JPH04220416A - Vinyl chloride resin composition - Google Patents

Abstract

PURPOSE:To provide a vinyl chloride resin compsn. suitable for the use requiring rubber elasticity. CONSTITUTION:A vinyl chloride resin compsn. which is prepd. by melt mixing a vinyl chloride resin impregnated with a plasticizer, a polymer polyol having at least two hydroxyl groups and a mol.wt. of 300-10,000, and a compd. having at least three isocyanate groups under a shearing force and has a tetrahydrofuran-insol. content of 5-60wt.%.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vinyl chloride resin composition suitable for uses requiring rubber elasticity.

0002

BACKGROUND OF THE INVENTION Conventionally, methods for improving the rubber elasticity of vinyl chloride resins include organic peroxides such as benzoyl peroxide, dicumyl peroxide, and t-butyl peroxide, such as 1,4-tetramethylene diamine. , crosslinking of vinyl chloride resin with diamine compounds such as 1,6-hexamethylene diamine, sulfur, tetramethylthuram disulfide, triazine dithiol, etc., components such as diallylphthalate, crosslinkable polyurethane, or epoxy resin. A method of crosslinking, a method of blending a crosslinked vinyl chloride resin that has been crosslinked in advance during polymerization, a crosslinked NBR that is highly compatible with the vinyl chloride resin, a crosslinked polyurethane, etc. with the vinyl chloride resin, a method that uses vinyl chloride that has a reactive group such as a hydroxyl group. There is a method of crosslinking a resin with diisocyanate or the like.

[0003] In these methods, when crosslinking vinyl chloride resin, it is possible to easily obtain a rubber-like elastic body, but on the other hand, there are problems: (1) poor thermal stability and easy discoloration; (2) An odor remains due to the residue of the crosslinking agent. (3) If the degree of crosslinking is increased, there are problems such as the need for a large amount of plasticizer to achieve a desired hardness.

[0004] When a reactive plasticizer is used, the same problem as mentioned above occurs because it is often a radical reaction system.

When blending cross-linked vinyl chloride resin or cross-linked NBR with vinyl chloride resin, (1) physical properties such as tensile strength and elongation are significantly reduced due to their dispersibility in the vinyl chloride resin ( 2) A large amount of plasticizer is required to adjust the hardness (3) Decrease in impact resilience (4) Addition of a large amount will worsen moldability (5) If used for a long time at high temperatures or in a place exposed to sunlight, it will deteriorate. There are problems such as not being able to maintain the initial performance.

Furthermore, in the method of crosslinking a vinyl chloride resin having a reactive group such as a hydroxyl group with diisocyanate or the like, it is difficult to obtain the desired elasticity due to poor reactivity.

[0007] In recent years, the composite of vinyl chloride resin and polyurethane has attracted attention, and various methods have been proposed. For example, a method in which polyurethane is dissolved in vinyl chloride monomer (VCM) and a composite of vinyl chloride resin and polyurethane is obtained by polymerizing VCM, and a hydroxyl group-containing vinyl chloride resin is produced by polymerizing VCM in the presence of a polyol. There is a method of obtaining it by a urethanization reaction, and a method of obtaining it by impregnating a vinyl chloride resin with a polyol, an isocyanate, a catalyst, etc. and reacting the same.

However, the composites of vinyl chloride resin and polyurethane obtained by these methods have poor rubber elasticity and are not suitable for applications requiring rubber elasticity. In a method for producing such a composite, if a crosslinked urethane is produced using triisocyanate, the processability will be poor.

[0009] Furthermore, as a commonly used composite method of vinyl chloride resin and polyurethane, there is a method of polymer blending vinyl chloride resin and polyurethane elastomer having high elasticity in a roll or Banbury mixer.

Although the composite obtained by this method has excellent impact resilience, it has poor compression set, and therefore improvements are desired.

[0011] As a result of recent studies, we have found that a method to solve these problems is to use vinyl chloride resin, a polymer polyol having two or more hydroxyl groups and a molecular weight of 300 to 10,000, and an isocyanate group. A vinyl chloride resin composition obtained by heat-melting and mixing compounds having three or more of these under shearing force, the vinyl chloride resin composition having a tetrahydrofuran (THF) insoluble content of 5 to 55% by weight. suggested something.

