JPH11255990A - Thermoplastic elastomer resin composition, its extruded product and window frame - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a low-foaming thermoplastic elastomer resin composition excellent in moldability and sliding properties and provide its low foaming extruded products. SOLUTION: This thermoplastic elastomer resin composition contains a vinyl chloride-based resin, a plasticizer and thermally expanding microcapsules, and further, an acrylonitrile-butadiene rubber. The extruded products are produced by extruding the resin composition. Gaskets for window frames consist of extruded formed products. The window frame has the gaskets.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic elastomer resin composition, particularly to a molded article and a low-foaming thermoplastic elastomer resin composition having excellent slidability, and a low-foaming extrusion molded article thereof.

[0002]

2. Description of the Related Art Conventionally, foamed molded articles of a soft vinyl chloride resin have been used for the purpose of reducing the weight, improving sound insulation, heat insulating properties, sealing properties, and improving the softness (softness) of the product. in use. In recent years, the use of a foamed molded article of a soft vinyl chloride resin composition has been studied for the same purpose in fields such as window frames and weather strips for automobiles. In order to smooth the opening and closing of the resin, it is required to reduce the coefficient of friction and to impart slidability to the resin.

In order to obtain a foamed molded article of a soft vinyl chloride resin, for example, Japanese Patent Publication No. 7-74286 discloses a vinyl chloride resin, a methyl methacrylate copolymer, a plasticizer,
After pelletizing a soft vinyl chloride resin composition containing a decomposable blowing agent such as azodicarbonamide or N, N'-dinitrosopentamethylenetetramine, a molded product is obtained by injection molding, extrusion molding, or the like. A method has been proposed. Also, Japanese Patent Publication No. 7-107106 discloses vinyl chloride resin, acrylonitrile-butadiene rubber, methyl methacrylate copolymer, and decomposition type such as azodicarbonamide and N, N'-dinitrosopentamethylenetetramine. A method has been proposed in which after a soft vinyl chloride-based resin composition containing a foaming agent is pelletized, a molded article is obtained by injection molding, extrusion molding, or the like.

[0004] In the molded article of the foamed soft vinyl chloride resin composition using these decomposable foaming agents, a smooth surface called a skin layer is formed on the surface of the molded article in order to obtain independent dense and uniform foamed cells. A method of trapping the foam cells therein is adopted. Since this skin layer is smooth, it has poor slidability, and when a product is assembled and used, there is a problem that opening and closing of a window becomes poor.

As methods for imparting slidability, a method of roughening the surface of a smooth molded article, a method of using a lubricant, and the like are generally known.

[0006] As a method of roughening the surface of the molded article to impart slidability, there is a method of using a filler such as calcium carbonate or a method of using a partially cross-linked vinyl chloride resin as a vinyl chloride resin.

However, in order to improve the slidability of a molded article of a resin composition using a decomposable foaming agent in a soft vinyl chloride-based resin to improve the sliding property, a filler such as calcium carbonate must be used. Must be used in large quantities. For this reason, there have been problems that the moldability is significantly impaired, and that it is difficult to adjust the viscosity of the resin necessary for maintaining dense and uniform cells, and it is difficult to obtain a good foamed molded article. In addition, the method of using a large amount of the filler has a problem that it is contrary to the original purpose of using the foamed molded article, that is, the weight reduction.

On the other hand, similarly, when a partially crosslinked vinyl chloride resin is used, there is also a problem that it is difficult to adjust the viscosity of the resin necessary to maintain a dense and uniform cell, and it is difficult to obtain a good foamed molded article. Was.

Further, as a method of improving the slidability by using a lubricant, a method of imparting slidability by adding a lubricant such as a hydrocarbon wax, a fatty acid ester, a fatty acid amide or a higher alcohol, or the like, As described in JP-A-6-263923 and JP-A-6-263924, a method of adding a silicone polymer or a fluororesin is generally known.

