JP2912950B2 - PVC resin composition - Google Patents

Description

The present invention relates to a vinyl chloride resin composition suitable for applications requiring rubber elasticity.

[Problems to be solved by conventional technology and invention]

Conventionally, methods for improving the rubber elasticity of vinyl chloride resins include, for example, organic peroxides such as benzoyl peroxide, dicumyl peroxide, and t-butyl peroxide, for example, 1,4-tetramethylenediamine, 1,6- A method by crosslinking a vinyl chloride resin with a diamine compound such as hexamethylene diamine or a sulfur compound such as sulfur, tetramethyl turam disulfide or triazine thiol, a method by crosslinking components such as diallyl phthalate, a crosslinkable polyurethane or an epoxy resin, Further, a method of blending a cross-linked vinyl chloride resin or a cross-linked polyurethane having good compatibility with the vinyl chloride resin which has been cross-linked at the time of polymerization with the vinyl chloride resin, or using a vinyl chloride resin having a reactive group such as a hydroxyl group, using a diisocyanate, etc. How to Etc. there is.

In these methods, when a vinyl chloride resin is crosslinked, a rubber-like elastic body can be easily obtained, but on the other hand, (1) poor thermal stability and easy to color (2) residue of a crosslinking agent (3) If the degree of crosslinking is increased, there is a problem that a large amount of a plasticizer is required to obtain a predetermined hardness.

When a reactive plasticizer is used, the same problem as described above occurs because it is often a radical reaction system. In a method of blending a crosslinked vinyl chloride resin or a crosslinked polyurethane having good compatibility with the vinyl chloride resin with the vinyl chloride resin, (1) poor moldability (2) it is difficult to obtain a product having low compression set (3) cost increase, etc. There's a problem. Further, in a method of using a vinyl chloride resin having a hydroxyl group to form a crosslinked product with diisocyanate or the like, it is difficult to obtain desired elasticity due to poor reactivity.

In recent years, a composite of a vinyl chloride resin and a polyurethane has attracted attention, and various methods have been proposed. For example, a method of dissolving polyurethane in vinyl chloride monomer (VCM) and obtaining a composite of vinyl chloride resin and polyurethane by polymerization of VCM, and manufacturing a hydroxyl group-containing vinyl chloride resin by polymerization of VCM in the presence of a polyol. Examples of the method include a method obtained by a urethanization reaction, and a method obtained by impregnating a vinyl chloride resin with a polyol, an isocyanate, a catalyst, and the like, and reacting.

However, the composites of the vinyl chloride resin and polyurethane obtained by these methods are inferior in rubber elasticity and are not suitable for applications requiring rubber elasticity.

In such a method for producing a composite, when a urethane crosslinked product is produced using triisocyanate, the processability becomes poor. There is also a method in which a vinyl chloride resin and a polyurethane elastomer having high elasticity are polymer-blended in a roll or a Banbury mixer to obtain a composite of the vinyl chloride resin and polyurethane. Although the composite obtained by this method is excellent in rebound resilience, it is inferior in compression set, and thus improvement is desired.

[Means for solving the problem]

The present inventors have studied the high elasticity vinyl chloride resin in view of the above-mentioned current situation, and have completed the present invention.

That is, the present invention is a vinyl chloride resin obtained by heating and melting and mixing a vinyl chloride resin, a compound having two or more hydroxyl groups and a polymer polyol having a molecular weight of 300 to 10,000 and a compound having three or more isocyanate groups under shearing force. A resin composition, wherein the amount of bound acrylonitrile is 25 to 50% by weight and the amount of tetrahydrofuran is 100 parts by weight based on 100 parts by weight of a vinyl chloride resin composition having a tetrahydrofuran (THF) -insoluble content of 5 to 55% by weight. 10 crosslinked acrylonitrile-butadiene copolymer (NBR) having an insoluble content of 60 to 95% by weight
The present invention relates to a vinyl chloride resin composition containing not less than 200 parts by weight and not more than 200 parts by weight of a vinyl chloride resin composition having a tetrahydrofuran insoluble content of 10 to 80% by weight.

 Hereinafter, the present invention will be described in detail.

The vinyl chloride resin used in the present invention may be a resin obtained by a commonly used polymerization method such as a suspension polymerization method, a bulk polymerization method, a solution polymerization method, and an emulsion polymerization method.