0012

[Problems to be Solved by the Invention] This composition solved the problems of conventional vinyl chloride elastomers and provided sufficient rubber elasticity, but in order to provide rubber elasticity equivalent to that of crosslinked rubber, Furthermore, it is necessary to produce a higher degree of urethane crosslinking.

However, if the THF-insoluble content is increased in order to produce a highly crosslinked urethane, the composition will not be plasticized.

On the other hand, even with the above-mentioned composition having the THF-insoluble content, the surface smoothness of the molded product may be poor.

[0015]

[Means for Solving the Problems] In view of the above-mentioned current situation, the present inventors have investigated a vinyl chloride resin composition that has excellent gelling and melting properties when producing a more advanced cross-linked urethane product. , we have completed the present invention.

That is, the present invention provides vinyl chloride resin 10
A vinyl chloride resin composition obtained by adding 5 to 100 parts by weight of a plasticizer to 0 parts by weight and drying it, a polymer polyol having two or more hydroxyl groups and a molecular weight of 300 to 10,000, and an isocyanate group. A vinyl chloride resin composition obtained by heating and melting mixing a compound having three or more of these under shearing force, the vinyl chloride resin having a tetrahydrofuran (THF) insoluble content of 5 to 60% by weight. The present invention relates to a composition.

The present invention will be explained in detail below. The vinyl chloride resin used in the present invention may be obtained by a commonly used polymerization method. Examples include suspension polymerization, bulk polymerization, solution polymerization, and emulsion polymerization.

[0018] The vinyl chloride resin referred to in the present invention is
Refers to vinyl chloride homopolymers and copolymerized vinyl chloride resins with monomers copolymerizable with vinyl chloride monomers. Also,
The degree of polymerization of the vinyl chloride resin used is in the range of 800 to 8,000, preferably 1,000 to 5,000.

Monomers copolymerizable with the vinyl chloride monomer include, for example, ethylene, propylene, butene, pentene-1, butadiene, styrene, α-methylstyrene, acrylonitrile, vinylidene chloride, vinylidene cyanide, alkyl Examples include vinyl ethers, carboxylic acid vinyl esters, aryl ethers, dialkylmaleic acids, fumaric esters, N-vinylpyrrolidone, vinylpyridine, vinylsilanes, acrylic acid alkyl esters, methacrylic acid alkyl esters, etc. .

Furthermore, the vinyl chloride resin may be a graft polymer such as an ethylene-vinyl acetate-vinyl chloride graft polymer or a vinyl chloride-urethane copolymer. However, the vinyl chloride resin is not limited to these. Also used are crosslinked vinyl chloride resins obtained by adding a divinyl compound such as divinylbenzene during polymerization of these polymers.

The crosslinked vinyl chloride resin has a tetrahydrofuran (THF) insoluble content in the range of 0.1 to 25% by weight, and is used alone or in a blend with an uncrosslinked vinyl chloride resin.

The plasticizer used in the present invention may be one that is normally added to vinyl chloride resin, and is not particularly limited. Examples of such plasticizers include di-n-butyl phthalate, di-2-ethylhexyl phthalate (DOP), di-n-octyl phthalate, diisooctyl phthalate, octyldecyl phthalate, diisodecyl phthalate, Phthalic acid plasticizers such as butyl benzyl phthalate and di-2-ethylhexyl isophthalate, di-2-ethylhexyl adipate (DOA), di-n-decyl adipate, diisodecyl adipate, dibutyl sebacate, and di-sebacate. -2- Aliphatic ester plasticizers such as ethylhexyl, trimellitic acid plasticizers such as trioctyl trimellitate and tridecyl trimellitate, pyromellitic acid plasticizers such as tetraoctyl pyromellitate, tributyl phosphate, phosphorus Tri-2-ethylhexyl acid, phosphoric acid 2
- Average molecular weight obtained by condensation polymerization of phosphate ester plasticizers such as ethylhexyl diphenyl and tricresyl phosphate, epoxy plasticizers such as epoxidized soybean oil and epoxidized linseed oil, adipic acid or sebacic acid, and glycol 500 ~10,000 polymer plasticizers, etc., and one or more of these may be used.

