c) Heat distortion temperature Measured according to ASTM D648-56. (d) Koka type flow 150Kg load, 1mmφ x 10mm nozzle, measured at 190℃. (E) Heat deformation resistance One end of a 2 mm x 10 mm x 150 mm press plate was fixed in a 72℃ air bath so that the press plate was horizontal, and the deviation from the horizontal of the unfixed end after 3 hours (mm) shows. (f) Thermal stability Gear oven (at 190℃)
Visually evaluate the degree of coloring of the press plate (for 180 minutes), and evaluate it as ◎ if there is no coloring, 〇 if there is almost no coloring, △ if there is slight coloring, and × if there is coloring.
Determined as. (G) Erasing property Visually observe the sheet obtained by roll-kneading as described above, and rated ◎ if the effluent property is good, 〇 if it is almost good, and △ if there is some rippling. If there is a barb, it is evaluated as ×. (H) Weather resistance The Izot impact value of a bar manufactured based on ASTM D256-54T was determined after it was aged for 200 hours using a Sunshine Weather-O-meter. The conditions were 63°C, water spraying for 18 minutes every 2 hours, and the test sample was turned over every 20 hours. Examples 8 to 9 Partially crosslinked vinyl chloride resin () was mixed with Kanebiyur S-400 (vinyl chloride resin, manufactured by Kanebuchi Chemical Industry Co., Ltd.), and the compositions shown in Table 4 were prepared in the same manner as in Example 1. Roll kneading and press molding were performed, and the physical properties of the obtained test pieces were measured in the same manner as in Example 1. The results are shown in Table 4. Comparative Examples 1 to 4 In the same manner as in Example 1, test pieces were prepared based on the compositions shown in Table 4, and the physical properties were measured in the same manner as in Example 1. The results are shown in Table 4.

【table】

Claims (1)

[Claims] 1. Polybutadiene or a rubbery polymer obtained by copolymerizing 50% by weight or more of butadiene and 50% by weight or less of a monoolefin monomer that can be copolymerized with the polybutadiene 15
alkyl acrylate, in the presence of ~80 parts by weight;
A graft copolymer obtained by copolymerizing 85 to 20 parts by weight of a monomer mixture consisting of one or more monomers selected from the group consisting of alkyl methacrylates and vinyl cyanide compounds and an aromatic vinyl compound. Partially crosslinked vinyl chloride resin (B) or partially crosslinked vinyl chloride resin, which is a polymer obtained by copolymerizing the polymer (A), vinyl chloride, or a monomer mixture containing 60% by weight or more of vinyl chloride as a main component, and a crosslinking agent. (B) and a vinyl chloride resin (C),
40 to 60 parts by weight of graft copolymer (A), partially crosslinked vinyl chloride resin (B) or partially crosslinked vinyl chloride resin (B) +
Use 60 to 40 parts by weight of vinyl chloride resin (C), and
A vinyl chloride resin composition prepared by blending (B) or (B)+(C) so that the gel fraction is 0.3 to 30% by weight. 2. Claim 1, wherein the gel fraction contained in the partially crosslinked vinyl chloride resin (B) is 0.3 to 40% by weight.
Compositions as described in Section. 3. The composition according to claim 1 or 2, wherein the uncrosslinked vinyl chloride resin component contained in the partially crosslinked vinyl chloride resin (B) has an average degree of polymerization of 300 to 800. 4 The gel content contained in the partially crosslinked vinyl chloride resin (B) has the general formula (): (In the formula, R ₁ is a hydrogen atom or a methyl group, R ₂ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ₃ , R ₄
is a hydrogen atom, a methyl group, an ethyl group, -
Atom or group selected from CH ₂ CH ₂ COOH group, m,
n is an integer of 1 to 10, X represents a bromine atom, a chlorine atom, or a hydrogen atom), general formula (): (In the formula, R ₁ , R ₃ , R ₄ , and X are the same as above, l represents 0 or an integer from 1 to 20) or the general formula (): (In the formula, R ₁ , R ₂ , R ₃ , R ₄ , l, and X are the same as above, and i and j represent integers of 1 to 5.) The composition according to claim 1, 2 or 3, which is a vinyl chloride resin (B).