JPH11151743A - Coextrusion molded product of soft/rigid vinyl chloride resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance heat resistance, secondary processability and sealability by specifying the Vicat softening temp. and impact strength of a rigid vinyl chloride resin compsn. as well as the polymn. degree of the vinyl chloride resin of the compsn. and the content of the heat-resistance enhancing resin thereof and specifying the polymn. degree and hardness of a soft vinyl chloride resin separately extruded to be integrated with the rigid vinyl chloride resin compsn. SOLUTION: A heat resistance enhancing resin is added to 100 pts.wt. vinyl chloride resin with an average polymn. degree of 500-1,300 in a rigid vinyl chloride resin compsn. in an amt. of 10-50 pts.wt. and a chlorinated vinyl chloride resin, an ABS resin or the like are designated. The Vicat softening temp. of a molded product 1 of the rigid vinyl chloride resin is 95 deg.C or higher and the Charpy impact strength thereof is 15 kgf/cm<2> or more. The rigidity A prescribed by JIS K-6301 of a molded product comprising a soft vinyl chloride resin compsn. 2 is 60-90 and the average polymn. degree of the vinyl chloride resin used in the compsn. 2 is 2,000-4,000 and a plasticizer is added to the compsn. The rigid and soft vinyl chloride resin compsns. 1, 2 are extruded from individual extruders and both resins are allowed to meet with each other by one mold to be integrated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a co-extruded product of a soft / hard vinyl chloride resin composition having good appearance and excellent heat resistance, weather resistance, secondary workability, and sealability.

[0002]

2. Description of the Related Art Vinyl chloride resins are widely used in various applications such as building materials, electric components, automobile members, etc. due to their excellent mechanical properties and cost balance. However, ordinary rigid vinyl chloride resin molded products have a low heat distortion temperature, and when exposed to direct sunlight, such as outdoors, the temperature of the molded product rises above its heat distortion temperature and warps or bends the molded product. Deformation occurs, significantly impairing its appearance.

In order to solve such a problem, various methods have been conventionally proposed. For example, a method of coating and extruding a hard vinyl chloride resin on a metal plate such as iron or aluminum or a metal pipe, or adding a heat resistant resin to the hard vinyl chloride resin,
There is a method of improving the heat-resistant temperature of the hard vinyl chloride resin. The former has problems such as waste treatment and problems in secondary workability such as cutting and cutting, and has the disadvantage that the molding equipment becomes large, and the latter method has the disadvantage that mechanical properties and weather resistance are reduced. There is.

Further, co-extruded products of a hard vinyl chloride resin and a soft vinyl chloride resin are also commercially available, but the soft vinyl chloride resin has an average polymerization degree of 1,000 to 1,300 and a medium polymerization degree vinyl chloride resin. It is used and has low rubber elasticity, which causes problems in secondary workability, sealability, appearance of the obtained molded product, and the like.

[0005]

DISCLOSURE OF THE INVENTION The inventor of the present invention is regarded as a disadvantage of plastics and has excellent properties such as heat resistance, weather resistance, secondary workability, sealability and the like required for building materials, electrical installation members, automobile members and the like. As a result of various studies on a vinyl chloride resin molded article, the following invention was reached.

[0006]

(A) Average degree of polymerization: 500 to
A composition containing 30 to 100 parts by weight of a heat resistance improving resin with respect to 100 parts by weight of 1,300 vinyl chloride resins, and a Vicat softening temperature of a molded product of the composition is 95 ° C. or more; A rigid vinyl chloride resin composition having a hardness of 15 kgf / cm ² or more, and (b) a hardness of 60 to 90 specified in JIS K-6301, which is mainly composed of a vinyl chloride resin having an average degree of polymerization of 2,000 to 4,000. A soft / hard vinyl chloride resin composition co-extruded product, which is extruded from a separate extruder with a soft vinyl chloride resin composition and combined in a single mold to be integrated,
It has been found that a soft / hard vinyl chloride resin composition co-extruded article having good appearance and excellent heat resistance, weather resistance, secondary workability, and sealability can be obtained.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below. The vinyl chloride resin having an average degree of polymerization of 500 to 1,300 used in (a) is a vinyl chloride homopolymer, a vinyl chloride and a monomer copolymerizable therewith, which are obtained by a generally used suspension polymerization method. Examples thereof include copolymers of polymers. Examples of monomers copolymerizable with vinyl chloride include vinyl esters such as vinyl acetate and vinyl propionate; (meth) acrylates such as methyl acrylate, ethyl acrylate, methyl methacrylate, and ethyl methacrylate; Olefin monomers such as ethylene and propylene; acrylonitrile, styrene, vinylidene chloride and the like are exemplified.