In the present invention, a plasticizer is added to the vinyl chloride resin in advance and then dried up, and the amount of plasticizer at this time is 5 to 100 parts by weight. If it is less than 5 parts by weight, the gelling and melting properties of the vinyl chloride resin will not be improved, and if it exceeds 100 parts by weight, the miscibility with the urethane component to be mixed later will deteriorate, which is not preferable.

[0024] The polymer polyol used in the present invention is:
Contains 2 or more hydroxyl groups and has a molecular weight of 300 or more and 10,0
00 or less, preferably 1,000 or more 5,000
These are as follows. Such polymer polyols have, for example, 4 to 10 carbon atoms.
It can be obtained by condensation polymerization of an aliphatic dicarboxylic acid with a glycol having 5 or less repeating units obtained by ring-opening polymerization of an aliphatic glycol having 2 to 10 carbon atoms and/or an epoxy group.

The term "molecular weight" used in the present invention refers to the number average molecular weight, which can be measured by gel permeation chromatography (GPC) or the like.

The aliphatic glycol having 2 to 10 carbon atoms used in the production of polymer polyols is, for example, 1,
2-ethanediol, 1,2-propanediol, 1,
4-butanediol, butenediol, 3-methyl-1
, 5-pentanediol, 1,6-hexanediol, 1,10-decamethylenediol, 2,5-dimethyl-2.5-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol and the like.

On the other hand, as a compound having an epoxy group,
Examples include cyclic ethers such as ethylene oxide, propylene oxide, and tetrahydrofuran (THF). Glycols having 5 or less repeating units obtained by ring-opening polymerization of these are also suitably used as the glycol of the present invention. One or more of these may be used.

Examples of aliphatic dicarboxylic acids having 4 to 10 carbon atoms used in the production of polymer polyols include succinic acid, glutaric acid, adipic acid, azelaic acid,
Examples include sebacic acid, and one or more of these may be used.

[0029] Such polymer polyols include:
It is commercially available from Nippon Polyurethane Co., Ltd. under the trade name Nipporan.

The amount of the polymer polyol added is preferably 10 to 180 parts by weight per 100 parts by weight of the vinyl chloride resin. If it is less than 10 parts by weight, the rubber elasticity will not be improved.
If it exceeds 0 parts by weight, processing becomes impossible.

Compounds having three or more isocyanate groups used in the present invention include, for example, 2,4- and 2,6-
Tolylene diisocyanate, m- and p-phenylene diisocyanate, 1-chlorophenylene-2,4-
Diisocyanate, 1,5-naphthalene diisocyanate, methylenebisphenylene-4,4'-diisocyanate, m- and p-xylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate,
Trimers of diisocyanates such as 4,4'-methylenebiscyclohexyl diisocyanate, isophorone diisocyanate, trimethylhexamethylene diisocyanate, 1,6,11-undecane triisocyanate,
Examples include triisocyanates such as lysine ester triisocyanate and 4-isocyanate methyl-1,8-octamethyl diisocyanate, or polyfunctional isocyanates such as polyphenylmethane polyisocyanate, and one or more of these may be used. be done. It is also possible to use the above diisocyanates in combination.

However, the number of moles of NCO groups in the triisocyanate relative to the number of moles of NCO groups in all isocyanates is 0.
25 or more is desirable. If it is less than 0.25, sufficient performance cannot be exhibited due to insufficient crosslinking density.

[0033] Also, the NCO/OH ratio is 0.3 to 1.3.
A range of is preferred. If it is less than 0.3, even if only triisocyanate is used as the isocyanate, sufficient performance cannot be exhibited due to insufficient crosslinking density. If it exceeds 1.3, processing cannot be performed.

