JPH10306194A - Rigid vinyl chloride resin pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin pipe which is excellent not only in mechanical strengths and resistances to impact and heat but also in external appearance and running properties by melt extruding a compsn. which comprises a vinyl chloride resin obtd. by grafting vinyl chloride onto a specific acrylic copolymer, a heat stabilizer. stearic acid, calcium stearate, and process aids. SOLUTION: This pipe is produced by melt exruding a compsn. which comprises 100 pts.wt. vinyl chloride resin, 0.2-7 pts.wt. heat stabilizer, 0.1-5 pts.wt. stearic acid, 0.1-5 pts.wt. calcium stearate, 0.1-10 pts.wt. process aid having a wt. average mol.wt. of 60,000 or higher, and 0.1-1 pt.wt. process aid having a wt. average mol.wt. lower than 60,000. The vinyl chloride resin has a degree of polymn. of 800-2,000 and is prepd. by grafting, by suspension polymn., 97-90 wt.% vinyl chloride onto 3-10 wt.% acrylic polymer which is obtd. by copolymerizing 100 pts.wt. monomer mixture comprising 80-100 wt.% alkyl (meth)acrylate which gives a homopolymer having a Tg lower than -20 deg.C and 20-0 wt.% monomer which gives a homopolymer having a Tg of -20 deg.C or higher with 0.1-10 pts.wt. polyfunctional monomer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rigid vinyl chloride resin tube.

[0002]

2. Description of the Related Art A vinyl chloride resin composition has mechanical strength,
Since it is a material excellent in weather resistance, chemical resistance, etc., it is widely used for building members, pipework equipment, housing materials and the like.
However, since the vinyl chloride resin composition has poor impact resistance, various modification methods have been proposed.

[0003] For example, as a method for improving impact resistance, chlorinated polyethylene (CP)
E), a method in which a rubber-based resin such as methyl methacrylate-butadiene-styrene copolymer (MBS), acrylic rubber or the like is compounded as an impact resistance reinforcing agent, and molded.

However, when a vinyl chloride resin composition containing an impact resistance enhancer is melt-extruded into a tubular shape to produce a hard vinyl chloride resin tube, when CPE is added, the low-temperature impact resistance becomes poor, and sufficient There is a problem that the molding temperature width at which a high impact resistance can be obtained becomes very narrow. When MBS is blended, there are problems such as a significant decrease in impact resistance after the exposure test and an increase in load during molding. When the acrylic rubber is compounded, it is difficult to uniformly disperse the particles at the time of molding, and there is a drawback that the impact resistance of the vinyl chloride resin becomes uneven depending on the processing conditions. Further, the impact resistance of a rigid vinyl chloride-based resin tube formed by melt extrusion from a vinyl chloride resin composition containing an impact-resistant reinforcing agent was not sufficient.

Japanese Patent Application Laid-Open No. 62-36412 discloses a vinyl chloride resin composition in which vinyl chloride is graft-polymerized to a specific acrylic copolymer. But,
A rigid vinyl chloride resin tube obtained by using the vinyl chloride resin composition and melt-extruding it into a tubular shape has the disadvantage that although the impact resistance is improved, the mechanical strength and heat resistance are reduced. doing. Further, the obtained hard vinyl chloride resin tube was not sufficiently satisfactory in surface condition (gloss and smoothness) and did not have stable running properties.

[0006]

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks, the present invention is to provide a hard vinyl chloride resin tube excellent in impact resistance, mechanical strength and heat resistance and excellent in appearance and running properties. With the goal.