Examples of the polymer copolymerizable with vinyl chloride include vinyl acetate-ethylene copolymer, chlorinated polyethylene, acrylic polymer, and polyurethane.
As the vinyl chloride and a copolymer of a monomer or a polymer copolymerizable therewith, those having a vinyl chloride content of 50% by weight or more (preferably 70% by weight or more) are used.

[0009] The vinyl chloride resin used in (a) must have an average degree of polymerization of 500 to 1,300. If it is less than 500, the impact strength is remarkably reduced.
The excellent physical properties aimed at by the present invention cannot be obtained. This is
If it exceeds 1,300, the melt viscosity of the molten resin becomes excessively high in the extrusion processing of a hard vinyl chloride resin composition, and the moldability is reduced. The surface properties of the co-extruded product of the vinyl-based resin composition are remarkably reduced, and the appearance of the co-extruded product is deteriorated.

In the present invention, (a) contains a heat resistance improving resin, and the heat resistance of a co-extruded product obtained by adding the heat resistance improving resin is improved. Preferred as the heat resistance improving resin are a chlorinated vinyl chloride resin obtained by post-chlorination of a vinyl chloride resin; a copolymer of vinyl chloride and maleimide; an ABS resin, an AAS (full name) resin, and an ACS (full name). Enter) resin and the like. In addition, the ABS resin exemplified above, AAS
In the resin and the ACS resin, a resin in which part or all of styrene of the copolymer component is replaced with α-methylstyrene may be used, or a resin obtained by copolymerizing maleimide with the α-methylstyrene may be used.

The heat-resistant resin is added in an amount of 30 to 100 parts by weight, preferably 40 to 90 parts by weight, per 100 parts by weight of the vinyl chloride resin in the hard vinyl chloride resin composition (a). If the amount is less than 30 parts by weight, sufficient heat resistance cannot be obtained.If the amount exceeds 100 parts by weight, the melt viscosity of the molten resin becomes excessively high in extrusion processing and the like, and the moldability decreases, and the torque applied to the extrusion molding machine is reduced. And the surface property of the obtained co-extruded soft / hard vinyl chloride resin composition is remarkably reduced, resulting in poor appearance and a large increase in raw material cost of the molded product.

The properties of the hard vinyl chloride resin (a) in the present invention are determined by the heat resistance of the obtained molded article, that is, JIS K-
It is essential that the Vicat softening temperature based on 7206 A is 95 ° C or higher. If this temperature is lower than 95 ° C, the temperature of the molded product rises due to infrared radiation heat from sunlight or ambient temperature when used outdoors or in a car, and when it is severe, it becomes higher than the softening temperature of the molded product and It causes deformation such as warpage and bending.

The other properties of the hard vinyl chloride resin composition (a) of the present invention are as follows. The molded product obtained has a Charpy impact strength of 15 kgf / c based on JIS K-7111.
m ² or more. The reason why the Charpy impact strength must be 15kgf / cm ² or more is to prevent troubles that are likely to occur during secondary processing such as cutting, cutting and drilling of molded products, etc. This is because it is necessary to maintain the performance as described above. The hard vinyl chloride-based resin composition (a) in the present invention may be, if necessary, a conventionally used impact resistance modifier, a fluidity modifier such as an acrylic resin, MBS resin, chlorinated polyethylene, A vinyl acetate-ethylene copolymer or the like may be arbitrarily selected and added as long as the effects of the present invention are not impaired.

The vinyl chloride resin having an average degree of polymerization of 2,000 to 4,000 used as the main component of (b) in the present invention can be obtained by a commonly used suspension polymerization method as in (a). This is exemplified by a vinyl chloride homopolymer, a copolymer of vinyl chloride and a monomer or polymer copolymerizable therewith, and a post-chlorinated vinyl chloride polymer. Examples of the monomer or polymer which can be copolymerized with vinyl chloride are the same as those in (a), and the content of vinyl chloride contained in this copolymer is also the same as in (a).