In the present invention, the vinyl chloride resin refers to a homopolymer of vinyl chloride and a copolymerized vinyl chloride resin with a monomer copolymerizable with a vinyl chloride monomer. Further, a vinyl chloride resin having a degree of polymerization of 800 to 8000, preferably 1,000 to 5,000 is used.

Examples of the monomer copolymerizable with the vinyl chloride monomer include ethylene, propylene, butene, pentene-1, butadiene, styrene, α-methylstyrene, acrylonitrile, vinylidene chloride, vinylidene cyanide, alkyl vinyl ethers, and carboxylic acid. Examples thereof include vinyl esters, aryl ethers, dialkylmaleic acids, fumaric esters, N-vinylpyrrolidone, vinylpyridine, vinylsilanes, alkyl acrylates, and alkyl methacrylates. Further, the vinyl chloride resin may be a graft polymer such as an ethylene-vinyl acetate-vinyl chloride graft polymer and a vinyl chloride urethane copolymer. However, the vinyl chloride resin is not limited to these. A crosslinked vinyl chloride resin obtained by adding a divinyl compound such as divinylbenzene during the polymerization of these polymers is also used. Cross-linked vinyl chloride resin is tetrahydrofuran (TH
F) The insoluble content is in the range of 0.1 to 25% by weight by weight, and is used alone or in a blend with an uncrosslinked vinyl chloride resin.

The polymer polyol used in the present invention has two or more hydroxyl groups, and has a molecular weight of 300 or more and 10,000 or less, preferably 1000 or less.
More than 5000. Such polymer polyols include, for example, aliphatic glycols having 4 to 10 carbon atoms and aliphatic glycols having 2 to 10 carbon atoms and / or glycols having 5 or less repeating units obtained by ring-opening polymerization of epoxy groups. It can be obtained by condensation polymerization. In the present invention, the molecular weight refers to a number average molecular weight, which can be measured by gel permeation chromatography (GPC) or the like.

Examples of the glycol used for producing the polymer polyol include, for example, 1,2-ethanediol, 1,2-propanediol, 1,4-butanediol, butenediol,
Methyl-1,5-pentanediol, 1,6-hexadiol, 1,10-decamethylenediol, 2,5-dimethyl-2,5
-Hexanediol, neopentyl glycol, 1,4-
Cyclohexane dimethanol and the like.

On the other hand, compounds having an epoxy group include, for example, ethylene oxide, propylene oxide, tetrahydrofuran (TH
A glycol having a repeating unit of 5 or less obtained by ring-opening polymerization of a cyclic ether such as F) may be used. One of these
Species or two or more are used.

4 to 10 carbon atoms used in the production of polymer polyols
Examples of the aliphatic dicarboxylic acids include succinic acid, glutaric acid, adipic acid, azelaic acid, and sebacic acid, and one or more of these are used. Such a polyol is commercially available from Nippon Polyurethane Co., Ltd. under the trade name Nipporan.

The addition amount of the polymer polyol is preferably 10 to 170 parts by weight based on 100 parts by weight of the vinyl chloride resin. If the amount is less than 10 parts by weight, the rubber elasticity is not improved, and if the amount exceeds 170 parts by weight, processing becomes impossible.

The compound having three or more isocyanate groups used in the present invention includes, for example, 2,4- and 2,6-tolylene diisocyanate, m- and p-phenylene diisocyanate,
-Chlorophenylene-2,4-disocyanate, 1,5-naphthalenediisocyanate, methylenebisphenylene-4,
Trimers of diisocyanates such as 4'-diisocyanate, m- and p-xylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, 4,4'-methylenebiscyclohexyl diisocyanate, isophorone diisocyanate and trimethylhexamethylene diisocyanate; Triisocyanates such as -undecane triisocyanate, lysine ester triisocyanate, 4-isocyanatomethyl-1,8-octamethyl diisocyanate, or polyfunctional isocyanates such as polyphenylmethane polyisocyanate; Two or more are used. However, the NCO group mole number of the triisocyanate to the NCO group mole number of all isocyanates is preferably 0.25 or more,
If it is less than 0.25, sufficient performance cannot be exhibited due to insufficient crosslinking density. Further, the NCO / OH ratio is preferably in the range of 0.3 to 1.3. 0.
If it is less than 3, even if triisocyanate is used as the isocyanate, sufficient performance cannot be exhibited due to insufficient crosslinking density, and if it exceeds 1.3, processing becomes difficult.

