JPH10287782A - Heat-resistant vinyl chloride resin composition and heat-resistant vinyl chloride resin welding rod - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a composition having excellent welding strength by mixing an impact modifier comprising a chlorinated vinyl chloride resin, a chlorinated polyethylene and/or a methyl methacrylate/butadiene/styrene copolymer and an alkyltin mercapto compound and/or an alkyltin maleate compound. SOLUTION: This composition comprises 2-20 pts.wt. impact modifier comprising 100 pts.wt. chlorinated vinyl chloride resin having a chlorine content of 59-71 wt.% and an average degree of polymerization of 40-1,000 (before chlorination) and a chlorinated polyethylene having a degree of chlorination of 30-40 wt.% and/or methyl methacrylate/butadiene/styrene copolymer and 2-8 pts.wt. alkyltin mercapto compound and/or alkyltin maleate compound. The alkyltin mercapto compound is exemplified by a polymer comprising a 1-10C alkyl).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a heat-resistant vinyl chloride resin composition and a heat-resistant vinyl chloride resin welding rod using the same.

[0002]

2. Description of the Related Art Conventionally, vinyl chloride resin molded products have been
Utilizing excellent properties such as mechanical strength, chemical resistance, oil resistance and the like, it is used for pipes, joints, flat plates, etc. for building materials, water supply, agriculture, industry, etc. Further, the vinyl chloride resin molded product is also used for applications requiring heat resistance. However, the heat resistance of a vinyl chloride resin molded product cannot be said to be sufficient, and improvement in heat resistance has been studied.

As a method for improving the heat resistance of a vinyl chloride resin molded product, a method of post-chlorinating a vinyl chloride resin to obtain a chlorinated vinyl chloride resin is generally used. Chlorinated vinyl chloride resin molded products obtained by post-chlorination, for example, hot water pipes, fire extinguishing sprinkler piping materials, industrial piping materials, industrial boards, etc., can not be used in conventional vinyl chloride resin molded products It can be used in various fields and environments.

However, when a conventional molded article made of a vinyl chloride resin molded article is used for a welding rod of a chlorinated vinyl chloride resin molded article, for example, the welding strength is low, the thermal stability is low, and the impact resistance is low. For example, there is a problem that a welded portion is easily cracked or broken due to low weldability, and sufficient weldability cannot be obtained.

In order to improve the weldability and impact resistance of a welding rod, for example, Japanese Unexamined Patent Publication (Kokai) No. 53-148551 discloses that a terpolymer of ethylene-vinyl acetate-vinyl chloride is mixed with a vinyl chloride resin. A method for doing so is disclosed. However, when the above mixture is used as a welding rod for a chlorinated vinyl chloride resin molded product, the glass transition temperature between the welding rod and the chlorinated vinyl chloride resin molded product is significantly different, and sufficient welding strength cannot be obtained. There was a point.

Further, as a resin composition for improving the heat resistance of a welding rod, for example, Japanese Patent Application Laid-Open No. Hei 8-113885 discloses a heat-resistant vinyl chloride resin composition. However, this resin composition cannot be said to have sufficient weldability depending on the application, and has a problem that the welding time is prolonged or sufficient welding strength cannot be obtained.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks, and it is an object of the present invention to provide excellent heat resistance, chemical resistance, and sufficient welding strength. And to provide a heat-resistant vinyl chloride-based resin composition and a heat-resistant vinyl chloride-based resin welding rod using the same.

[0008]

[Means for Solving the Problems]

The heat-resistant vinyl chloride resin composition of the present invention comprises an impact modifier comprising a chlorinated vinyl chloride resin, a chlorinated polyethylene and / or a methyl methacrylate-butadiene-styrene copolymer, and an alkyltin mercapto compound. And / or an alkyltin malate compound.

As the vinyl chloride resin before chlorination used for the chlorinated vinyl chloride resin, those which have been known can be used. For example, a homopolymer of vinyl chloride; vinyl chloride And a copolymer of a polymerizable monomer having an unsaturated bond copolymerizable with the vinyl chloride;
Examples include a graft copolymer obtained by grafting vinyl chloride to a polymer other than vinyl chloride, and these may be used alone or in combination of two or more.

