JP3257153B2 - Method for producing polyvinyl chloride-polyurethane elastomer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a composite resin composition comprising polyurethane, polyvinyl chloride and carbon.

[0002]

2. Description of the Related Art Conventionally, as a method for improving the load-bearing deformation resistance of a polyvinyl chloride resin, that is, the compression set, benzoyl peroxide, dicumyl peroxide, t
-Sulfurization with organic peroxides such as -butyl peroxide, diamine compounds such as 1,4-tetramethylenediamine and 1,6-hexamethylenediamine, and sulfur compounds such as sulfur, tetramethylturum disulfide and triazinedithiol. Cross-linking of vinyl resin, component cross-linking such as diallyl phthalate, cross-linkable polyurethane or epoxy resin, or cross-linking vinyl chloride resin cross-linked in advance during polymerization or cross-linked NBR or cross-linked polyurethane with good compatibility with vinyl chloride resin There are a method of blending with a resin, a method of using a vinyl chloride resin having a reactive group such as a hydroxyl group to form a crosslinked body with diisocyanate or the like.

In these methods, when a vinyl chloride resin is crosslinked, a composition having good compression set can be easily obtained, but on the other hand, (1) poor thermal stability and coloring (2) The odor remains due to the residue of the cross-linking agent, and (3) If the degree of cross-linking is increased, a large amount of plasticizer is required to obtain a predetermined hardness.

When a reactive plasticizer is used, it is often a radical reaction system, so that the same problem as described above occurs.

[0005] When a crosslinked vinyl chloride resin or a crosslinked NBR is blended with a vinyl chloride resin, (1) physical properties such as tensile strength and elongation are remarkably reduced due to their dispersibility in the vinyl chloride resin. 2) A large amount of plasticizer is required for adjusting the hardness, (3) Moldability is deteriorated when a large amount is added, (4) Weather resistance and heat aging resistance are poor due to butadiene component in crosslinked NBR. There is.

Further, in the method of using a vinyl chloride resin having a reactive group such as a hydroxyl group to form a crosslinked product with diisocyanate or the like, the reactivity is poor, so that the improvement effect is small.

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 in which a polyurethane is dissolved in a vinyl chloride monomer (VCM) to obtain a composite of a vinyl chloride resin and a polyurethane by polymerization of the VCM, a method of producing a hydroxyl group-containing vinyl chloride resin by polymerization of the VCM in the presence of a polyol, And a method obtained by impregnating a vinyl chloride resin with a polyol, an isocyanate, a catalyst and the like, and reacting.

However, the composite of the polyvinyl chloride resin and the polyurethane obtained by these methods is inferior in rubber elasticity,
It is not suitable for applications requiring these properties. Further, when a urethane crosslinked product is produced using triisocyanate in such a method for producing a composite, the processability becomes poor.

Further, as a generally used method of combining a vinyl chloride resin and polyurethane, there is 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. Since the composite obtained by this method is inferior in compression set, improvement is desired. On the other hand, demands for rubber-like properties such as large injection molding, easy molding processability required for precision injection molding and the like, particularly decrease in melt viscosity, and further, compression set and creep resistance are increasing in recent years.
Materials that have low compression set and low melt viscosity are desired.

Under these circumstances, a method has recently been proposed in which a vinyl chloride resin, a polyol, an isocyanate compound, and, if necessary, a plasticizer are heated and melt-mixed under a shearing force to cause a urethane reaction to obtain a composite. I have. The composite obtained by this method is a material having low compression set and excellent moldability. However, if the carbon is added to the composite to provide further weather resistance, the carbon may be poorly dispersed, causing problems such as a decrease in tensile strength and a decrease in elongation.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a composite material comprising a polyvinyl chloride resin, polyurethane and carbon, which does not cause poor dispersion of carbon.

[0012]

Means for Solving the Problems In view of the above situation, the present inventors have made intensive studies on a method for producing a composite material, and as a result, have completed the present invention.

That is, the present invention relates to a method for producing a composite material comprising a polyvinyl chloride resin, a polyurethane comprising a polymer polyol and an isocyanate compound having three or more isocyanate groups, and a carbon composite material. This is a method for producing a polyvinyl chloride-polyurethane elastomer, wherein a urethane reaction is performed while heating and melting and mixing with a system resin under shearing force, and carbon is added after the completion of the urethane reaction. The details of the present invention are described below.