As the crosslinked NBR (acrylonitrile-butadiene copolymer) used in the present invention, the polymerization fraction of acrylonitrile in the polymer (the amount of bound acrylonitrile) is 25 to 50% by weight, and the THF-insoluble content is 60 to 95% by weight. Some are used. The production of the crosslinked NBR is not particularly limited as long as it is carried out according to the method of polymerizing a synthetic rubber. For example, in the emulsion copolymerization of butadiene and acrylonitrile, an alkylbenzene sulfonate, an alkyl sulfate, a disproportionated rosinate, a fatty acid salt, or the like is used as an emulsifier and polymerized, and in the polymerization, butadiene 50 to 75% by weight is used. %, Acrylonitrile 25 to 50% by weight. Such a polymerization method is described, for example, in JP-A-61-1927.
54, 61-192755. If the amount of bound acrylonitrile is out of the range of 25 to 50% by weight, the compatibility at the interface with the vinyl chloride resin is poor, and the compression set becomes large. THF
If the insoluble content is less than 60% by weight, the rubber elasticity is not improved, and the best content is 60 to 95% by weight in consideration of workability.

There is no limitation on the use of the plasticizer in the present invention. Examples of the plasticizer that can be used in the present invention include di-n-butyl phthalate, di-n-ethylhexyl phthalate (DOP), di-n-octyl phthalate, diisooctyl phthalate, octyldecyl phthalate, and diisodecyl phthalate. Phthalic acid plasticizers such as butylbenzyl phthalate and di-2-ethylhexyl isophthalate;
-Ethylhexyl (DOA), di-n-decyl adipate diisodecyl adipate, dibutyl sebacate, di-2-ethylhexyl sebacate, aliphatic ester plasticizer, tributyl phosphate, tri-2-ethylhexyl phosphate, phosphoric acid Examples thereof include phosphate plasticizers such as 2-ethylhexyldiphenyl and tricresyl phosphate, and epoxy plasticizers such as epoxidized soybean oil and epoxidized linseed oil. One or more of these are used.

Compositions having so-called high resilience and high rubber elasticity with little compression set include, for example, di-n-butyl phthalate, di-2-ethylhexyl phthalate (DOP) and di-2-ethylhexyl adipate (DOA). It is desired to use a plasticizer having a low molecular weight and a high plasticizing efficiency for vinyl chloride resin. If oil resistance and heat resistance are required, avoid using low molecular weight plasticizers and NCO / OH of urethane component.
If the ratio is 0.3 to 0.8, or a plasticizer is used, a phthalic acid or adipic acid polymer plasticizer is used.

In the present invention, a stabilizer can also be added to the vinyl chloride resin. As a stabilizer, for example, lead stearate,
Metallic soap stabilizers such as calcium stearate, barium stearate, zinc stearate, and cadmium stearate; and epoxy stabilizers such as epoxidized soybean oil and epoxidized linseed oil. Further commonly used UV absorbers, antioxidants, antioxidants, if necessary,
Processing aids, fillers and the like can also be blended. In the present invention, when a tin-based stabilizer is used, it serves as a catalyst for hydrolyzing the ester-based polymer polyol. In addition to the above, a resin having high rebound resilience, such as a polyurethane elastomer or a polyester elastomer, can be added to increase rebound resilience. There is no restriction on the amount added. The composition of the present invention is used in a kneader capable of shearing and melting a resin, such as a roll forming machine, a twin-screw kneader, an extruder, and a Banbury mixer. More specifically, for example, taking a Banbury mixer as an example, first, at a casing temperature of 100 to 200 ° C., a vinyl chloride resin and an ultraviolet absorber, an antioxidant, an antioxidant, an antioxidant, a processing aid, which are ordinarily used as necessary, Add filler and mix. Next, the polyol plasticizer and the isocyanate catalyst, which are kept warm at 50 to 80 ° C. in advance, are weighed and mixed, and charged from the inlet of the Banbury mixer. The temperature is set to 100 ° C. to 200 ° C. while applying a shearing force, and further, the heating and mixing are continued, and the vinyl chloride resin is melted and urethanized.
Remove after 3-60 minutes. Cross-linked NBR is better placed in a Banbury mixer at the same time as the vinyl chloride resin, as it has better dispersibility and better post-processing properties, but it may be placed in a roll forming machine to form a sheet.

The composition of the present invention should have a THF-insoluble content of 10 to 80% by weight. If the insoluble content is less than 10% by weight, sufficient compression set cannot be given, and if it exceeds 80% by weight, molding becomes difficult.