However, in the method of imparting slidability by adding a lubricant, a large amount of a lubricant must be added in order to obtain sufficient slidability, and a soft vinyl chloride resin composition containing a large amount of a lubricant is required. Extrusion molding does not apply sufficient shear in the molding machine, resulting in molding failure, bleeding after molding, poor appearance and poor adhesion to other components, and desorption of lubricant components resulting in friction. There were problems such as the resistance increasing over time. There is a problem that the method of adding a silicon polymer or a fluororesin is economically disadvantageous.

[0011]

DISCLOSURE OF THE INVENTION The present invention is intended to reduce the weight, improve the sound insulation, the heat insulation, the sealing performance, and the softness of the product, which cannot be achieved by the conventional foamed molding containing a decomposable foaming agent. The present invention has been made to solve the problem of improving the slidability by further reducing the coefficient of friction of the molded article.

[0012]

That is, the present invention is a thermoplastic elastomer resin composition containing a vinyl chloride resin, a plasticizer and a heat-expandable microcapsule. It is a thermoplastic elastomer resin composition containing acrylonitrile-butadiene rubber and heat-expandable microcapsules. And an extruded product obtained by extruding the thermoplastic elastomer composition, wherein the extruded product is the extruded product which is a window frame gasket, and a window formed by extruding the thermoplastic elastomer composition. It is a window frame having a frame gasket.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below.

The vinyl chloride resin used in the present invention refers to a vinyl chloride resin obtained by homopolymerizing a vinyl chloride monomer or a vinyl chloride copolymer containing 50% or more of vinyl chloride and containing a gel component. A partially cross-linked vinyl chloride resin may be used, and any conventionally known vinyl chloride resin may be used as long as it is compatible with them. Copolymer components other than vinyl chloride of the vinyl chloride copolymer containing at least 50% vinyl chloride include vinyl esters such as vinyl acetate and vinyl stearate, olefins such as ethylene and propylene, and (meth) acrylic acid. (Meth) acrylates such as butyl and 2-ethylhexyl (meth) acrylate, maleates such as butyl maleate and octyl maleate, and fumaric esters such as butyl fumarate and octyl fumarate And the like, but are not limited thereto. Two or more of these components other than vinyl chloride may be used in combination.

As the partially crosslinked vinyl chloride resin containing a gel component, diallyl phthalate,
Diallyl maleate, polyethylene glycol di (meth)
Examples include, but are not limited to, resins obtained by copolymerization using polyfunctional compounds such as acrylates and 1,2-polybutadienes. These vinyl chloride resins may be used alone or as a mixture of two or more as necessary. Among these vinyl chloride-based resins, a vinyl chloride-based resin containing no gel component is preferable because the mechanical strength of the molded article is hardly reduced.

The vinyl chloride resin is JIS K6721.
The average degree of polymerization measured in the above is preferably 500 to 4500, more preferably 700 to 3000. If the average degree of polymerization is less than 500, the mechanical strength of the molded article obtained may be extremely poor, and the average degree of polymerization may be less than 450.
If it exceeds 0, it is difficult to sufficiently gel during molding, and the moldability may be deteriorated.

The plasticizer used in the present invention is not particularly limited as long as it is used for the production of a soft molded article of a vinyl chloride resin. Phthalates, trimellites, pyromellites, fatty acids Group-based diesters, glycol esters, fatty acid esters, phosphate esters and citrate ester-based plasticizers, epoxy-based plasticizers such as epoxidized soybean oil, and polyester-based plasticizers. Of these, phthalic acid esters are preferred in terms of economy.

The amount of the plasticizer used is 10
30 to 200 parts by weight, preferably 50 to 50 parts by weight, per 0 parts by weight.
150 parts by weight is more preferred. If the amount is less than 30 parts, the product obtained by molding may lack a soft feeling.
If the amount exceeds the weight part, it is difficult to absorb the resin into the vinyl chloride resin at the time of dry-up, and the dry-up operation itself may become impossible, and the workability and moldability may be reduced.