It is essential that the vinyl chloride resin used as the main component of (b) has an average degree of polymerization of 2,000 to 4,000. If it is less than 2,000, the appearance of the molded product obtained by co-extrusion, that is, the surface of the molded product is uneven and poor, and the rubber elasticity is low and the sealing property is poor, which is not preferable. On the other hand, if it exceeds 4,000, molding processability is undesirably reduced. By setting the average degree of polymerization within the range of 2,000 to 4,000, the co-extrusion metal which is integrated with the melt of the hard vinyl chloride resin composition extruded from the other extruder during co-extrusion molding. Even in a mold, a remarkable decrease in melt viscosity does not occur, and a uniform co-extruded product can be obtained which is balanced with the melt viscosity of the melt of the hard vinyl chloride resin composition.

In the soft vinyl chloride resin composition (b) of the present invention, it is essential that the hardness of the molded product specified in JIS K-6301 be in the range of 60 to 90. If the hardness is less than 60, the soft portion of the co-extruded product becomes too soft, and the sealability (packing effect) of the co-extruded product intended for the present invention cannot be obtained.
In addition, the melt viscosity of the melt of the soft vinyl chloride resin composition becomes too low in view of the set temperature of the co-extrusion die, and it is difficult to obtain a balance with the melt viscosity of the hard vinyl chloride resin composition. Impairs appearance. On the other hand, if the hardness exceeds 90, the soft portion of the co-extruded product becomes hard, which causes inconveniences such as a decrease in the sealing property (packing effect) of the co-extruded product which is the object of the present invention.

In the soft vinyl chloride resin composition of (b), the hardness A of the molded article specified in JIS K-6301 is 60
As a method for adjusting the content to within the range of ~ 90, phthalic acid esters, trimellitic acid esters, and aliphatic 2
Basic ester; phosphate ester; epoxy plasticizer; polyester plasticizer; vinyl acetate-ethylene copolymer;
A method is used in which one or more polymer plasticizers such as NBR and polyurethane are added. These plasticizers are usually added in an amount of 50 to 150 parts by weight based on 100 parts by weight of the vinyl chloride resin.

In order to carry out the present invention, two or more single-screw extruders or two or more twin-screw extruders are used, and a hard and soft vinyl chloride resin composition is extruded from each individual extruder, and one mold is used. Inside, the two resin compositions are merged, and the integrated melt is shaped, cooled, taken off, and cut to obtain a co-extruded product. At this time, the hard and soft molding materials may be in the form of powder or pellets.

In the above-mentioned hard and soft vinyl chloride resin compositions, various additives usually used, for example, heat stabilizers, fillers, lubricants, foaming agents, pigments and ultraviolet absorbers can be appropriately used. . As a heat stabilizer, a tin-based stabilizer such as dibutyltin mercapto, a lead-based stabilizer such as tribasic lead sulfate,
Metal soaps such as calcium stearate and barium, and composites thereof. Calcium carbonate as filler,
Clay, talc, etc. can be used in an appropriate amount. Examples of the lubricant include various metal soaps, fatty acids, polyethylene wax, etc., and as necessary, a foaming agent such as azodicarboxylic acid amide, an ultraviolet absorber for improving weather resistance, and an oxidizing agent. The use of inorganic or organic pigments, such as titanium or phthalocyanine blue, can be used at all.

Specific examples of the co-extrusion molded article of the present invention include window frames, screen doors, deck materials, clapboards, decorative boards, and the like in the case of building materials. Hard parts having excellent heat resistance and impact resistance are used as building materials. While exhibiting the function, the soft part with excellent rubber elasticity improves the sealability with other members and can greatly improve the workability, and furthermore, the soft part is considered as a defect of the hard vinyl chloride resin. Weather resistance can be improved by suppressing the occurrence of a choking phenomenon or the like and preventing discoloration. FIGS. 1, 4 to 6 show examples of the cross-sectional shape of the co-extruded product of the present invention, which is orthogonal to the extrusion direction at the time of molding. In addition, the same effects as described above can be expected for hard-soft coextrusion two-layer pipes and various indoor / outdoor wiring materials for electrical installation members. As for automobile parts, since automobiles are used outdoors and exposed to high temperatures, this molded product is particularly useful, and has features such as being able to sufficiently exhibit the drainage effect as a member for window frames, step materials, and loading platforms of automobiles. Have.