The method for measuring the THF-insoluble content in the present invention is as follows. In other words, a roll sheet with a thickness of 1.0
Cut to 1.5mm square and weigh 1.0g. This is placed in a 300 cc beaker and stirred with a stirrer in 200 ml THF for 2 hours. Although the sample swells with THF, it is filtered through a 300-mesh sieve, crushed with a glass rod or the like, and the filtrate is further stirred for 4 hours with a stirrer in 200 ml of THF. This solution is filtered through a filter paper which has been weighed in advance to separate insoluble components, the insoluble components and the filter paper are placed in a chalet, dried in an oven at 40 ° C. for 5 hours, and then weighed. The weight percentage of THF insolubles is determined from the weight of insolubles obtained by this method.
The ratio between the urethane component and the NBR component in the THF-insoluble matter can be determined as an absorption intensity ratio in an infrared absorption spectrum (IR).

〔Example〕

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited thereto.

Example 1 A vinyl chloride resin (manufactured by Tosoh Corporation, trade name "Ryuron E-2800") obtained by a suspension polymerization method was placed in a Banbury mixer having an internal volume of 1700 cc and a casing temperature of 150 ° C.
g, cross-linked NBR (bonded acrylonitrile amount 40%, THF insoluble matter 8
3%) 200g, barium stearate 9.6g as stabilizer,
4.3 g of zinc stearate and 6 g of a product name “BP-331” manufactured by Nissan Ferro-Organic Chemical Co., Ltd. as an amine scavenger were charged and stirred at a constant rotation speed. Separately, 280 g of a polyol (trade name “Nipporan 4067” manufactured by Nippon Polyurethane Co., Ltd.), which has been previously kept at 70 ° C., and 360 g of di-2-ethylhexyl phthalate (DOP) are mixed and mixed with hexamethylene Triisocyanate of diisocyanate (Nippon Polyurethane Co., Ltd.)
46.9 g (trade name “Coronate EH”) (NCB / OH ratio: 1) and 0.02 g of dibutyltin dilaurate as a catalyst were charged and mixed for 1 minute, and then poured from the inlet of the Banbury mixer. These mixing and reaction were carried out for 15 minutes.

After completion of the reaction, the obtained composite was rolled into a sheet, and then the thickness was 12.70 ± 0.13 mm for JIS K6301 compression set.
Press molding was performed so that Subsequently, the compression set (JISK6301) and the JISA type hardness (JISK6301) of the obtained pressed plate were measured. Table 1 shows the results.

(Example 2) Except that the crosslinked NBR was changed to 400 g, production and evaluation were performed in the same manner as in Example 1. Table 1 shows the results.

(Comparative Example 1) 1 kg of the vinyl chloride resin used in Example 1 in a Henschel mixer, 24 g of barium stearate, and 10.8 of zinc stearate
g and DOP of 1.1 kg, heat-stir, dry-up at 120 ° C., press-mold the vinyl chloride resin composition, and then obtain a compression set (JISK6301) and a JISA type hardness (JISK6301) of the obtained press plate. ) Was measured. Table 1 shows the results
Shown in

(Comparative Example 2) All of Example 2 was repeated except that 23.4 g of hexamethylene diisocyanate (NCO / OH ratio: 1) was used in place of the trimer of hexamethylene diisocyanate (Coronate EH) in Example 2. It was similarly manufactured and evaluated. The THF-insoluble content was measured using the Soxhlet extraction method. Table 1 shows the results.

[Effect of the Invention] As is clear from the above description, the vinyl chloride resin composite having rubber elasticity obtained by the present invention is rich in flexibility and easy in moldability. It is further characterized by high rebound resilience and low compression set.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) C08L 27/06 C08L 75/04 C08L 9/02

Claims (1)

(57) [Claims] 1. A composition comprising a vinyl chloride resin, a polymer polyol having two or more hydroxyl groups and a molecular weight of 300 to 10,000 and a compound having three or more isocyanate groups, which are heated and melted under shearing force. Vinyl chloride resin composition 10 having a tetrahydrofuran insoluble content of 5 to 55% by weight
A crosslinked acrylonitrile-butadiene copolymer having an amount of bound acrylonitrile of 25 to 50% by weight and a tetrahydrofuran insoluble content of 60 to 95% by weight based on 0 part by weight is used.
A vinyl chloride resin composition, wherein the composition comprising 10 parts by weight or more and 200 parts by weight or less has a tetrahydrofuran insoluble content of 10 to 80% by weight.