In the present invention, methyl methacrylate-
Alkyl acrylate copolymers can also be used as gelation and meltability improvers for vinyl chloride resins. As the methyl methacrylate-alkyl acrylate copolymer,
It may be obtained by general emulsion polymerization, for example, by methods such as those exemplified in JP-A-57-109812 and JP-A-57-74347. The component ratio of the copolymer is 50 to 95% by weight of methyl methacrylate and 5 to 50% by weight of alkyl acrylate, and the molecular weight of the obtained copolymer is, for example, 0.1 g of this copolymer mixed with 100 cc of chloroform. It is evaluated by the reduced viscosity of the solution at 25°C when dissolved. Generally, the smaller the value, the lower the molecular weight, and the better the dispersibility in vinyl chloride resin. Conversely, the larger this value is, the higher the molecular weight, and the more difficult the molecular chain is. It is said that entanglement leads to imparting rubber elasticity. The optimum reduced viscosity value of the methyl methacrylate-alkyl acrylate copolymer used in the present invention is 1-10.

The alkyl acrylate preferably has an alkyl group having 1 to 10 carbon atoms, such as methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, etc. It is not limited to. Also, one or more of these may be copolymerized with methyl methacrylate.

The amount of the methyl methacrylate-alkyl acrylate copolymer thus obtained is preferably 0.1 to 30 parts by weight per 100 parts by weight of the vinyl chloride resin. If it is less than 0.1 part by weight, the gelling and melting properties of the vinyl chloride resin will not be improved, and if it exceeds 30 parts by weight, the low price, which is one of the characteristics of vinyl chloride resin, will be lost, which is not preferable.

In particular, when a high degree of rubber elasticity is required and the vinyl chloride resin used has a high degree of polymerization, or when the weight fraction of urethane crosslinking in the composition is high, the addition of this resin is
is important.

Catalysts may be used in preparing the compositions of this invention. Although the reaction proceeds without using a catalyst, it is preferable to use a catalyst because the reaction proceeds more uniformly. Such a catalyst may be any catalyst used in general urethanization reactions, such as amine catalysts such as triethylamine, triethylenediamine, and N-methylmorpholine, tetramethyltin, tetraoctyltin, and dimethyldioctyltin. , triethyltin chloride, dibutyltin diacetate, dibutyltin dilaurate, and other tin-based catalysts.

In the present invention, a stabilizer can also be added to the vinyl chloride resin. Examples of stabilizers include metal soap stabilizers such as lead stearate, calcium stearate, barium stearate, zinc stearate, and cadmium stearate, and epoxy stabilizers such as epoxidized soybean oil and epoxidized linseed oil. Can be mentioned.

Further, if necessary, commonly used ultraviolet absorbers, antioxidants, anti-aging agents, processing aids, fillers, etc. can be added. However, in the present invention,
If a tin-based stabilizer is used, it becomes a hydrolysis catalyst for the ester-based polymer polyol, so it is better to avoid using it.

The composition of the present invention is prepared in a kneading machine capable of shearing and melting resin, such as a roll molding machine, a twin-screw kneading machine, an extruder, or a Banbury mixer. The plasticizer-impregnated vinyl chloride resin is prepared using a mixer capable of drying up, such as a Henschel mixer, a ribbon blender, or a super mixer.

More specifically, first, as a method for preparing a plasticizer-impregnated vinyl chloride resin, for example, in a Henschel mixer, vinyl chloride resin and, if necessary, commonly used heat stabilizers, ultraviolet absorbers, antioxidants, aging Add the inhibitor, processing aid, filler, etc., and add the plasticizer to this while heating and stirring. Then, heating and stirring are continued until the resin temperature reaches 120° C. to prepare a plasticizer-impregnated vinyl chloride resin.

Next, in order to produce the composition of the present invention, for example, using a Banbury mixer, the previously prepared plasticizer-impregnated vinyl chloride resin is first added at a casing temperature of 100 to 200°C. Mix. Next, the polyol, isocyanate, catalyst, and, if necessary, a plasticizer, which have been kept at a temperature of 50 to 80° C., are weighed and mixed, and the mixture is charged through the input port of a Banbury mixer. While applying a shearing force, the temperature is set to 100 to 200°C, and heating and mixing are continued to perform melting and urethanization reaction of the vinyl chloride resin, and after 3 to 60 minutes, it is taken out. The resin composition thus obtained can be formed into a sheet by applying it to a roll molding machine.

The THF-insoluble content of the composition of the present invention is 5 to 6.
It is necessary that it be 0% by weight. When the insoluble content is less than 5% by weight, sufficient compression set cannot be imparted, and when it exceeds 60% by weight, molding becomes difficult.