[0007]

The rigid vinyl chloride resin tube of the present invention has a homopolymer having a glass transition temperature of -20 ° C.
Less than 80-1 alkyl (meth) acrylate monomers
00% by weight and the glass transition temperature of the homopolymer is -20.
Acrylic obtained by copolymerizing 100 parts by weight of an acrylic mixed monomer (a-1) composed of 20 to 0% by weight of a monomer having a temperature of at least 0 ° C. and 0.1 to 10 parts by weight of a polyfunctional monomer (a-2). System copolymer (a) 3 to 10% by weight
The degree of polymerization obtained by graft copolymerizing 97 to 90% by weight of vinyl chloride (b) by suspension polymerization is 800 to
0.2 to 7 parts by weight of heat stabilizer (B), 0.1 to 5 parts by weight of stearic acid (C), and 0.1 to 5 parts by weight of calcium stearate (D) based on 100 parts by weight of 2,000 vinyl chloride resin (A). 1 to 5 parts by weight, and a weight average molecular weight of 6
10,000 or more processing aids (E-1) 0.1 to 10 parts by weight and processing aids (E-2) having a weight average molecular weight of less than 60,000 0.1 to 1
It is characterized in that it is obtained by melt-extruding a vinyl chloride-based resin composition blended in parts by weight into a tube.

In the present invention, among the monomers used for the acrylic mixed monomer (a-1), the alkyl (meth) acrylate monomer having a glass transition temperature of a homopolymer of less than -20 ° C. is not particularly limited. For example, ethyl acrylate, n-propyl acrylate,
Isobutyl acrylate, n-butyl acrylate, s
ec-butyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl (meth) acrylate, isooctyl acrylate, n
-Decyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl acrylate, lauryl (meth) acrylate, 2-acryloyloxyethyl succinic acid, and the like. These may be used alone,
Two or more kinds may be used in combination.

The glass transition temperature of the above homopolymer is -2.
The content of the alkyl (meth) acrylate monomer having a temperature of less than 0 ° C is 80 to 80% in the acrylic mixed monomer (a-1).
100% by weight. When the content is less than 80% by weight, it is difficult to obtain impact resistance, so the content is limited to the above range.

Also, an acrylic mixed monomer (a-1)
The monomers having a glass transition temperature of a homopolymer of −20 ° C. or higher among the monomers used for the above are not particularly limited. For example, methyl (meth) acrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n- Alkyl (meth) such as butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, lauryl acrylate, myristyl (meth) acrylate, palmityl (meth) acrylate, and stearyl (meth) acrylate Acrylates: Polarity such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-acryloyloxyethyl phthalic acid Containing vinyl monomers; styrene,
aromatic vinyl monomers such as α-methylstyrene and vinyltoluene; unsaturated nitriles such as acrylonitrile and methacrylonitrile; vinyl esters such as vinyl acetate and vinyl propionate. These may be used alone or in combination of two or more.

The above homopolymer has a glass transition temperature of -2.
The monomer having a temperature of 0 ° C. or higher can arbitrarily adjust the glass transition temperature of the obtained acrylic copolymer (a). The content of the homopolymer having a glass transition temperature of −20 ° C. or higher is determined by the amount of the acrylic mixed monomer (a-
In 1), the content is 0 to 20% by weight. If it exceeds 20% by weight, sufficient impact resistance cannot be obtained, so that it is limited to the above range.

The polyfunctional monomer (a-2) is not particularly restricted but includes, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate and triethylene glycol di (meth) acrylate.
Di (meth) acrylates such as acrylate, 1,6-hexanediol di (meth) acrylate and trimethylolpropane di (meth) acrylate; trimethylolpropane tri (meth) acrylate, ethylene oxide-modified trimethylolpropane tri (meth) acrylate Tri (meth) acrylates such as pentaerythritol tri (meth) acrylate; pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, diallyl phthalate, diallyl maleate, diallyl fumarate, diallyl succinate, triallyl Diallyl compounds and triallyl compounds such as isocyanurate; divinyl compounds such as divinylbenzene and butadiene; These may be used alone or in combination of two or more.

The acrylic copolymer (a) is obtained by copolymerizing 100 parts by weight of the acrylic mixed monomer (a-1) and 0.1 to 10 parts by weight of the polyfunctional monomer (a-2). can get. When the content of the polyfunctional monomer (a-2) is less than 0.1 part by weight, it is difficult to obtain impact resistance with a decrease in the crosslink density. Since the impact resistance and the tensile strength are hardly obtained by the rise, it is limited to the above range, and preferably 0.1 to 8 parts by weight.

