JPH09208778A - Impact-resistant rigid vinyl chloride resin pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the above product comprising a vinyl chloride resin, specific stabilizers, and an impact resistance-improving agent, capable of being produced with a simple installation without lowering the ability of the installation and without deteriorating the long running property of the installation, and excellent in appearance. SOLUTION: This vinyl chloride resin pipe comprises (A) 100 pts.wt. of a vinyl chloride resin, (B) 0.1-2 pts.wt. of a calcium fatty acid salt as a stabilizer, (C) 0.2-2 pts.wt. of a zinc fatty acid salt as a stabilizer, and (D) 3-12 pts.wt. of an impact resistance-improving agent. The components B and C are preferably stearic acid salts from points where the components are non-toxic, do not cause sulfuration pollution, are excellent in lubricity and gelation, etc. The component D is preferably a butadiene-methacrylate ester-styrene copolymer from the points of a stirring property and physical properties. The objective product is preferably obtained by stirring and mixing the components A-D with a conventional means such as a blender within 5 minutes without heating the components and subsequently molding the mixture by a conventional extrusion molding method.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an impact-resistant hard vinyl chloride pipe mainly used for waterworks.

[0002]

2. Description of the Related Art Conventionally, impact resistant hard vinyl chloride pipes for waterworks have been treated with tin sulfide as a non-toxic stabilizer,
Many of them are mainly composed of mercaptide or mercapto acid ester salt. While these tin-based stabilizers have excellent thermal stability and little coloring during molding, many of them are liquids, so they are agitated and mixed with vinyl chloride resin and other additives. Therefore, it took a long time to uniformly disperse the particles, and sometimes stirring under heating was unavoidable. For this reason, compared with the powder / granular stabilizer, the equipment capacity is limited, and there is a drawback that equipment investment such as a cooling mixer and installation space are required. In addition, with these tin-based stabilizers, plate-out (a film formed by the gradual deposition of the compounding components on the inner surface of the mold) is generated during molding, and mesiness (the compounding components are gradually added to the periphery of the die outlet). It has a drawback that the long-run property is poor and the appearance (gloss, streak) of the pipe is inferior because the growth of the deposited material) is fast and cleaning of these is required.

[0003]

SUMMARY OF THE INVENTION Therefore, the object of the present invention is to provide a shock-resistant product having an excellent appearance, which can be manufactured without requiring a new capital investment, without lowering the facility capacity, and without impairing the long-run property. To provide a rigid vinyl chloride pipe.

[0004]

The impact-resistant hard vinyl chloride pipe according to the present invention comprises a calcium fatty acid salt as a stabilizer of 0.1 to 100 parts by weight of vinyl chloride resin.
2 parts by weight, 0.2 to 2 parts by weight of a fatty acid salt of zinc, and 3 to 12 parts by weight of an impact modifier are featured.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The vinyl chloride resin used in the impact-resistant hard vinyl chloride pipe of the present invention includes vinyl chloride homopolymer and vinyl chloride monomer in an amount of 50% by weight or more. Containing copolymers with vinyl monomers copolymerizable therewith, vinyl chloride monomers and various polymers or graft copolymers with polyvinyl chloride and vinyl monomers, post-chlorination chlorination Vinyl polymers and mixtures thereof are included, and those produced by any method such as bulk polymerization, suspension polymerization, emulsion polymerization and solution polymerization are also included.

Vinyl-based monomers used in this copolymerization or graft copolymerization include olefins such as ethylene and propylene; halogenated olefins other than vinyl chloride such as vinylidene chloride and vinyl fluoride; vinyl acetate and laurin. Vinyl esters such as vinyl acetate; alkyl vinyl ethers such as 2-ethylhexyl vinyl ether and dodecyl vinyl ether; acrylic acid or its esters such as acrylic acid, methyl acrylate, ethyl acrylate; methacrylic acid, methyl methacrylate,
Methacrylic acid or its esters such as 2-ethylhexyl methacrylate; maleic acid or its esters, maleic anhydride, acrylonitrile, acrylic derivatives such as styrene; Nt-butylmaleimide, N-
Examples thereof include N-substituted maleimides such as cyclohexylmaleimide, which may be used alone or in combination of two or more. Examples of the polymer that can be graft-copolymerized with a vinyl chloride monomer include ethylene-vinyl acetate copolymer, ethylene-acrylic acid ester copolymer, chlorinated polyethylene, polyurethane, butadiene-methacrylic acid ester-styrene copolymer. Polymer, butadiene-acrylonitrile-styrene copolymer, polybutyl acrylate,
Examples thereof include butyl rubber polystyrene, styrene-butadiene copolymer, crosslinked acrylic rubber and the like.

Fatty acid salts of calcium and zinc used as stabilizers include, for example, laurate, stearate, palmitate, oleate, ricinoleate, etc. In terms of excellent lubricity, good gelling property, and synergistic effect,
Preference is given to using stearates. Calcium fatty acid salt and zinc fatty acid salt are
It is used in combination in the range of 0.1 to 2 parts by weight and 0.2 to 2 parts by weight with respect to 0 parts by weight, respectively. If the fatty acid salt of calcium is less than 0.1 parts by weight, the thermal stability will be insufficient, and if it exceeds 2 parts by weight, the moldability will decrease and coloring during molding will increase, such being undesirable. If the fatty acid salt of zinc is less than 0.2 parts by weight, the thermal stability will be insufficient, and if it exceeds 2 parts by weight, rapid deterioration tends to occur during molding, which is not preferable.