The heat-expandable microcapsules used in the present invention have an outer shell made of a thermoplastic polymer such as vinylidene chloride or a vinylidene chloride-acrylonitrile copolymer, and contain a hydrocarbon such as isobutane or isopentane inside the shell. It means that the internal hydrocarbon is gasified during heating. EXPA as the thermal expansion type microcapsule
NCEL (092) DU120 or EXPANCEL (0
91) DE80 and the like, but are not limited thereto.

The amount of the heat-expandable microcapsules is preferably 1 to 30 parts by weight, more preferably 1.5 to 15 parts by weight, based on 100 parts by weight of the vinyl chloride resin. If the amount is less than 1 part by weight, the expansion ratio becomes extremely small, and the effect of improving the slidability may be small. If the amount exceeds 30 parts by weight, the moldability may be reduced, or the foam may be excessively foamed and the appearance may be significantly impaired. .

In the present invention, in order to improve the soft feeling and rubber elasticity of the molded article, and to restore the shape when released after use in a pressurized use environment to the shape before use (expressed as the following). Acrylonitrile-butadiene rubber (hereinafter N
BR) can be used.

The amount of bound acrylonitrile of NBR used in the present invention is preferably 20 to 45% by weight. 20% by weight
If the amount is less than the above, the compatibility with the vinyl chloride resin may be deteriorated. If the amount exceeds 45% by weight, the molded product may lack the soft feeling and the rubber elasticity. The NBR to be used can be either an uncrosslinked type or a partially crosslinked type. However, the partially crosslinked type is preferable in terms of excellent moldability and less set.

The amount of NBR used is 10
10 to 250 parts by weight, preferably 50 parts by weight,
~ 200 parts by weight is more preferred. If the amount is less than 10 parts by weight, the product obtained by molding may have great settling when used under a pressurized use environment. This can be evaluated by measuring the compression set of a material, and a material having a large set under a pressurized use environment has a large compression set. If the NBR exceeds 250 parts by weight, molding may be difficult or the expansion ratio may not be increased.

In the present invention, fillers, heat stabilizers, lubricants, processing aids, ultraviolet absorbers, antioxidants, pigments, flame retardants, etc., which are used in ordinary vinyl chloride, may be used, if necessary. it can.

Further, in the present invention, carbon black, calcium carbonate, titanium oxide, talc, aluminum hydroxide, magnesium hydroxide, clay, silica, white carbon and the like are required as fillers in order to improve shapeability. They may be used as appropriate. Among the fillers,
In terms of economy, calcium carbonate is preferred.

The average particle size of the filler is preferably 0.03 to 5 μm from the viewpoint that the effect of imparting shapeability is large. 0.03μ
If it is less than m, the dispersion of the filler may be poor, and
If it exceeds μm, the moldability may be deteriorated.

The amount of the filler used is 10
3 to 150 parts by weight, preferably 5 to 1 part by weight, based on 0 parts by weight.
00 parts by weight is more preferred. If it is less than 3 parts by weight, there is a possibility that there is no effect of imparting excipients, and if it exceeds 150 parts by weight, moldability may be deteriorated or mechanical properties may be deteriorated.

In the present invention, examples of the heat stabilizer include lead heat stabilizers such as tribasic lead sulfate, tin heat stabilizers such as dibutyltin malate, zinc stearate, calcium stearate, and barium stearate. Metal soap, barium-zinc, calcium-zinc, hydrotalcite and the like can be mentioned, and an appropriate amount can be used as needed.

The amount of the heat stabilizer used is as follows.
0.1 to 5 parts by weight, preferably 2 to 2 parts by weight,
4 parts by weight is more preferred. If the amount is less than 0.1 part by weight, the thermal stability may be inferior, and if it exceeds 5 parts by weight, it may be economically undesirable.