The method for obtaining the acrylic copolymer (a) is not particularly limited, and examples thereof include an emulsion polymerization method and a suspension polymerization method. Considering the impact resistance, the emulsion polymerization method is preferred.

In the emulsion polymerization method, an emulsifying dispersant is added for the purpose of improving the dispersion stability of the above-mentioned acrylic mixed monomer in an emulsion and effecting the polymerization efficiently. The emulsifying and dispersing agent is not particularly limited. For example, anionic surfactants such as polyoxyethylene nonylphenyl ether sulfate (trade name “Hitenol N-08” manufactured by Daiichi Kogyo Seiyaku Co., Ltd.); Nonionic surfactants Agents; partially saponified polyvinyl alcohol; cellulosic dispersants; gelatin and the like.

[0016] In the emulsion polymerization method, a polymerization initiator is used. The polymerization initiator is not particularly limited and includes, for example, water-soluble polymerization initiators such as potassium persulfate, ammonium persulfate, and hydrogen peroxide; benzoyl peroxide;
Organic peroxides such as lauroyl peroxide; azo initiators such as azobisisobutyronitrile; Further, if necessary, a pH adjuster, an antioxidant, and the like may be added.

The emulsion polymerization method is not particularly limited.
From the difference in the method of adding the monomer, for example, a batch polymerization method,
Examples include a monomer dropping method and an emulsion dropping method.
The batch polymerization method is, for example, in a polymerization reactor with a jacket, pure water, an emulsifying dispersant, a polymerization initiator, a mixed monomer comprising the acrylic mixed monomer and the polyfunctional monomer are added all at once, and nitrogen is added. Under a condition of oxygen removal by air flow and pressurization, the emulsion is sufficiently emulsified by stirring, and then the polymerization is carried out by heating the inside of the vessel with a jacket.

In the monomer dropping method, for example, pure water, an emulsifying dispersant, and a polymerization initiator are placed in a polymerization reactor equipped with a jacket, and first, the inside of the reactor is jacketed under a condition of oxygen removal and pressurization under a nitrogen stream. And then gradually polymerize the mixture by dropping the above-mentioned monomer mixture in a fixed amount.

In the emulsion dropping method, for example, an emulsified monomer is prepared in advance by sufficiently emulsifying the above-mentioned mixed monomer, emulsifying dispersant, and pure water with stirring, and then pure water, a polymerization initiator are introduced into a jacketed polymerization reactor. , The vessel is first heated by a jacket under the conditions of oxygen removal and pressurization under a nitrogen stream, and then the emulsified monomer is dropped by a predetermined amount to carry out polymerization.

The vinyl chloride resin (A) is obtained by graft copolymerizing 97 to 90% by weight of vinyl chloride (b) with 3 to 10% by weight of the acrylic copolymer (a) by suspension polymerization. can get. The content of the acrylic copolymer (a) depends on the vinyl chloride resin (A) obtained.
And 3 to 30% by weight. If it is less than 3% by weight, it is difficult to obtain sufficient impact resistance, and if it is more than 30% by weight, the mechanical strength such as bending strength and tensile strength becomes low. Is 3-20% by weight
It is.

The content of the vinyl chloride (b) is as follows:
90 to 97% by weight in the obtained vinyl chloride resin (A)
It is. If it is less than 90% by weight, mechanical strength such as bending strength and tensile strength will be low, and if it exceeds 97% by weight, it will be difficult to obtain sufficient impact resistance, so it will be limited to the above range. Preferably, it is 92 to 97% by weight.

The average degree of polymerization of the vinyl chloride copolymer is from 800 to 2,000. If it is less than 800, it becomes difficult to obtain impact resistance. Conversely, if it exceeds 2,000, the load at the time of extrusion becomes high and extrusion becomes difficult.
It is limited to the above range, preferably, 1000 to 1600
It is.