The polymerizable monomer having an unsaturated bond is not particularly limited, and includes, for example, α-olefins such as ethylene, propylene and butylene; vinyl esters such as vinyl acetate and vinyl propionate; butyl vinyl ether and cetyl Vinyl ethers such as vinyl ether;
(Meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl acrylate and phenyl methacrylate; aromatic vinyls such as styrene and α-methylstyrene; N-phenylmaleimide, N-cyclohexylmaleimide and the like N-substituted maleimides, etc., may be used alone or in combination of two or more.

The polymer for graft copolymerization of the above vinyl chloride is not particularly limited. For example, ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-carbon monoxide copolymer, ethylene-ethyl acrylate copolymer Coalescence, ethylene-butyl acrylate-carbon monoxide copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, acrylonitrile-butadiene copolymer, polyurethane, chlorinated polyethylene, chlorinated polypropylene, etc. These may be used alone or in combination of two or more.

The chlorinated vinyl chloride resin (hereinafter referred to as CP)
VC), as the average degree of polymerization of the vinyl chloride resin before chlorination decreases, the welding strength and physical properties decrease, and as the average polymerization degree increases, the workability and welding strength decrease. The average degree of polymerization of the resin is 400 to
1,000 is preferable, and more preferably 600 to 800.
It is.

If the chlorine content of the above-mentioned CPVC is too low, sufficient heat resistance cannot be obtained, and if it is too high, the workability deteriorates. Therefore, the chlorine content is limited to 59 to 71% by weight, preferably 64.
７０70% by weight. The chlorine content is determined by the required heat resistance, and various chlorination methods, such as a conventionally known water suspension method and a solution chlorination method, are used. Among them, the water suspension method is industrially preferable.

In order to improve the impact resistance of the CPVC, chlorinated polyethylene (hereinafter, referred to as CPE) or methyl methacrylate-butadiene-styrene copolymer (hereinafter, referred to as MBS) is used alone or both. Are used together.

When the weight-average molecular weight of the CPE is small, the impact strength of the molded article decreases, and when it is large, the effect of improving the impact strength of the molded article is not exhibited.
~ 400,000, more preferably 150,
000-350,000. The weight average molecular weight is a value in terms of polystyrene measured by GPC.

The chlorination degree of the above CPE is limited to 30 to 40% by weight because a lower chlorination degree adversely affects the physical properties of the molded article, and a higher chlorination degree does not exhibit the effect of improving the impact resistance.

When the amount of the CPE used is small, the effect of improving the impact resistance is not exhibited, and when the amount is large, the heat resistance is reduced or the welding strength is reduced. Is limited to

The MBS may be an impact modifier used for ordinary vinyl chloride resin, for example, "BTA" manufactured by Kureha Chemical Industry Co., Ltd., "B-56" manufactured by Kaneka Chemical Industry Co., Ltd., "Mitsubishi Rayon Co., Ltd." METABLEN C "and the like are commercially available products.

When the amount of the MBS used is small, the effect of improving the impact resistance is not exhibited, and when the amount is large, the moldability is reduced and the chemical resistance to acids and alkalis is reduced.
It is limited to 2 to 20 parts by weight based on 100 parts by weight of CPVC.

When the amount of the above-mentioned CPE and MBS is used in combination, the effect of improving the impact resistance of the molded body is not exhibited when the amount is small, and the heat resistance and chemical resistance are decreased when the amount is large, and the moldability is increased. Worsens and leads to higher costs.
The total amount of both is limited to 2 to 20 parts by weight based on 100 parts by weight of VC.

The alkyltin mercapto compound is a compound represented by the general formula (1) or a polymer having a repeating unit represented by the general formula (2).

[0023]

Embedded image

In the formula (1), R ¹ , R ² , R ³ , R
⁴ is independently an alkyl group having 1 to 10 carbon atoms, -SR ^a
Or -S (CH ₂₎ shows the _m COOR ^a, R a represents an alkyl group having 2 to 24 carbon atoms, m is an integer of 1 or more. The alkyl group represented by R ^{1 to} R ⁴ is preferably a methyl group, a butyl group, an octyl group and the like, and the alkyl group represented by R ^a is preferably an alkyl group having 11 to 17 carbon atoms.