As impact resistance modifiers, butadiene-methacrylic acid ester-styrene copolymer, butadiene-
Acrylonitrile-styrene copolymers, polyacrylic acid esters and copolymers thereof with crosslinkable vinyl monomers, chlorinated polyethylene and the like can be mentioned, but in terms of stirring properties and physical properties, butadiene-methacrylic acid ester-styrene copolymer Use is preferred. These impact modifiers are used in the range of 3 to 12 parts by weight based on 100 parts by weight of the vinyl chloride resin. If it is less than 3 parts by weight, the impact resistance of the pipe will be lowered, and if it exceeds 12 parts by weight, the formability and the tensile strength of the pipe will be lowered, which is not preferable. In addition to the above, the impact resistant hard vinyl chloride pipe of the present invention may be added to a usual vinyl chloride resin, if necessary, for example, a lubricant, an antistatic agent, a processing aid, an antioxidant, an ultraviolet ray. Absorbents, colorants, fillers and the like are used as appropriate.

The above-mentioned components may be stirred and mixed within 5 minutes without heating using conventional means such as a super mixer and a blender, and the compound thus obtained does not require a cooling mixer. The impact resistant hard vinyl chloride pipe of the present invention can be obtained by the conventional extrusion molding method.

[0010]

EXAMPLES The present invention will be described more specifically below with reference to Examples and Comparative Examples. Examples 1 to 4 and Comparative Examples 1 to 8 Components of the types and amounts shown in Table 1 were added to a super mixer, and the mixture was stirred and mixed under the conditions shown in Table 1, and the obtained blends were heated and kneaded with an extruder. This was extruded into a pipe shape from a mold with a diameter of 20 mm (HIVP20) and cooled and solidified in a water tank to produce a hard vinyl chloride pipe with impact resistance. The details of the raw materials used are shown below. The following tests were conducted on the obtained impact resistant hard vinyl chloride pipe, and the results are shown in Table 1 together with the stirring and mixing conditions.

(Details of raw materials used) -Vinyl chloride resin: TK-1000 (manufactured by Shin-Etsu Chemical Co., Ltd.)-Calcium stearate: SC-100 (manufactured by Sakai Chemical Co., Ltd.)-Zinc stearate: SZ -2000 (Same as above) -Tin mercapto-based stabilizer: ADVASTAB TM-188J (Katsuda Kako Co., Ltd., trade name) -Lubricant: Solister SL-02 (RIKEN Vitamin Co., Ltd. trade name) -Processing aid: Metablen P- 551A (manufactured by Mitsubishi Rayon Co.,
Product name) ・ Impact resistance modifier: BTA-751 (Kanefuchi Chemical Co., Ltd. product name) The lubricant, processing aid and colorant in Table 1 are 30
The component ratio is ˜60 wt%, 20-40 wt%, 10-30 wt%.

(Test method and its specification) 1) Moldability XX: Unmoldable, X: Moldable but load too high or conversely too low, large load variation, Δ: slightly high load, ◯: Good, evaluated in 4 stages. 2) Plate-out and generation of eyelids In Example 1 and Comparative Example 8, continuous hard vinyl chloride pipes were used.
It was manufactured for 12 hours, and the situation of occurrence of bouts just before the end and the state of plate out on the inner surface were investigated by dismantling the die after the end. 3) Smoothness and gloss x: Inferior, Δ: Slightly inferior, ◯: Fair, ⊚: Excellent. 4) Streaks In 2) above, the appearance of the pipe was confirmed just before the end. 5) Tensile test Tensile yield strength (N / m ² ) and tensile elongation (%) were measured according to JIS K 6742 (rigid vinyl chloride pipe for water supply). 6) 50% failure height test The 50% failure height (cm) was measured according to JIS K 7211 (General rule for the method of falling weight impact test of hard plastic). A test pipe having a length of 15 cm was cooled at −10 ° C. for 2 hours, and then repeated with 20 tests using a 7.7 kg weight (cylindrical, diameter 50 mm).

[0013]

[Table 1]

Under the conditions of the present invention of Examples 1 to 4, the appearance and test results of the pipes were good, even though the stirring time was short and the stirring temperature was near room temperature. -In Comparative Examples 1 to 4, the appearance and moldability of the pipes were deteriorated. -Comparative example 3 could not be molded, and comparative example 4 showed a decrease in performance.・ In Comparative Example 5, the fracture height is reduced by 50% (impact resistance is reduced).
Was seen. -In Comparative Example 6, a decrease in formability and tensile yield strength (tensile strength) was observed. -In Comparative Example 7, when a tin mercapto-based stabilizer is used, it is understood that an impact resistant hard vinyl chloride pipe having sufficient performance cannot be obtained under the same stirring conditions as in Examples 1 to 4. In Comparative Example 8, such a long-time heating and stirring gives a shock-resistant hard vinyl chloride pipe having sufficient performance even with a tin mercapto-based stabilizer, but if the stirring time and the cooling time are combined, 5 times as long as in Examples 1 to 4,
In addition, the ability to make formulations is severely limited as it must be heated to 120 ° C. In addition, the appearance of the pipe was deteriorated in gloss and streaks were observed, and plate-out and eye damage were observed during molding.

[0015]

EFFECTS OF THE INVENTION According to the present invention, since fatty acid salts of calcium and zinc are used as a non-toxic stabilizer for powders and granules, impact resistance can be reduced with simpler equipment without lowering the equipment capacity. It is possible to manufacture a rigid vinyl chloride pipe. Further, since there is little occurrence of plate-out and dents, a product with excellent long-run property and good appearance can be obtained.

Claims (1)

[Claims] 1. A calcium fatty acid salt of 0.1 to 2 parts by weight, a zinc fatty acid salt of 0.2 to 2 parts by weight, and an impact resistance modifier of 3 to 12 per 100 parts by weight of a vinyl chloride resin.
Impact resistant hard vinyl chloride pipe characterized by comprising parts by weight.