The method for obtaining the vinyl chloride resin (A) is not particularly limited, and examples thereof include an emulsion polymerization method and a suspension polymerization method. Among them, the suspension polymerization method is preferred. In the suspension polymerization method, a dispersant and an oil-soluble polymerization initiator are used for the purpose of improving the dispersion stability of the acrylic copolymer (a) and efficiently performing the graft copolymerization of vinyl chloride. Good.

The dispersant is not particularly restricted but includes, for example, methylcellulose, ethylcellulose, hydroxypropylmethylcellulose, polyvinyl alcohol, partially saponified polyvinyl acetate, gelatin, polyvinylpyrrolidone, starch, maleic anhydride-styrene copolymer and the like. Is mentioned. These may be used alone,
Two or more kinds may be used in combination.

As the above-mentioned oil-soluble polymerization initiator, a radical polymerization initiator is suitably used from the viewpoint of being advantageous for graft copolymerization. The radical polymerization initiator is not particularly restricted but includes, for example, lauroyl peroxide, t-butyl peroxypivalate, diisopropyl peroxydicarbonate, dioctyl peroxydicarbonate, t-
Organic peroxides such as butyl peroxy neodecanoate and α-cumyl peroxy neodecanoate; 2,
2-azobisisobutyronitrile, 2,2-azobis-
Azo compounds such as 2,4-dimethylvaleronitrile and the like can be mentioned. In the above suspension polymerization method, if necessary, pH
Adjusters, antioxidants and the like may be added.

Specifically, for example, a reaction vessel equipped with a stirrer and a jacket is charged with pure water, the acrylic copolymer (a), a dispersant, an oil-soluble polymerization initiator, and After the air in the polymerization vessel is discharged by a vacuum pump, and vinyl chloride (b) and, if necessary, other vinyl monomers are added under stirring conditions, the reaction vessel is charged. The inside is heated by a jacket to carry out graft copolymerization of vinyl chloride.

Since the above-mentioned graft copolymerization of vinyl chloride is an exothermic reaction, the temperature in the reaction vessel can be controlled by changing the jacket temperature. After the completion of the reaction, unreacted vinyl chloride is removed to form a slurry, and the slurry is dehydrated and dried to produce the vinyl chloride resin (A).

The rigid vinyl chloride resin tube of the present invention comprises 0.2 to 7 parts by weight of the heat stabilizer (B) and 0.2 parts by weight of stearic acid (C) based on 100 parts by weight of the vinyl chloride resin (A). 1
To 5 parts by weight, calcium stearate (D) 0.1 to 5
Parts by weight, and 0.1 to 10 parts by weight of a processing aid (E-1) having a weight average molecular weight of 60,000 or more and 0.1 to 1 part by weight of a processing aid (E-2) having a weight average molecular weight of less than 60,000. Can be obtained by subjecting a vinyl chloride resin composition obtained by blending the above to melt extrusion molding into a tube.

The heat stabilizer (B) is not particularly restricted but includes, for example, dibutyltin mercapto, dioctyltin mercapto, dimethyltin mercapto, dibutyltin malate,
Dibutyltin malate polymer, dioctyltin malate,
Organotin stabilizers such as dioctyltin malate polymer, dibutyltin laurate, dibutyltin laurate polymer; lead stabilizers such as lead stearate, dibasic lead phosphite, and tribasic lead sulfate; calcium-zinc Stabilizers; barium-zinc stabilizers; barium-cadmium stabilizers and the like. These may be used alone or in combination of two or more.

The heat stabilizer (B) is added in an amount of 0.2 to 7 parts by weight based on 100 parts by weight of the vinyl chloride resin (A). When the amount is less than 0.2 parts by weight, the thermal stability decreases, and extrusion molding becomes difficult. On the other hand, when the amount exceeds 7 parts by weight, the impact resistance and the heat resistance decrease. Is 0.4 to 5 parts by weight.

The heat stabilizer (B) may be used in combination with a stabilizing aid. The stabilizing aid is not particularly limited, and includes, for example, epoxidized soybean oil, epoxidized tetrahydrophthalate, epoxidized polybutadiene, and phosphate ester. These may be used alone or in combination of two or more.

