JPS5998152A - Vinyl chloride resin composition - Google Patents

Abstract

PURPOSE:The titled composition having extremely improved heat distortion resistance and processing characteristics without damaging characteristics of the resin of its own, by blending a vinyl chloride resin with a specific methyl methacrylate polymer. CONSTITUTION:At least 40-95pts.wt. vinyl chloride polymer comprising at least 80wt% vinyl chloride is blended with 60-5pts.wt. at least one methyl methacrylate polymer having 0.005-0.2l/g, preferably 0.3-0.06l/g reduced viscosity, comprising at least 75wt% methyl methacrylate. Ethyl acrylate or butyl acrylate is preferably as a copolymerizable monomer for the methyl mechacrylate copolymer.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vinyl chloride resin composition having excellent heat deformation resistance and processability.

Vinyl chloride has traditionally been inexpensive and flame-retardant.

Although it is a general-purpose resin that has many advantages such as chemical resistance, it also has the disadvantages of poor impact resistance, processability, and heat deformation resistance.

In order to improve the impact resistance, it has been developed to add a modifier such as a so-called MBS resin. Furthermore, as a modification of processability, addition of a high molecular weight acrylic polymer having a reduced viscosity of 0.3 or more has been carried out.

On the other hand, copolymers in which α-methylstyrene is copolymerized have been proposed for improving heat deformation resistance, as shown in Fi Patent Publication No. 45-24867 and Japanese Patent Publication No. 48-18101, but there are problems with processability. There still remains a problem.

Furthermore, since the high molecular weight acrylic polymer used to modify the processability has a high molecular weight, if the amount used is 5 parts by weight or more, the melt viscosity of the compounded composition will increase significantly, resulting in an increase in the load on the molding machine. Furthermore, it has the disadvantage of decreasing thermal stability.

In view of the current situation, the present inventors have arrived at the present invention as a result of intensive studies aimed at improving the heat deformation resistance and processability of vinyl chloride resin without impairing its properties. That is, the present invention uses 40 to 95 parts by weight of at least one type of vinyl chloride polymer containing at least 80% by weight of vinyl chloride and a reduced viscosity of 0.
．． A vinyl chloride resin composition having excellent heat deformation resistance and processability and comprising 60 to 5 parts by weight of at least one kind of methyl methacrylate polymer having a molecular weight of 0.005 to 0.2 and at least 75% by weight of methyl methacrylate. be.

The vinyl chloride polymer in the present invention is composed of at least 80% by weight of vinyl chloride, and is a vinyl chloride homopolymer or a vinyl chloride copolymer copolymerized with up to 20% by weight of other copolymerizable monomers. These homopolymers and copolymers can be used alone or in combination. Vinyl acetate is used as a copolymerizable monomer.

Ethylene, propylene, etc. are used, but the constituent content in the copolymer is up to 20% by weight, and if it exceeds 20% by weight, it is difficult to impart heat deformation resistance, which is the objective of the present invention, so it is preferable. do not have.

Next, the methyl methacrylate-based polymer in the present invention is composed of at least 75% by weight of methyl methacrylate and is copolymerized with methyl methacrylate homopolymer or with other copolymerizable monomers up to 25% by weight. It is a methyl methacrylate copolymer, and these homopolymers and copolymers can be used alone, or in combination.

On the other hand, this methyl methacrylate polymer has 12 as 11
The reduced viscosity of a solution dissolved in chloroform measured at 25°C is 0.005 to 0.2. Preferably 0.03~0
．． It is necessary that the reduced viscosity is within the range of 0.06 and the reduced viscosity is 0.06.
If it is less than 005, it will be difficult to impart heat deformation resistance, which is the objective of the present invention, and thus it is unskillful. Also, the reduced viscosity is 0
．． If it exceeds 2, the load when molding the resulting resin composition becomes large and processability decreases, which is not preferable.

As the copolymerizable monomer of the methyl methacrylate copolymer, acrylic acid alkyl ester having an alkyl group having 1 to 8 carbon atoms, styrene, α-methylstyrene, acrylonitrile, etc. can be used, and ethyl acrylate, Butyl acrylate and the like are preferred. The constituent content of the copolymerizable monomer in the copolymer is up to 25% by weight, and if it exceeds 25% by weight, it becomes difficult to impart heat deformation resistance, which is not preferred. The content of the copolymerizable monomer is preferably less than 10% by weight.