[0025]

Embedded image

In the formula (2), R ⁵ and R ^{6 each} independently represent an alkyl group having 1 to 10 carbon atoms, and 1 is an integer of 1 or more. As the alkyl group represented by R ⁵ and R ⁶ , a methyl group, a butyl group, an octyl group and the like are preferable.

Specific examples of the alkyltin mercapto compound include a dialkyltin dialkylmercaptide represented by the general formula (3) and a dialkyltin bis (alkyl mercaptocarboxylate) represented by the general formula (4). And a salt, a dialkyltin mercaptocarboxylate polymer having a repeating unit represented by the general formula (5), and the like.

[0028]

Embedded image

[0029]

Embedded image

[0030]

Embedded image

In the formulas (3) to (5), R represents 1 to 10 carbon atoms.
R ¹⁶ and R ¹⁷ each represent an alkyl group having 2 to 24 carbon atoms, and m and n each represent an integer of 1 or more.

The alkyltin malate compounds include:
A compound represented by the general formula (6), a polymer having a repeating unit represented by the general formula (7), or a compound represented by the general formula (8).

[0033]

Embedded image

In the formula (6), R ⁷ , R ⁸ , R ⁹ , R
¹⁰ is independently an alkyl group having 1 to 10 carbon atoms or -OC
OCH = CHCOOR ^b , wherein R ^b has 2 to 2 carbon atoms
4 represents an alkyl group, preferably an alkyl group having 11 to 17 carbon atoms.

[0035]

Embedded image

In the formula (7), R ¹¹ and R ¹² independently represent an alkyl group having 1 to 10 carbon atoms, preferably a methyl group, a butyl group and an octyl group.

[0037]

Embedded image

In the formula (8), R ¹³ has 1 to 1 carbon atoms.
0 represents an alkyl group, and R ¹⁴ and R ¹⁵ independently represent an alkyl group having 2 to 24 carbon atoms.

The alkyltin malate compounds include:
Specifically, a dialkyltin bis (maleic acid alkyl ester) salt represented by the general formula (9), a bis (dialkyltin maleic acid alkyl ester) maleate represented by the general formula (10), a general formula (11) And a dialkyltin maleate polymer having a repeating unit represented by formula (1).

[0040]

Embedded image

[0041]

[Formula 10]

[0042]

[Formula 11]

In the above formulas (9) to (11), R ¹⁸ , R
¹⁹ independently represents an alkyl group having 2 to 24 carbon atoms.

In the heat-resistant vinyl chloride resin composition of the present invention, at least one of the above-mentioned alkyltin mercapto compounds and alkyltin malate compounds is used, and two or more thereof may be used in combination.

When the amount of the above-mentioned alkyltin mercapto compound and / or alkyltin malate compound is small, the heat stabilizing effect is reduced, and when the amount is large, the heat resistance is remarkably reduced. Therefore, based on 100 parts by weight of the chlorinated vinyl chloride resin. 2 to 8 parts by weight.

If necessary, an alkyltin laurate compound such as dibutyltin laurate may be used in combination with the above-mentioned alkyltin mercapto compound and / or alkyltin malate compound. 0.1 to 4 parts by weight is preferable for 100 parts by weight.

The heat-resistant vinyl chloride resin composition includes:
If necessary, di-2-ethylhexyl phthalate (DO
P), plasticizers such as 2-ethylhexyl adipate (DOA); paraffin wax, polyethylene wax, polypropylene wax, ester wax,
Lubricants such as stearic acid, montanic acid-based wax, calcium stearate; pigments; fillers such as calcium carbonate and glass fiber; and antistatic agents, flame retardants, processing aids, and the like may be added.

The heat-resistant vinyl chloride-based resin composition comprises the chlorinated vinyl chloride-based resin, the CPE and / or the MB.
It can be obtained by mixing S, the above-mentioned alkyltin mercapto compound and / or alkyltin malate compound, and other additives with a usual mixing device, for example, a Henschel mixer.

For molding the above-mentioned heat-resistant vinyl chloride resin composition, a known method is employed, for example, an extrusion molding method using a single-screw or twin-screw extruder, an injection molding method and the like. Heat-resistant vinyl chloride resin welding rod, for example,
It is obtained by extruding the above heat-resistant vinyl chloride resin composition.

