JPH11269295A - Chlorinated vinyl chloride based resin composition for foaming - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chlorinated vinyl chloride based resin composition for foaming good in foamability and moldability without using any lead based stabilizers and tin based stabilizers. SOLUTION: This chlorinated vinyl chloride based resin composition for foaming comprises 100 pts.wt. chlorinated vinyl chloride resin having an average chlorine content of 60-72 wt.% alone or its mixture of a vinyl chloride resin; 0.5-6 pts.wt. at least one stabilizer selected from silicate salts of a group II or III metal, complexes of silicic acid and an oxide of said metal, complexes of silicic acid and a hydroxide of said metal, complexes of silicic acid and a carbonate of said metal, hydrotalcites and zeolites; 3-20 pts.wt. methacrylic ester based resin; and 0.1-3 pts.wt. decomposition type organic blowing agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a chlorinated vinyl chloride resin composition having heat resistance and excellent foamability.

[0002]

2. Description of the Related Art Chlorinated vinyl chloride resin (hereinafter referred to as CPV)
C) is generally a vinyl chloride resin (hereinafter referred to as PVC).
Chlorination). CPVC retains flame-retardant and chemical-resistant properties, which are said to be advantages of PVC, and
C is expected to be used in a wide range of applications because it has improved the low heat resistance temperature which is said to be a disadvantage of C. On the other hand, PVC has a major drawback that it cannot be used at temperatures of 60 to 70 ° C. or higher because of its low heat deformation temperature. On the other hand, the heat deformation temperature of CPVC is higher by 20 to 40 ° C. than that of PVC, and the heat resistance, which is a drawback of PVC, is improved. Therefore, the heat resistance is excellent in the case of using a foam molded article.

[0003] Conventionally, as a stabilizer for a foamed molded article, a lead compound or a tin compound has been mainly used. However, recently there has been a trend toward de-leading, and the use of chlorinated vinyl chloride resin has been hindered. It was difficult to obtain all the foamed molded articles.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and uses CPVC, does not use a lead-based stabilizer or a tin-based stabilizer, and has good foamability and moldability. The present invention provides a CPVC composition for foaming.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a method for producing a single CPVC or PVC having an average chlorine content of 60 to 72% by weight.
At least one of a silicate of a metal of Group II or Group III of the periodic table, a composite of silicic acid and an oxide of the metal, a hydrotalcite, or a zeolite Characterized in that the stabilizer comprises 0.5 to 6 parts by weight of a stabilizer, 3 to 20 parts by weight of a polymethyl methacrylate resin, and 0.1 to 3 parts by weight of a decomposable organic foaming agent.

The average degree of polymerization of CPVC used in the present invention is 500 to 14 as an average degree of polymerization of PVC before chlorination.
00 is preferred. If the average degree of polymerization is less than 500, the impact strength is reduced, and if it exceeds 1400, the melt fluidity is reduced, and molding becomes difficult.

The average chlorine content of CPVC is 60 to
Limited to 72% by weight. 60% by weight average chlorine content
If it is less than 30, heat resistance is reduced and deformation is apt to occur, and
If the content exceeds% by weight, the fluidity is greatly reduced, and molding becomes difficult. Similarly, when used in combination with PVC, it is limited to the range of 60 to 72% by weight.

The metal used in the present invention may be Mg, A
l, Ca, or Zn is preferred.

Examples of the silicate include alkaline earth metal silicates such as magnesium silicate, calcium silicate, barium silicate and strontium silicate; Group IIb metal salts of silicic acid such as zinc silicate; Group IIIb metal salts of silicic acid, such as aluminum silicate, may be used alone or in combination of two or more. Among these silicates, magnesium silicate, calcium silicate, zinc silicate and aluminum silicate are preferably used as a non-lead-based non-toxic stabilizer.

Examples of the composite of silicic acid and the oxide, hydroxide, or carbonate of the metal include, but are not limited to, the following.

Examples of the oxides and hydroxides of Group II or Group II metals in the above periodic table include calcium oxide, calcium hydroxide, magnesium oxide, magnesium hydroxide, zinc oxide, zinc hydroxide and the like. No.

Group II or III of the periodic table
Examples of the carbonate with a group metal include basic calcium carbonate, calcium carbonate, basic magnesium carbonate, magnesium carbonate, basic zinc carbonate, and other bicarbonates such as calcium bicarbonate and magnesium bicarbonate.

The amount of the stabilizer is limited to 0.5 to 6 parts by weight based on 100 parts by weight of the resin component. If the amount is less than 0.5 part by weight, the thermal stability of the CPVC composition is poor, and if it exceeds 6 parts by weight, the melt fluidity of the CPVC is reduced and molding becomes difficult.

In the present invention, a methacrylic ester resin is added to CPVC. As the methacrylic acid ester-based resin, a homopolymer of methacrylic acid ester or a copolymer of methacrylic acid ester and another monomer can be used. As the methacrylate, methyl methacrylate, ethyl methacrylate and the like are used. As other monomers, ethyl acrylate, acrylonitrile and the like are used. In the above-mentioned copolymer, it is preferable that the ratio of the methacrylic acid ester is larger than that of the other monomers.

The methacrylate resin is CPVC
The amount is limited to 3 to 20 parts by weight, preferably 5 to 13 parts by weight, per 100 parts by weight. When the methacrylic acid ester-based resin is added at such a ratio, the CPVC has a melt viscosity suitable for foaming, and foams well to generate small bubbles, and the bubbles once formed cannot be easily collapsed.