Further, stearic acid (C) acts as an internal lubricant, is mainly used for the purpose of accelerating the gelation of the molten resin at the time of extrusion molding, lowering the flow viscosity and preventing frictional heat generation. There is no particular limitation. The mixing amount of stearic acid (C) is 100
It is 0.1 to 5 parts by weight with respect to parts by weight. When the amount is less than 0.1 part by weight, the appearance of the obtained resin tube is not good. On the contrary, when the amount exceeds 5 parts by weight, heat resistance is reduced. Parts by weight.

Also, calcium stearate (D)
It acts as an external lubricant and is used mainly for the purpose of improving the sliding effect between the molten resin and the metal surface during extrusion molding, and its grade is not particularly limited. The blending amount of the calcium stearate (D) is the same as that of the vinyl chloride resin (A).
0.1 to 5 parts by weight based on 100 parts by weight. 0.1
When the amount is less than 5 parts by weight, the appearance of the obtained resin tube is not good. On the contrary, when the amount exceeds 5 parts by weight, the build-up problem and the heat resistance at the time of long-term extrusion are reduced. Is 0.1 to 3 parts by weight.

The processing aid (E-1) is used for the purpose of improving the appearance of the obtained rigid vinyl chloride resin pipe, and its compounding amount is 100 parts of the above vinyl chloride resin (A).
0.1 to 10 parts by weight with respect to parts by weight. When the amount is less than 0.1 part by weight, the dispersibility is not good, it is difficult to promote the gelation of the resin uniformly, and the appearance of the obtained resin tube is not good. Therefore, it is limited to the above range.

The above-mentioned processing aid (E-2) is used for the purpose of improving running properties, and the amount thereof is 0.1 to 1 part by weight based on 100 parts by weight of the vinyl chloride resin (A). It is. When the amount is less than 0.1 part by weight, there is no effect. On the other hand, when the amount exceeds 1 part by weight, the lubrication is too strong and the balance between the appearance and the physical properties is deteriorated.

Examples of the processing aid include n-butyl acrylate-methyl methacrylate copolymer and 2-
Ethylhexyl acrylate-methyl methacrylate-
Butyl methacrylate copolymer and the like.

The vinyl chloride resin composition includes:
If necessary, other lubricants, plasticizers, antioxidants,
Additives such as an ultraviolet absorber, a light stabilizer, an antistatic agent, a filler, and a pigment may be added.

Other lubricants include montanic acid wax, paraffin wax, polyethylene wax, stearyl alcohol, butyl stearate and the like. Examples of the plasticizer include dibutyl phthalate, di-2-ethylhexyl phthalate, di-
2-ethylhexyl adipate and the like can be mentioned.

Examples of the antioxidant include phenolic antioxidants. Examples of the light stabilizer include hindered amine-based light stabilizers and the like. Examples of the ultraviolet absorbent include salicylic acid ester-based, benzobunone-based, benzotriazole-based, and cyanoacrylate-based ultraviolet absorbers. As the filler, for example, calcium carbonate,
Talc and the like. Examples of the pigment include organic pigments such as azo-based, phthalocyanine-based, sulene-based and dye lake-based pigments; oxide-based pigments, molybdenum chromate-based pigments, and sulfide-based pigments.
Inorganic pigments such as selenide and ferrocyanide are exemplified.

In the present invention, the heat stabilizer (B) is used in an amount of from 0.2 to 100 parts by weight of the vinyl chloride resin (A).
7 parts by weight, stearic acid (B) 0.1-5 parts by weight, calcium stearate (D) 0.1-5 parts by weight, processing aid (E-1) 0.1-10 parts by weight and processing aid 0.1-1 part by weight of an agent (E-2) is blended, and the resulting mixture is mixed by, for example, a hot blending method or a cold blending method to form a vinyl chloride resin composition. A rigid vinyl chloride resin tube is obtained by melt extrusion molding into a tube using a twin screw extruder. The conditions for the melt extrusion molding are the same as the conventional conditions.