The vinyl chloride resin composition of the present invention contains 40 to 95 parts by weight of at least seven of the above vinyl chloride polymers and 60 to 5 parts by weight of at least one of the methyl methacrylate polymers. If the blending amount of the methyl methacrylate polymer is less than 5 parts by weight, the effect of imparting heat deformation resistance will not be sufficient, and if it exceeds 60 parts by weight, the vinyl chloride polymer will have poor flame retardancy, chemical resistance, etc. This is not preferable because the characteristics originally possessed by the polymer are impaired.

The feature of the present invention is that the methyl methacrylate-based polymer used in the present invention does not have to worry about increasing the melt viscosity of the blended resin composition compared to conventionally used processability modifiers for high molecular weight acrylic polymers. Because of this, it is possible to mix in the high addition amount as described above, and it has been possible to significantly improve processability such as vacuum formability in addition to heat deformation resistance.

The vinyl chloride resin composition of the present invention can be used as a molding material in the field of injection molding of rain gutters and pipe joints, and in the field of vacuum forming of sheets, plates, and the like.

A heat stabilizer, a light stabilizer, a lubricant, a filler, etc. can be added to the vinyl chloride resin composition of the present invention, if necessary.

The present invention will be specifically explained below using Examples.

In the Examples and Comparative Examples, all "parts" are 1 part by weight.

Examples 1-5. Comparative Examples 1 to 2 250 parts of distilled water, 1.0 part of potassium oleate, 5 parts of potassium persulfate, and the respective amounts of the monomers and ordodecyl mercaptan shown in Table 1 were placed in a stirred root cell reaction vessel. and polymerized at 60°C for 5 hours. After the reaction was completed, the resulting latex was coagulated, washed, and dried to obtain various methyl methacrylate polymers.

30 parts of the various methyl methacrylate polymers, 70 parts of polyvinyl chloride (average degree of polymerization 800), 2.0 parts of diptyltin mercaptide, and 0.5 parts of butyl stearate. 0.5 part of montan wax is blended and then formed into various sheets of 5 thicknesses using a 40 mm ψ extruder.

Table 1 shows the results of evaluating the heat resistance and processability of the various sheets obtained. Processability is the load (A) of a 40 cylinder φ extruder
Indicate by . The elongation of the sheet at 100° C. was measured as a measure of vacuum formability. The results are shown in Table 1. A high elongation indicates excellent vacuum formability.

Examples 6-8. Comparative Examples 3 to 4 Each part of the methyl methacrylate homopolymer obtained in Example 1 shown in Table 2 was blended with polyvinyl chloride, and 100% of each
Department. Table 2 shows the properties of these formulations determined by the method shown in Table 1.

As in Example 1, the formulation contained 2.0 parts of diptyltin mercaptide, 0.5 parts of butyl stearate, and 0.5 parts of montan wax.

Table 2 Procedural amendment Mr. Kazuo Wakasugi, Commissioner of the Patent Office 1.Display of the incident Patent application No. 196588, 1988 2. Name of the invention Vinyl chloride resin composition 3. Person who makes corrections Relationship to the incident: Patent applicant 2-3-19 Kyobashi, Chuo-ku, Tokyo (603) Mitsubishi Rayon Co., Ltd. President and Director Akio Kawasaki 4. Deputy manager 2-3-19 Kyobashi, Chuo-ku, Tokyo and “Detailed Description of the Invention” column. 7. Contents of correction (The scope of the 13% claim is corrected as shown in the attached sheet.

(2) Replace [0, 3j in the second line of page 2 of the specification with “0.
Corrected to 3M/J.

(3) Page 3, line 1, [0,2J r 0.21/
P Correct to J.

(4) 4th negative 7th line [0,2J r 0.21/
l Correct to J.

(5) On page 4, line 8, “0.06J is ro, 061
//” to be corrected.

(6) [0,o05J on page 4, line 9] rO,00
51/p Corrected to J.

(7) l-0, 2J on page 4, line 11 of the same page is r O,
Corrected to 211/f J.

(8) “Eau de decyl” on page 6, line 17 of the same page is changed to “
Corrected to "t-dodecyl".

(9) “Nuteari” on page 7, line 4 of the same page was changed to “Steari J”
K Correct.

1) (10) "ηsp/c" in Table 1 on page 8 of the same page is changed to [ηQ/c
(It//) Correct to J.

“Claims

Claims (1)

[Claims] A methyl methacrylate system consisting of 40 to 95 parts by weight of at least one type of vinyl chloride polymer comprising at least 80% by weight of vinyl chloride, a reduced viscosity of 0.005 to 0.2, and at least 75% by weight comprising methyl methacrylate. A vinyl chloride resin composition having excellent heat deformation resistance and processability and comprising 60 to 5 parts by weight of at least one kind of polymer.