The polyvinyl chloride resin used in the present invention means at least one of a vinyl chloride homopolymer resin, a chlorinated vinyl chloride resin, and all monomers copolymerizable with a vinyl chloride monomer. A vinyl chloride copolymer resin obtained by random copolymerization or block copolymerization (eg, vinyl acetate-vinyl chloride copolymer, ethylene-vinyl chloride copolymer, etc.), which is a single product or a mixture of two or more of the above resins. .

The polyols used in the present invention include polyester polyols, polyether polyols, polycarbonate polyols, castor oil polyols, and polyols such as saponified EVA (ethylene-vinyl acetate copolymer). Species or two or more species are used. The number of functional groups of the polyol is not particularly limited as long as it is 2 or more.

The mixing amount of the polyol is as follows.
20 parts by weight or more and 900 parts by weight or less with respect to 00 parts by weight. If the amount is less than 20 parts by weight, the rubber elasticity is not improved. If the amount exceeds 900 parts by weight, processing may not be performed.

The isocyanate 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, 1-chlorophenylene-2,4-diisocyanate, 1,5-
Naphthalenediisocyanate, methylenebisphenylene 4,4'-diisoanate, m- and p-xylenediisoanate, hexamethylene diisocyanate, lysine diisocyanate, 4,4'-methylenebiscyclohexyl diisocyanate, isophorone diisocyanate,
Trimer of diisocyanate such as trimethylhexamethylene diisocyanate, 1,6,11-undecane triisocyanate, lysine ester triisocyanate,
Triisocyanates such as -isocyanatomethyl-1,8-octamethyldiisocyanate or polyfunctional isocyanates such as polyphenylmethane polyisocyanate, and one or more of these are used. It is also possible to use the above diisocyanates in combination. However, in this case, N
It is desirable that the molar number of NCO groups of the triisocyanate is 0.25 or more based on the molar number of CO groups. If it is less than 0.25, sufficient performance may not be exhibited due to insufficient crosslinking density. Also, the N of the isocyanate compound used
When a diol is used as the polyol, the molar ratio between the CO group and the polyol group is preferably in the range of 0.3 to 1.3. If it is less than 0.3, even if only triisocyanate is used as the isocyanate, sufficient performance may not be exhibited due to insufficient crosslinking density, and if it exceeds 1.3, processing may not be performed.

The carbon used in the present invention is not particularly limited, and may be any carbon black usually added to rubber. The addition amount of carbon is not particularly limited, but if it exceeds 500 parts by weight with respect to 100 parts by weight of the polyvinyl chloride resin, the moldability may be significantly deteriorated.

According to the present invention, the polymer polyol and the isocyanate compound are subjected to a urethane reaction with a polyvinyl chloride resin while being heated and melt-mixed under shearing force, and carbon is added after the completion of the urethane reaction. Thus, when carbon is added after the urethane reaction, the dispersion of carbon becomes good and a composite material having improved mechanical properties such as tensile strength can be obtained. The completion of the urethane reaction can be easily evaluated by, for example, measuring the IR (infrared spectrum) of the isocyanate group. In the IR measurement, the absorption of the isocyanate group is 2270.
appeared in the vicinity cm ^-1 ~2280cm ^-1, the absorption disappears to form a urethane reaction. In the present invention, the use of the plasticizer is not limited. Examples of the plasticizer that can be used in the present invention include di-n-phthalic acid.
Butyl, di-2-ethylhexyl phthalate (DOP),
Phthalic acid plasticizers such as di-n-octyl phthalate, diisodecyl phthalate, diisooctyl phthalate, octyldecyl phthalate, butylbenzyl phthalate, and di-2-ethylhexyl isophthalate; di-2-ethylhexyl adipate (DOA ), Aliphatic ester plasticizers such as di-n-decyl adipate, diisodecyl adipate, dibutyl sebacate, di-2-ethylhexyl sebacate, and pyromellitic acid such as trioctyl trimellitate and tridecyl trimellitate. Plasticizers, phosphate plasticizers such as tributyl phosphate, tri-2-ethylhexyl phosphate, 2-ethylhexyl diphenyl phosphate, tricresyl phosphate, etc .; epoxy plasticizers such as epoxy soybean oil; polyester polymer plastics Agents and the like. It can be added more appropriate.

Further, in the present invention, heat stabilizers represented by metal salts and hydrotalcite, stabilizers such as ultraviolet absorbers, matting agents represented by partially cross-linked PVC, and processing aids represented by acrylic resins. An agent, a hydrolysis inhibitor represented by carbodiimide, a flame retardant represented by zinc borate and antimony trioxide, and the like can be added as necessary.