[0041]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples.

(Examples 1 to 4, Comparative Examples 1 to 16) According to the latex formulation and polymerization formulation shown in Tables 1 and 2, the acrylic copolymer (a) and the vinyl chloride resin (A) ) Got. <Preparation of Acrylic Copolymer (a)> Into a reaction vessel equipped with a stirrer and a reflux condenser, pure water and an emulsifying dispersant (products manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Name "HITENOL N-08") (abbreviated as AS in the table), ammonium persulfate (abbreviated as APS in the table), n-butyl acrylate (abbreviated as BA in the table), and trimethylolpropane Triacrylate (in the table, TMP
TA), the oxygen in the vessel was replaced with nitrogen, and the temperature of the reaction vessel was raised to 65 ° C. under stirring conditions.
By heating and stirring for an hour, an acrylic copolymer (a) having a solid concentration of 30% by weight was obtained.

<Preparation of Vinyl Chloride Resin (A)> Then, the above-mentioned acrylic copolymer and partially saponified polyvinyl alcohol (A) were added to a reaction vessel equipped with a stirrer and a jacket in the amounts shown in Tables 1 and 2. 3% aqueous solution of Kuraray Co., Ltd., trade name "Kuraray Povar L-8" (abbreviated as PVA aqueous solution in the table), hydroxypropyl methylcellulose (Shin-Etsu Chemical Co., Ltd., trade name "Metroze 60SH5")
0 ") (in the table, abbreviated as cellulose aqueous solution), t-butyl peroxy neodecanoate (in the table,
BPOND), α-cumylperoxy neodecanoate (abbreviated as QPOND in the table), and C
aCl ₂ was charged all at once, then the air in the polymerization reactor was discharged by a vacuum pump, and vinyl chloride was further charged under stirring conditions. After stirring for 30 minutes, vinyl chloride was uniformly mixed, and jacket temperature was reduced. Polymerization was started at a polymerization temperature of 50 ° C. by control.

The completion of the reaction was confirmed by reducing the pressure in the reactor to a pressure of 5.8 kg / cm ² , and after the defoaming agent (manufactured by Toray Industries, Inc., “Toray Silicon SH5510”) was added under pressure, the reaction was stopped. Stopped. Thereafter, the unreacted vinyl chloride monomer was removed, followed by dehydration drying to obtain a vinyl chloride resin (A).

According to the blending and extrusion conditions shown in Tables 3 to 6, a rigid vinyl chloride resin tube of the present invention was obtained by the following procedure. <Manufacture of hard vinyl chloride resin tube> A heat stabilizer (B) (trade name "SNT-461K", manufactured by Sankyokisei Co., Ltd., an organic tin stabilizer) was added to 100 parts by weight of the vinyl chloride resin (A). ), Polyethylene-based lubricant (trade name “Hiwax220RKT”, polyethylene wax, manufactured by Mitsui Petrochemical Co., Ltd.), stearic acid (B) (trade name “S-3, manufactured by Kao Corporation”)
0C "), calcium stearate (D) (manufactured by Sakai Chemical Co., trade name" SC-100C "), and a processing aid (E-1) having a weight average molecular weight of 60,000 or more (manufactured by Mitsubishi Rayon Co., Ltd., trade name" METABLEN P-501A ") and a processing aid (E-2) having a weight average molecular weight of less than 60,000 (trade name" METABLEN P-700 "manufactured by Mitsubishi Rayon Co., Ltd.)
The obtained resin composition was supplied to a 50 mm-diameter biaxially different direction extruder (trade name “SLM-50” manufactured by Nagata Seisakusho Co., Ltd.) to obtain a hard vinyl chloride resin tube having a diameter of 20 mm.
In Comparative Examples 7 and 8, a vinyl chloride resin having a polymerization degree of 1400 was used in place of the vinyl chloride resin (A).

