JPS5998153A - Vinyl chloride resin composition - Google Patents

Abstract

PURPOSE:To improve weather resistance, heat resistance, impact resistance, and processing characteristics harmoniously, by blending a vinyl chloride resin with a specific methyl methacrylate polymer and a graft polymer containing acrylic rubber. CONSTITUTION:(A) 40-80pts.wt. vinyl chloride resin comprising >=70wt% vinyl chloride component is blended with (B) 5-40pts.wt. methyl methacrylate polymer consisting of 75-100wt% methyl methacrylate component and 25-0wt% another copolymerizable monomer component (preferably <=10wt% especially ethyl acrylate or butyl acrylate), having 0.005-0.2l/g, preferably 0.03-0.08l/g reduced viscosity, and (C) 5-30pts.wt. (10-25pts.wt. graft copolymer is most efficient and especially preferable) graft copolymer obtained by copolymerizing 70-20wt% two or more compounds selected from an acrylic acid alkyl ester, methacrylic acid alkyl ester, aromatic vinyl compound, and cyanide compound in the presence of 30-80wt% acrylic rubber.

Description

[Detailed description of the invention] The present invention relates to a vinyl chloride resin composition.

Vinyl chloride resin is widely used as a general-purpose resin, but when used alone, it has poor impact resistance, heat deformation resistance,9 for example, formability of gate marks seen during injection molding, and secondary processability such as vacuum forming. It is not always possible to obtain satisfactory characteristics. Various additives have been proposed for modifying these. A typical example is MBS resin. Regarding heat resistance, it has also been proposed to use a resin having a high softening temperature and containing α-methylstyrene as a main component. Furthermore, with regard to processability, acrylic polymers or copolymers with a high degree of polymerization and having a reduced viscosity of α3 or higher, which are called processing aids, are added.

Although the purpose of seaming can be achieved by applying these various methods, even if two or three of these methods are used at the same time, for example, heat resistance modifiers may deteriorate various physical properties including impact resistance. It is difficult to achieve balanced performance in everything. Additionally, impact modifiers using butadiene lose strength over time when used outdoors.

It is unusable because it causes discoloration.

Furthermore, no suitable method for improving secondary moldability has yet been found.

In view of the current situation, the present inventors conducted intensive studies to obtain a resin composition that improves the disadvantages of vinyl chloride resins in a well-balanced manner.As a result, they developed a graft copolymer using a specific methyl methacrylate polymer and acrylic rubber as rubber sources. The present invention was achieved by discovering that the above object can be achieved by blending it into a vinyl chloride resin in a specific range.

That is, the present invention comprises 40 to 80 parts by weight of a vinyl chloride resin (A) composed of 70% by weight or more of a vinyl chloride component, 75 to 100% by weight of a methyl methacrylate component, and 25 to 0 parts by weight of other copolymerizable monomer components. % and has a reduced viscosity of 0.005 to 0.2, 5 to 40 parts by weight of methyl methacrylate polymer (B), and 30 to 40 parts by weight of acrylic rubber.
A graft copolymer obtained by copolymerizing 70 to 20% by weight of at least two compounds selected from the group of acrylic acid alkyl esters, methacrylic acid alkyl esters, aromatic vinyl compounds, and cyanide compounds in the presence of 80% by weight. (C) A vinyl chloride resin composition containing 5 to 30 parts by weight and having excellent weather resistance, heat resistance, impact resistance, and processability.

The vinyl chloride resin (A) in the present invention is a homopolymer or copolymer composed of 70 or more vinyl chloride components, and can be used alone or in combination. Examples of copolymerization components include ethylene, propylene, vinyl acetate, and the like. When the copolymerization component exceeds 30% by weight, the heat deformation temperature decreases significantly, and it becomes difficult to impart heat deformation resistance, which is the object of the present invention.

Next, the methyl methacrylate polymer (B
) is a methyl methacrylate homopolymer or methyl methacrylate copolymer composed of 75 to 100% by weight of a methyl methacrylate component and 25 to 0% by weight of other copolymerizable monomer components, and these homopolymers and copolymers are The polymers can be used alone or in combination.