Further, in the present invention, those usually used for vinyl chloride resins may be used as processing aids and lubricants.

Further, in the present invention, as the pigment, an appropriate amount of color carbon black, chrome yellow, titanium oxide, phthalocyanine blue or the like may be used as necessary. The thermoplastic elastomer resin composition of the present invention may contain, for modification, if necessary, a plastic such as polyurethane, acrylic resin, ABS resin, MBS resin, nylon, polychloroprene, polyester resin and chlorinated polyethylene. Rubber or the like may be added.

In order to obtain the thermoplastic elastomer resin composition of the present invention, the same blending and pelletizing methods as used for producing ordinary soft vinyl chloride resins can be used. That is, at the time of blending, a conventionally known blender such as a Henschel mixer, a super mixer, and a ribbon blender is used, and after charging each component, a plasticizer is collectively, intermittently or continuously charged and dried up to 80 to 130 ° C. Then, a powder compound of the soft vinyl chloride resin composition is produced. At this time, the order of adding the components is not particularly limited.

The powdery compound of the vinyl chloride resin thus prepared is mixed with a pellet compound of a soft vinyl chloride resin using an ordinary single screw extruder, a twin screw extruder, a kneader, a pressure kneader, a Banbury mixer and the like. Get. When a pellet compound is to be obtained using a pressure kneader, a Banbury mixer, or the like, the step of manufacturing the powder compound by dry-up can be omitted, and the components can be collectively charged to obtain the pellet compound. Then, using a variety of single-screw or twin-screw extruders equipped with a die having the shape of the molded product suitable for the purpose, this pellet compound is extruded by low extrusion extrusion molding with excellent slidability. Goods can be obtained.
In the case of extrusion molding, coextrusion with a metal, another soft vinyl chloride resin composition or a hard vinyl chloride resin composition may be performed.

The extruded product obtained by the present invention can be used for various applications and is not limited to the shape of the molded product. For example, it can be used for industrial applications such as gaskets, sheets, hoses, tubes, glass run channels, weather strips, and cushion materials. It can be used in a wide range of applications, such as for automobiles, automobiles, and building materials.
Among these, since they are excellent in slidability, they are suitable for use in window frames such as glass window frames, and more preferably in window frame gaskets such as automobile weather strips.

[0035]

EXAMPLES Examples of the present invention and comparative examples are described in the table.
The invention is not limited by these.

The components shown in the table used were as described below. -Vinyl chloride resin-1: Vinyl chloride resin having an average degree of polymerization of 2500, Ocean PVC, trade name TH-2500-Vinyl chloride resin-2: Vinyl chloride resin having an average degree of polymerization of 1,000, Ocean PVC, trade name TH-1000 -Plasticizer: di-2-ethylhexyl phthalate (DO
P)-Epoxidized soybean oil: Shin Nippon Rika, trade name Sansocizer E2000-Ba-Zn heat stabilizer: Akishima Chemical, trade name LT660-Calcium carbonate: Takehara Chemical, trade name Sunlight 200
0, average particle size: 1.4 μm ・ Partially crosslinked NBR: GOOD YEAR, amount of bound acrylonitrile: 33% by weight, trade name: CHMIGUM P8B
A-Thermal expansion type microcapsule-1: manufactured by EXPANCEL, trade name EXPANCEL (092) DU120-Thermal expansion type microcapsule-2: manufactured by EXPANCEL, trade name EXPANCEL (091) DE80-Decomposition type foaming agent Azodicarbonamide

Each evaluation method described in the table followed the method described below.

The slidability was evaluated using a tribo gear TYPE: HEIDON-14DR manufactured by Shinto Kagaku Co., Ltd. as a test piece cut from an extruded product, and evaluated by a coefficient of static friction and a coefficient of dynamic friction with glass. The size of the test piece was 3
0mm x 30mm x 5mmt, vertical load 100gf,
600 mm / min. The glass was moved for testing.