<Evaluation of Physical Properties of Hard Vinyl Chloride Resin Tube> The physical properties of the vinyl chloride resin and the hard vinyl chloride resin tube were evaluated by the following methods. The results are summarized in Tables 3 to 6. (1) Degree of polymerization The viscosity average degree of polymerization of the vinyl chloride resin (A) was measured in accordance with JIS K 6721, and the degree of polymerization was defined as the degree of polymerization. (2) Impact resistance In accordance with JIS K 6742, a rigid vinyl chloride resin tube was subjected to a falling weight impact test at 0 ° C. and −10 ° C. The unit is cm. Further, in accordance with JIS K 7110, an Izod impact test at 23 ° C. was performed on a notched test piece. The unit is kg · cm / cm ² .

(3) Exposure test 60, 120, 18 in accordance with JIS A1415
After the exposure for 0 and 240 hours, the test piece was subjected to an Izod impact test at 23 ° C. (4) Tensile strength A tensile strength test at 23 ° C. was performed according to JIS K 7113. The unit is kg / cm ² .

(5) Vigat Softening Temperature A vigat softening temperature test was carried out in accordance with JIS K7206. The unit is ° C. (6) Appearance The surface condition (gloss and smoothness) of the rigid vinyl chloride resin tube was visually evaluated. (7) Running properties The surface condition (gloss and smoothness) of the rigid vinyl chloride resin tube after 24 hours of continuous extrusion was evaluated.

[0049]

[Table 1]

[0050]

[Table 2]

[0051]

[Table 3]

[0052]

[Table 4]

[0053]

[Table 5]

[0054]

[Table 6]

[0055]

The rigid vinyl chloride resin tube of the present invention has the above-mentioned structure, and has a specific polymerization degree obtained by graft-polymerizing a specific amount of vinyl chloride to a specific acrylic copolymer (a). Using resin (A), specific amounts of heat stabilizer (B), stearic acid (C), calcium stearate (D), and processing aid (E-1) having a weight average molecular weight of 60,000 or more and weight A vinyl chloride-based resin composition containing a processing aid (E-1) having an average molecular weight of less than 60,000,
It is obtained by melt extrusion molding into a tube, and is excellent in impact resistance, mechanical strength, and heat resistance without adding a conventional impact resistance reinforcing agent. In addition, it is required to have excellent impact resistance after the exposure test, as well as excellent surface condition (gloss and smoothness) and running performance of extrusion molding, durability, weather resistance, impact resistance, heat resistance and excellent appearance. Building materials, plumbing equipment,
It is suitably used for housing materials and the like.

The vinyl chloride resin composition used for producing the rigid vinyl chloride resin tube of the present invention has a wide extrusion molding temperature range, good heat stability and fluidity, a low extrusion load, and a normal extrusion load. Melt extrusion molding is possible.

Claims (1)

[Claims] The glass transition temperature of the homopolymer is -20.
Alkyl (meth) acrylate monomer having a temperature of less than 80 ° C.
100% by weight and the glass transition temperature of the homopolymer is -20
Acrylic obtained by copolymerizing 100 parts by weight of an acrylic mixed monomer (a-1) composed of 20 to 0% by weight of a monomer having a temperature of at least 0 ° C. and 0.1 to 10 parts by weight of a polyfunctional monomer (a-2). System copolymer (a) 3 to 10% by weight
The degree of polymerization obtained by graft copolymerizing 97 to 90% by weight of vinyl chloride (b) by suspension polymerization is 800 to
0.2 to 7 parts by weight of heat stabilizer (B), 0.1 to 5 parts by weight of stearic acid (C), and 0.1 to 5 parts by weight of calcium stearate (D) per 100 parts by weight of 2,000 vinyl chloride resin (A). 1 to 5 parts by weight, and a weight average molecular weight of 6
10,000 or more processing aids (E-1) 0.1 to 10 parts by weight and processing aids (E-2) having a weight average molecular weight of less than 60,000 0.1 to 1
A rigid vinyl chloride-based resin pipe obtained by melt-extruding a vinyl chloride-based resin composition containing parts by weight into a tubular shape.