[0021]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. The hard vinyl chloride resin composition and the soft vinyl chloride resin composition used in the present invention were produced by the following methods. (1) Production Example of Hard Vinyl Chloride Resin Composition The following raw materials were charged into a 100-liter Henschel mixer manufactured by Mitsui Mining Co., Ltd. at the mixing ratio (parts by weight) shown in Table 1, and the mixture was stirred and heated to 120 ° C. After warming, cool to 50 ° C,
A powdery hard vinyl chloride resin molding material was obtained. The above powdery molding material was L / D = 2 with a 50 mmφ single screw extruder.
2. Pellets (R-1) to (R-10) were obtained using a full flight screw having a compression ratio of 2.0 under the following temperature conditions. Screw rotation _{40rpm, C 1 = 135 ℃,} C 2 = 145 ℃,
C ₃ = 165 ° C., AD = 160 ° C., D = 165 ° C. TK-400: Shin-Etsu Chemical Co., Ltd. vinyl chloride homopolymer P = 400 (P is the average degree of polymerization, the same applies hereinafter), TK-800: Shin-Etsu Chemical Industrial Co., Ltd. vinyl chloride homopolymer P = 800, TK-1000: Shin-Etsu Chemical Co., Ltd. vinyl chloride homopolymer P = 1,050, TK-1700: Shin-Etsu Chemical Co., Ltd. vinyl chloride homopolymer P = 1,700 HA-31K: Post-chlorinated vinyl chloride manufactured by Sekisui Chemical Co., Ltd. MK-20: Heat-resistant ABS resin manufactured by Nippon Synthetic Rubber Co., Ltd. V-6815: Heat-resistant AAS resin manufactured by Hitachi Chemical Co., Ltd., C- 223: MBS resin manufactured by Mitsubishi Rayon Co., Ltd.

(2) Production Example of Soft Vinyl Chloride Resin Composition The following raw materials are charged into a 100-liter Henschel mixer manufactured by Mitsui Mining Co., Ltd. at the blending ratio (parts by weight) shown in Table 2 and heated to 110 ° C. After stirring and raising the temperature, the mixture was cooled to 40 ° C. to obtain a powdery soft vinyl chloride resin molding material. L / D = 22, 50 / φ single screw extruder
Pellets (S-1) to (S-5) were obtained under the following temperature conditions using a full flight screw having a compression ratio of 3.0. Screen 80 ^# x 1, 100 ^# x 1, screw rotation 4
_{0rpm C 1 = 120 ℃, C} 2 = 135 ℃, C 3 = 150 ℃, AD = 1
45 ° C, D = 145 ° C TK-1300: Vinyl chloride homopolymer P = 1,300, manufactured by Shin-Etsu Chemical Co., Ltd. TK-2500HS: Vinyl chloride homopolymer P = 2,450, methablene P-551, manufactured by Shin-Etsu Chemical Co., Ltd. PMMA manufactured by Mitsubishi Rayon Co., Ltd.
Elastane 301A: Chlorinated polyethylene manufactured by Showa Denko KK, Ba-Zn based powder: RUP-14, Ba-Zn based liquid manufactured by Asahi Denka Kogyo Co., Ltd. AC manufactured by Asahi Denka Kogyo Co., Ltd. -186, epoxy oil: O-130P manufactured by Asahi Denka Kogyo Co., Ltd.

(1) The obtained rigid vinyl chloride resin composition pellets were kneaded with a 6-inch roll at a temperature of 160 ° C. for 5 minutes to prepare a roll sheet having a thickness of 0.8 mm. Using the obtained roll sheet, the Vicat softening temperature (° C.) and the Charpy value (unit: kgf / cm ² ) were measured by the methods described below, and the results are shown in Table 1. Measurement method of Vicat softening temperature: Measured according to JIS K-7206A. Measurement method of Charpy value: Measured according to JIS K-7111.

[0024]

[Table 1]

The soft vinyl chloride resin composition pellets obtained in (2) were kneaded with a 6-inch roll at a temperature of 150 ° C. for 5 minutes to prepare a roll sheet having a thickness of 0.8 mm. The hardness A was measured by the method of JIS K-6301 using the obtained roll sheet, and the result is shown in Table 2.