In addition, this methyl methacrylate polymer (B) is part 1
It is necessary that the reduced viscosity of a solution prepared by dissolving 2 in 1 ton of chloroform at 25°C is in the range of 0005 to 0.2, and if the reduced viscosity is less than o, o o s, the heat resistance will be maintained. If the content exceeds 0.2 parts by weight, which is within the scope of the present invention, the load increases during extrusion molding, making processing difficult. Considering normal molding means, the reduced viscosity of polymer (B) is 0.0
A range of 3 to 008 is preferred.

Other copolymerizable monomer components constituting the polymer (B) include acrylic acid alkyl esters having an alkyl group having 1 to 8 carbon atoms.

Styrene, α-methylstyrene, acrylonitrile, etc. can be used, and it is particularly preferable to use ethyl acrylate or butyl acrylate in an amount of 10% by weight or less. If the copolymerizable monomer component exceeds 25% by weight, it is generally difficult to impart heat resistance, which is not preferred.

Furthermore, the graft copolymer (C) in the present invention imparts impact resistance to the resin composition of the present invention. The acrylic rubber constituting the graft copolymer (C) provides superior weather resistance compared to diene rubber. However, depending on the application, 4 in acrylic rubber may be necessary.
It is possible to replace the 0-layered rubber or less with a co-yoke diene rubber, and such a case is also included in the scope of the acrylic rubber in the present invention. It is obtained from acrylic rubber and an acrylic acid alkyl ester mainly having 1 to 8 carbon atoms. The graft copolymer (C) is an acrylic acid alkyl ester in the presence of 30 to 80% by weight of such acrylic rubber.

It is obtained by copolymerizing 70 to 20% by weight of at least two compounds selected from the group of methacrylic acid alkyl esters, aromatic vinyl compounds, and cyanide compounds. Here, the acrylic acid alkyl ester for graft copolymerization is one having an alkyl group having 1 to 8 carbon atoms. The methacrylic acid alkyl ester is one having an alkyl group having 1 to 4 carbon atoms. Examples of the aromatic vinyl compound include styrene, α-methylstyrene, vinyltoluene, a-methylvinyltoluene, and the like. Furthermore, examples of the cyanide compound include acrylonitrile and methacrylatetrile. In the present invention, among these compounds, methyl methacrylate, butyl acrylate, styrene, etc. are commonly used. If the amount of the monomer for graft copolymerization exceeds 70% by weight, the elastic component is insufficient and satisfactory impact resistance cannot be obtained.2. If it is less than 20% by weight, the compatibility with the vinyl chloride resin component (A) is insufficient, interfacial peeling occurs, and sufficient impact resistance cannot be obtained.

The vinyl chloride resin composition of the present invention contains 40 to 80 parts by weight of the vinyl chloride resin (A), 5 to 40 parts by weight of the methyl methacrylate polymer (B), and 5 to 40 parts by weight of the graft copolymer (0). 30 parts by weight, and the total amount of (A) to (C) was 100 parts by weight. The vinyl chloride resin (A) is the pace of the resin composition, and if the amount is less than 40 parts by weight, the inherent properties of the vinyl chloride resin, such as flame retardancy and chemical resistance, will be significantly reduced. do. More preferably, it is used in an amount of 60 parts by weight or more. In addition, the methyl methacrylate polymer (B) is important for heat resistance, mechanical rigidity, moldability, and secondary formability, and if the amount is less than 5 parts by weight, these performance imparting effects will be insufficient. . Moreover, when blending in an amount exceeding 40 parts by weight, the impact resistance imparting effect of the graft copolymer (C) component is impaired, which is not preferable. Furthermore, the graft copolymer (C) is treated in the same way as a conventional impact modifier; if it is less than 5 parts by weight, its effect is poor, and if it exceeds 30 parts by weight, it forms a continuous layer, This is not preferable since the impact resistance is rather reduced. In the present invention, the amount of the graft copolymer (C) blended is 10 to 25 parts by weight, which is most efficient and particularly preferred.

The vinyl chloride resin composition of the present invention overcomes the drawbacks of ordinary vinyl chloride resins by blending a low-viscosity methyl methacrylate polymer and a graft polymer, which is an impact modifier, into a vinyl chloride resin. It is a product that has been able to improve the heat resistance 2 mechanical properties, molding processability, weather resistance, and impact resistance in a well-balanced manner, and the secondary formability such as vacuum formability is also improved by using a large amount of methyl methacrylate polymer. Significant improvement is achieved by adding

The vinyl chloride resin composition of the present invention is used as a sheet.