The heat-melting and mixing under shearing force in the present invention can be carried out, for example, by using a generally used manufacturing machine such as a twin-screw extruder, a single-screw extruder, a kneader, a Banbury mixer, and a roll. .

[0022]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited to these examples.

Example 1 An ethylene-vinyl chloride copolymer (Rulon E-2800, Toso-Tokyo Co., Ltd.) obtained by a suspension polymerization method in a Banbury mixer having an internal volume of 1700 cc and a casing temperature of 150 ° C.
100 parts by weight, 2 parts of barium stearate as a stabilizer, 1 part of zinc stearate, 1.5 amine supplement (trade name: BP-331, manufactured by Nissan Ferro-Organic Chemical Co., Ltd.)
The part was charged and stirred at a constant rotation speed. Separately, a polymer polyol obtained by condensation polymerization of 1,4-butanediol, ethylene glycol and adipic acid (Nipporan 404, manufactured by Nippon Polyurethane Co., Ltd.)
2, 80 parts by weight of number average molecular weight 2000) and 100 parts by weight of DOP (di-2-ethylhexyl phthalate) are mixed,
13. Trimer of hexamethylene diisocyanate (trade name: Coronate HX, manufactured by Nippon Polyurethane Co., Ltd.)
4 parts by weight (NCO / OH ratio = 0.85) and 0.015 part of dibutyltin dilaurate as a catalyst were charged, mixed for 1 minute, and then poured from the above Banbury mixer inlet.

After 10 minutes, a sample was taken out
It was confirmed by R (infrared spectrum) that no isocyanate group remained, and 25 parts by weight of MAF carbon (manufactured by Mitsubishi Kasei Co., Ltd., trade name: Diablack M) was added as a carbon and kneaded for 10 minutes. A composite material was obtained.

Thereafter, the obtained composite material was applied to a roll forming machine to form a sheet, and then press-formed to a thickness of 1 mm for a JIS K6301 tensile test. Further, this pressed product was punched out into a dumbbell shape No. 3 as a sample, and evaluated.

Example 2 A composite material was obtained in the same manner as in Example 1 except that the amount of carbon was changed to 50 parts by weight, and this was evaluated.

Example 3 A composite material was obtained in the same manner as in Example 1 except that HAF carbon (manufactured by Mitsubishi Kasei Co., Ltd., Diablack H) was used instead of the MAF carbon, and a composite material was evaluated. did.

Comparative Example 1 A composite material was obtained in the same manner as in Example 1 except that no carbon was used, and evaluated.

Comparative Example 2 Polymer polyol, isocyanate compound, plasticizer,
Example 1 except that when adding the catalyst, carbon was added and mixed together, and then put into a Banbury mixer.
A composite material was obtained in the same manner as described above, and was evaluated.

Comparative Example 3 Polymer polyol, isocyanate compound, plasticizer,
Example 1 except that when adding the catalyst, carbon was added and mixed together, and then put into a Banbury mixer.
A composite material was obtained in the same manner as described above, and was evaluated.

Comparative Example 4 Polymer polyol, isocyanate compound, plasticizer,
Example 1 except that when adding the catalyst, carbon was added and mixed together, and then put into a Banbury mixer.
A composite material was obtained in the same manner as described above, and was evaluated.

Comparative Example 5 A composite material was obtained in the same manner as in Example 1 except that carbon was added and mixed together with a polyvinyl chloride resin and a stabilizer, and the mixture was put into a Banbury mixer.

(Evaluation of tensile properties) Measured according to JIS K6301. Table 1 shows the results.

[0034]

[Table 1]

[0035]

As described above, according to the method of the present invention, it is possible to obtain a vinyl chloride-polyurethane composite material having a good carbon dispersion, and this composite material composite has a thermal property excellent in tensile properties. It becomes a plastic elastomer.

Claims (1)

(57) [Claims] 1. A method for producing a composite material comprising a polyvinyl chloride resin, a polyurethane comprising a polymer polyol and an isocyanate compound having three or more isocyanate groups, and a carbon composite material, wherein the polymer polyol and the isocyanate compound are combined with the polyvinyl chloride resin. A method for producing a polyvinyl chloride-polyurethane elastomer, comprising reacting a urethane while heating and mixing under a shearing force, and adding carbon after completion of the urethane reaction.