As the decomposable organic foaming agent used in the present invention, a thermally decomposable organic foaming agent such as azodicarbonamide is used. The number of parts to be added is limited to 0.1 to 3 parts by weight, preferably 0.1 to 0.5 parts by weight, of the pyrolytic organic blowing agent based on 100 parts by weight of CPVC.

The composition according to the present invention comprises calcium carbonate, talc, clay, as fillers in addition to those described above.
Silica and the like can be added. As the filler, fine particles are preferable, and those having an average particle diameter of 3 μm or less are particularly preferable.

In addition, the composition according to the present invention comprises CP
An impact modifier, a lubricant, a plasticizer, an antioxidant, an ultraviolet absorber, a colorant, a flame retardant, and the like generally used in VC processing can be added.

In order to prepare the composition according to the present invention, the above-mentioned compound is uniformly mixed with a super mixer to obtain a compounded powder. Further, in order to obtain a shape that can be easily extruded, it is preferable to form a pellet with a twin screw extruder or the like.

The molded product according to the present invention is obtained by putting a compounded powder or a pelletized composition into an extruder and melting it to obtain a foamed molded product. The molded article obtained from the CPVC composition of the present invention can be used for various vinyl chloride foamed products, for example, as materials for peripheral edges of houses, handrails, curtain rails, window frames, and the like.

The CPVC composition of the present invention is obtained by an extrusion method,
Although injection molding is possible, extrusion molding is more suitable. In order to extrude the CPVC composition of the present invention, for example, a mixture obtained by uniformly dispersing the composition by a supermixer, or a pellet obtained by supplying the mixture to an extruder and cutting the mixture with a pelletizer, is used. What is necessary is just to shape | mold.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

(Examples 1 to 6, Comparative Examples 1 to 4) A resin composition obtained by uniformly mixing the components in the amounts shown in Table 1 with a super mixer was measured at a cylinder temperature of (C1: 14).
0 ° C, C2: 150 ° C, C3: 160 ° C, C4: 165
° C), adapter-temperature 160 ° C, die temperature 15
The mixture was fed to a 30 mm biaxial extruder set at 5 ° C. and cut with a pelletizer to obtain pellets. Next, the pellets were heated at a barrel temperature (B1: 150 ° C, B2: 160 ° C, B3: 170) using a 65 mm single extruder (L / D = 22, full flight screw, compression ratio = 3.0).
° C), and set the die temperature to (DH: 175 ° C,
(D1: 175 ° C., D2: 185 ° C.) to obtain a flat molded body.

The following raw materials were used as shown in Table 1. * 1 CPVC: manufactured by Tokuyama Sekisui Industry Co., Ltd. (raw material PVC polymerization degree 8
00, chlorine content 64% by weight) * 2 CPVC: manufactured by Tokuyama Sekisui Industry Co., Ltd. (raw material PVC polymerization degree 8
00, chlorine content 66.5% by weight) PVC: TS-800E manufactured by Tokuyama Sekisui Industry Co., Ltd. (polymerization degree 80
0) Calcium silicate: Magnesium silicate manufactured by Mizusawa Chemical Co., Ltd. Octyltin mercapto manufactured by Mizusawa Chemical Co., Ltd .: Tribasic lead sulfate manufactured by Sankyo Chemical Co., Ltd .: Methyl methacrylate resin manufactured by Sakai Chemical Co., Ltd .: manufactured by Mitsubishi Rayon Co., Ltd.
-530A) Azodicarbonamide: Eiwa Chemical Co., Ltd. (product name AC # 1) Filler: Shiraishi Industry Co., Ltd. (product name CCR) Lubricant: ester wax

(1) Heat deformation temperature The above resin composition was kneaded with a 200 ° C. roll for 3 minutes, and then preheated to a 200 ° C. press for 4 minutes, pressurized for 5 minutes, and surface pressure of 75 kg / cm ² . Create a 6.4mm thick plate,
It was measured according to IS K 7207. (2) Specific Gravity The obtained molded body was measured in accordance with JIS K 7112 A method (substitution method in water). (3) Cell Size The molded article of (1) was placed in liquid nitrogen, cut by applying an impact, and the size of the cell that appeared on the obtained cross section was measured by a scanning electron microscope. (4) Surface properties The molded product of (1) was visually observed and ranked as follows. ◎: Very good surface ○: Good △: Slight wavy
×: Large undulation

[0026]

[Table 1]

[0027]

The CPVC composition of the present invention is constituted as described above, and is comparable to a lead-based stabilizer by using a silicate of Group II or Group III of the periodic table as a stabilizer. Heat resistance is obtained, and a melt viscosity suitable for foaming is obtained by further adding a methacrylic acid ester. Foamability and moldability are improved by using an organic foaming agent such as azodicarbonamide.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 33:10)

Claims (2)

[Claims] 1. A chlorinated vinyl chloride resin having an average chlorine content of 60 to 72% by weight or 100 parts by weight of a mixture with a vinyl chloride resin, Group II or II of the periodic table
Group I metal silicates, composites of silicic acid and said metal oxides, composites of silicic acid and said metal hydroxides, composites of silicic acid and said metal carbonates, hydrotals 0.5 to 6 parts by weight of at least one or more stabilizers among sites or zeolites are added to a methacrylate resin 3 to
A chlorinated vinyl chloride resin composition for foaming, comprising 20 parts by weight and 0.1 to 3 parts by weight of a decomposable organic foaming agent. 2. The group II or III of the periodic table
The chlorinated vinyl chloride resin composition for foaming according to claim 1, wherein the group metal is Mg, Al, Ca or Zn.