It can be used for plates, irregularly molded products, and injection molded products, and further, by taking advantage of its excellent weather resistance, it can also be used for outdoor and indoor housing-related parts, furniture, containers, etc. Extrusion is the molding method.

Conventional forming methods such as rolling, injection etc. can be used.

Heat stabilizers, light stabilizers, lubricants, fillers, dyes and pigments, and even small amounts of plasticizers 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 "parts by weight."

Example 1. Comparative examples 1 to 3 65 parts of polyvinyl chloride with an average degree of polymerization of 700.

95% by weight of methyl methacrylate with reduced viscosity of 0.05
and 20 parts of methyl methacrylate-ethyl acrylate copolymer composed of 5% by weight of ethyl acrylate, and 20% by weight of butyl acrylate and 10% by weight of methyl methacrylate in the presence of 70% by weight of butyl acrylate rubber. Graft copolymer 15
2 parts of butyltin mercaptide, 1 part of butyl stearate
A mixture of 1 part and 1 part of monk acid wax was extruded using a 4 part me single screw extruder to obtain a sheet with a thickness of 3 smoke. Table 1 shows the results of various tests conducted on this sheet.

Weather resistance was measured by impact strength after accelerated exposure using a Sunshine Weatherometer. In addition, as a guide for secondary formability, a vacuum forming machine was used to measure the inner diameter of 90 mg (i.
The moldable depth was evaluated when molded at 140'C and 6703HS' using a model wooden mold with a taper toward the bottom of r and a variable depth.

Comparative Example 1 MBs resin (trade name Metaprene Cj225) composed of diene rubber instead of the graft copolymer of Example 1 was used.
, manufactured by Mitsubishi Rayon Co., Ltd.) was used, and the same formulation as in Example 1 was used, molded, and tested and evaluated. The results are also shown in Table 1.

Comparative Example 2 ABS resin (trade name Diabella) composed of diene rubber instead of the graft copolymer of Example 1 ABS 3001. The same formulation as in Example 1 was carried out, except that a material (manufactured by Mitsubishi Rayon Co., Ltd.) was used, molded, and tested and evaluated. The results are also shown in Table 1.

Comparative Example 3 4 parts of methyl methacrylate-ethyl acrylate copolymer composed of 95% by weight of methyl methacrylate and 5% by weight of ethyl acrylate with a reduced viscosity of 0.3, 10 parts of the graft copolymer used in Example 1, Example A sheet containing 86 parts of the polyvinyl chloride used in Example 1 and molded in the same manner as in Example 1 was tested and evaluated. The results are also shown in Table 1.

Table 1 Procedural amendment 1.Display of the incident Patent Application No. 196589/1989 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. Agent 2-3-19 Kyobashi, Chuo-ku, Tokyo Mitsubishi Rayon Co., Ltd. (6949) Patent attorney Toshio Yoshizawa “Detailed description of the invention” column 7. Contents of correction (1) Amend the scope of claims as shown in the attached sheet.

(2) r O, 3J on page 2, line 11 of the specification is “o,
31, # Correct to J.

(3) Page 3, line 16, “o, 2J to r O,
Corrected to 21/P J.

(4) ro, zJ in the second line of page 5 is r O, 21/
Correct to P j.

(5) [0,005J and “0.
2 J to r 0.0051t/l J and r respectively
O, 21, # Corrected to J.

(6) “0.08J is ro, os1” on page 5, line 9.
7# JK correct.

(7) l'-0,05J in the second line of page 10 is ro,
Corrected to 05It/l J.

, (8) r O, 3J on page 11, line 16 of the same page is "0.
3//P”.

2. Scope of claims

Claims (1)

[Claims] Vinyl chloride resin body composed of 70% by weight or more of vinyl chloride component) 40 to 80 parts by weight, 70 to 20% by weight of methyl methacrylate component and other copolymerizable monomer components 2
5 to 0% by weight, and its reduced viscosity is o,
o o s ~ 0.2 methyl methacrylate polymer (B) 5-40 parts by weight, acrylic rubber 30-80% by weight
At least two compounds selected from the group of acrylic acid alkyl esters, methacrylic acid alkyl esters, aromatic vinyl compounds and cyanide compounds 70-2 in the presence of
Graft copolymer obtained by copolymerizing 0% by weight (
C) A vinyl chloride resin composition containing 5 to 30 parts by weight and having excellent weather resistance, heat resistance, impact resistance, and processability.