[0026]

[Table 2]

(3) Co-extruded products (A-1) to (A-6) and (B
-1) Production of (B-8) The hard and soft pellet-like materials obtained in (1) and (2) above were combined with the hard and soft parts shown in Tables 3 and 4 to obtain a 50 mmφ single axis. The extruder (full flight screw with a compression ratio of 2.0 for hard extrusion) and a 30 mmφ single screw vertical extruder (a full flight screw with a compression ratio of 3.5 for soft extrusion) and double extrusion using a crosshead die are shown in FIG. 1 below. A molded article having a cross-sectional shape was obtained. The molding temperature conditions for each extruder are as follows. 50mmφ single screw extruder (for _{hard) C 1 = 145 ℃, C} 2 = 165 ℃, C 3 = 185 ℃, AD = 1
80 ℃, D = 190 ℃ 30mmφ Tanjikutate extruder (for _{soft) C 1 = 140 ℃, C} 2 = 165 ℃, adapter 160 ° C., the nozzle portion 170 ℃, D = 190 ℃

The obtained co-extruded products (A-1) to (A-6) and
For (B-1) to (B-8), moldability, heat resistance,
The appearance of the molded article, weather resistance, secondary workability (punching workability), and sealability were evaluated, and the results are shown in Tables 3 and 4. (Evaluation criteria for moldability)）: Good ○: Slightly good ×: Difficult to mold (Evaluation criteria for heat resistance) The shape after standing in an oven at 85 ° C. for 30 minutes was visually observed ◎: No deformation of the shape ○: There is some deformation of the shape. △: Warpage occurs. ×: Warpage occurs and the whole is deformed. (Evaluation criteria for secondary workability) FIG. 1 of the obtained co-extruded product
A hole having a diameter of 3 mm was punched out from the portion A of the above, and the state of the hole was visually observed. ：: no cracking △: cracking ×: cracking (evaluation criteria for molded article appearance) 品: good shape and gloss △: good shape but slightly poor gloss ×: poor shape and gloss (weather resistance) Evaluation criteria for sunshine)
Visually observe the discolored state of the surface of the soft part of the molded article after exposure for 500 hours. ：: Almost no discoloration ×: Discolored A glass plate of 66 mm × 66 mm × 5 mm was fitted as described above to produce a frame plate as shown in FIG. 3, and the frame plate was set upright to discharge water toward the front center for 10 minutes. After the water was released, the bleeding state of the portion B in FIG. 2 was visually observed. ：: Almost no water bleeding ×: Water bleeding

[0029]

[Table 3]

[0030]

[Table 4]

[0031]

According to the present invention, a co-extruded product of a soft / hard vinyl chloride resin composition having a good appearance and excellent heat resistance, weather resistance, secondary workability and sealability can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view orthogonal to the extrusion direction of an example of a co-extruded product of the present invention.

FIG. 2 is a similar sectional view of a frame plate in which a glass plate is fitted into the co-extruded product shown in the preceding figure.

FIG. 3 is a front view of the frame plate of the preceding figure.

FIG. 4 is a cross-sectional view of one example of a co-extruded molded product of the present invention, which is orthogonal to the extrusion direction of the molded product.

FIG. 5 is a cross-sectional view of one example of a co-extruded molded product of the present invention, which is orthogonal to the extrusion direction of the molded product.

FIG. 6 is a cross-sectional view of one example of a co-extruded molded product of the present invention, which is orthogonal to the extrusion direction of the molded product.

[Explanation of symbols]

 1 soft part, 2 hard part, 3 glass plate.

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁶ Identification code FI B29L 31:10 31:30 31:34

Claims (4)

[Claims] (A) 100 parts by weight of a vinyl chloride resin having an average degree of polymerization of 500 to 1,300, and 30 to 100 parts by weight of a resin having improved heat resistance.
A hard vinyl chloride-based resin composition having a Vicat softening temperature of 95 ° C. or more; and a Charpy value of 15 kgf / cm ² or more, comprising: ) A soft vinyl chloride resin composition having a hardness of 60 to 90 as defined in JIS K-6301 and containing a vinyl chloride resin having an average degree of polymerization of 2,000 to 4,000 as a main component is extruded from a separate extruder into one mold. A soft / hard vinyl chloride-based resin composition co-extruded product characterized by being merged and integrated in the interior. 2. The method according to claim 1, wherein the material is for building materials.
A co-extruded product of the soft / hard vinyl chloride resin composition described in the above. 3. The co-extruded product of the soft / hard vinyl chloride resin composition according to claim 1, which is for electrical installation members. 4. The co-extruded product of the soft / hard vinyl chloride resin composition according to claim 1, which is used for automobile parts.