[0050]

Next, embodiments of the present invention will be described. (Examples 1 to 9, Comparative Examples 1 to 6) A predetermined amount of chlorinated vinyl chloride resin shown in Tables 1 and 2 ["H" manufactured by Tokuyama Sekisui Industry Co., Ltd.
A-05H ", average degree of polymerization 500, chlorine content 65% by weight), (" HA-24K ", average degree of polymerization 700, chlorine content 67% by weight) or (" HA-51K ", average degree of polymerization 1, 000, chlorine content 67% by weight), vinyl chloride resin ("TS-1000R" manufactured by Tokuyama Sekisui Kogyo Co., Ltd., average degree of polymerization 1,000), CPE ("JMR135 manufactured by Daiso Corporation")
C ") and / or MBS (" BTA-
751 "), an alkyltin mercapto compound and / or an alkyltin malate compound, 1 part by weight of stearic acid (" Sakurain stearic acid "manufactured by NOF Corporation), and a polyethylene-based lubricant (" Hiwax220M "manufactured by Mitsui Petrochemical Co., Ltd.)
P ”) was heated to 100 ° C. in a Henschel mixer and mixed to prepare a resin composition. The resin composition was supplied to a 30 mm twin-screw extruder to extrude a welding rod having a diameter of 3 mm at a resin temperature of 190 ° C. Molded. In addition, the above resin composition was heated at 200 ° C.
The mixture was kneaded with a mixing roll for about 3 minutes to obtain a sheet, and then press-formed at 210 ° C. and 150 kg / cm ² for 4 minutes to prepare a plate having a thickness of 3 mm.

With respect to the welding rods and plates obtained in the above Examples and Comparative Examples, the following performance evaluations (1) to (7) were carried out, and the results are shown in Tables 1 to 3. (1) Softening Temperature The Vicat softening temperature of the plate was measured according to JIS K7206. (2) Impact strength The Charpy impact strength of the plate was measured according to JIS K7110. (3) Alkali resistance 30% by weight N at 90 ° C.
The weight change rate after immersion in an aOH aqueous solution for 60 days was measured. (4) Acid Resistance The weight change rate after immersing the welding rod cut to a length of 10 cm in a 40% by weight nitric acid aqueous solution at 60 ° C. for 60 days was measured. (5) Thermal Stability A welding rod cut to a length of 3 cm was placed in a 210 ° C. gear oven and the time until blackening was measured. (6) Workability Hot air of 230 ° C. was blown from a hot jet gun to a welding rod having a length of 1 m to weld axially on a polyvinyl chloride resin pipe having a diameter of 50 mm, and a welding speed per 1 m was measured. (7) Weld strength Two 5 mm thick heat-resistant vinyl chloride resin plates (Sekisui Chemical Co., Ltd. "Ethlon HT plate") with chamfered edges
Were welded in three layers by blowing hot air at 230 ° C. onto a welding rod from a hot jet gun, and then measuring the welding strength by tensile strength.

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

[Table 3]

[0055]

The constitution of the heat-resistant vinyl chloride resin composition of the present invention is as described above, and it can be easily molded by a usual method for molding a chlorinated vinyl chloride resin, and is obtained from the resin composition. Since the welding rod has good weldability, and excellent heat resistance and chemical resistance, it can be suitably used as a welding material for plant piping in fields where heat resistance and chemical resistance are required. .

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 23:28 33:12) B29K 27:06

Claims (2)

[Claims] 1. A chlorine content of 59 to 71% by weight, and an average degree of polymerization of a vinyl chloride resin before chlorination is 400 to 1,000.
0 to 100 parts by weight of a chlorinated vinyl chloride resin, 2 to 20 parts by weight of an impact modifier comprising a chlorinated polyethylene having a chlorination degree of 30 to 40% by weight and / or a methyl methacrylate-butadiene-styrene copolymer, and A heat-resistant vinyl chloride resin composition comprising 2 to 8 parts by weight of an alkyltin mercapto compound and / or an alkyltin malate compound. 2. A heat-resistant vinyl chloride-based resin welding rod formed from the heat-resistant vinyl chloride-based resin composition according to claim 1.