The expansion ratio is determined by measuring the specific gravity (foam specific gravity) of a product molded by the underwater substitution method of JIS K7112, and dividing the specific gravity of a non-foam molded product not using a decomposition type foaming agent by the foam specific gravity. did.

The extrusion molding for obtaining a molded product used had an extrusion diameter of 40 mm and (length of the screw of the extruder) / (diameter of the screw of the extruder) (L / D) = 25. The evaluation of the moldability was evaluated as x when the foaming excessively progressed during molding and the molded body surface partially foamed and the molded body could not be obtained, and from the start of molding until a molded article with a stable expansion ratio was obtained.か か る indicates that a time-consuming process was performed, and ◎ indicates that a molded product having a stable expansion ratio was obtained immediately after the start of molding.
And

The evaluation of the soft feeling was performed as follows. Press the molded product and divide the degree of return into three stages by tactile sensation.
And those with a return were marked with ◎.

The magnitude of the set was evaluated by the compression set of the molded article. Specifically, the procedure was performed as follows. After the molded product molded to a thickness of 10 mm is compressed by 25% to a thickness of 7.5 mm, the molded product is left at 70 ° C. × 22 hr and released, and the initial thickness and
It was calculated from the thickness after release as follows. (Compression set) (%) = ｛[initial thickness (mm)] −
[Thickness after release (mm)]｝ / ｛[Initial thickness (mm)]
-7.5 (mm)｝ × 100

Example 1 Each component having the composition shown in Table 1 was dry-blended with a Henschel mixer, pelletized, and molded with a 40 mm extruder. The foaming ratio, moldability, slidability and softness of the molded article of the obtained thermoplastic elastomer composition were evaluated, and the results are shown in Table 1.

[0044]

[Table 1]

Example 2 The procedure of Example 1 was repeated, except that a thermoplastic elastomer composition was obtained using the composition shown in Table 2, and the results are shown in Table 2.

[0046]

[Table 2]

Example 3 The procedure of Example 1 was repeated, except that a thermoplastic elastomer composition was obtained using the composition shown in Table 3, and the results are shown in Table 3.

[0048]

[Table 3]

Example 4 The procedure of Example 1 was repeated, except that a thermoplastic elastomer composition was obtained using the composition shown in Table 4, and the results are shown in Table 4.

[0050]

[Table 4]

Example 5 Experiment no. 2-3 and Experiment Nos. A gasket for a window frame was manufactured using the thermoplastic elastomer composition of 3-8, and the degree of opening and closing of the window glass was evaluated. Experiment No. In the case where the thermoplastic elastomer composition of 2-3 was used, the opening and closing of the window glass could be performed smoothly and was good.
o. When the thermoplastic elastomer composition of 3-8 was used, the opening and closing of the window glass was not smooth and the condition was not good.

[0052]

The use of the heat-expandable microcapsules solves the problem of imparting slidability to a molded article, which could not be achieved by a soft vinyl chloride resin composition using a conventional decomposable foaming agent. Settled. The foamed extruded product of the obtained thermoplastic elastomer composition can be used for a gasket for a window frame because it has reduced weight, soft feeling, and slidability.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI // B29K 227: 06

Claims (5)

[Claims] 1. A thermoplastic elastomer resin composition comprising a vinyl chloride resin, a plasticizer and heat-expandable microcapsules. 2. A thermoplastic elastomer resin composition comprising a vinyl chloride resin, a plasticizer, acrylonitrile-butadiene rubber, and heat-expandable microcapsules. 3. An extruded product obtained by extruding the thermoplastic elastomer composition according to claim 1 or 2. 4. The extruded product according to claim 3, wherein the extruded product is a window frame gasket. 5. A window frame having a window frame gasket obtained by extruding the thermoplastic elastomer composition according to claim 1 or 2.