The method for measuring this THF-insoluble content is as follows. That is, a roll sheet with a thickness of 1.0 ± 0.1 mm is cut into 1.0 to 1.5 mm squares, and 1.0 g
Weigh. Put this in a 300cc beaker and add 200
Stir with a stirrer in mlTHF for 2 hours. The sample, which swells with THF, is filtered through a 300-mesh sieve, crushed with a glass rod, etc., and the filtrate is further stirred in 200 ml of THF with a stirrer for 4 hours. This solution was passed through a pre-weighed filter paper to separate the insoluble matter, and the insoluble matter and the filter paper were placed in a Petri dish at 40°C.
After drying in an oven for 5 hours, the weight is measured. The weight percent of the THF insoluble matter is determined from the weight of the insoluble matter obtained by this method.

[0046]

EXAMPLES The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited thereto.

Reference Example 1 Methyl methacrylate and n-butyl acrylate were copolymerized according to the method exemplified in JP-A-57-74347. At this time, the composition ratio of the copolymer was 90% methyl methacrylate and 10% n-butyl acrylate, and 0.1 g of the obtained copolymer was mixed with 100 cc of chloroform.
The reduced viscosity of the solution at 25℃ when dissolved in is 3.3
Met.

Reference Example 2 In the same manner as in Reference Example 1, the amount of chain transfer agent was reduced.
Copolymerization of methyl methacrylate and n-butyl acrylate was carried out. The composition ratio of the copolymer at this time was 90% methyl methacrylate and 10% n-butyl acrylate, and the composition ratio of the obtained copolymer 0.1g dissolved in 100cc chloroform at 25°C. The reduced viscosity was 7.6.

Reference Example 3 In a Henschel mixer, a vinyl chloride resin obtained by suspension polymerization (manufactured by Tosoh Corporation, trade name: Ryuron E-2) was placed in a Henschel mixer.
800, average degree of polymerization 2800) as stabilizers, barium stearate 28 g, zinc stearate 14 g, amine scavenger 21 g of Nissan Ferro Organic Chemical Co., Ltd., trade name BP-331, and dibutyl phthalate. (DBP) 700g was charged and continued heating and stirring. Then, by completing dry-up at 120°C, a plasticizer-impregnated vinyl chloride resin was prepared.

Reference Example 4 In a Henschel mixer, 1 kg of a vinyl chloride resin with an average degree of polymerization of 4,200 obtained by a normal suspension polymerization method, 20 g of barium stearate as a stabilizer, 10 g of zinc stearate, and as an amine scavenger were added. Nissan Ferro Organic Chemistry (
15 g of BP-331 (trade name) manufactured by Co., Ltd. and 1 kg of dibutyl phthalate (DBP) were added, and the mixture was heated and stirred. Then, by completing dry-up at 120°C, a plasticizer-impregnated vinyl chloride resin was prepared.

Example 1 618 g of the plasticizer-impregnated vinyl chloride resin prepared in Reference Example 3 was charged into a Banbury mixer with an internal volume of 1700 cc and a casing temperature of 150° C. and stirred at a constant rotation speed. Separately, 720 g of polymer polyol (manufactured by Nippon Polyurethane Co., Ltd., trade name Nipporan 4067, number average molecular weight 2,000) was kept at 70°C in advance.
and a trimer of hexamethylene diisocyanate (manufactured by Nippon Polyurethane Co., Ltd., trade name Coronate HX) 1
21 g (NCO/OH ratio = 1) of dibutyltin dilaurate 0.07 g was charged as a catalyst, mixed for 1 minute, and then poured into the Banbury mixer inlet. The reaction and mixing time was then 15 minutes.

[0052] After the reaction was completed, the obtained composite was put into a sheet using a roll forming machine, and then press-molded to a thickness of 12.70±0.13 mm in accordance with JIS K 6301 compression set. Subsequently, the compression set (JIS K 6301) and JIS A type hardness (JIS K 6301) of the obtained press plate were measured. Furthermore, THF
The weight percent of insoluble matter was measured.

[0053] Separately, a sheet-like product was formed by extrusion molding of this product, and the surface smoothness of the appearance of the product was visually observed and evaluated as follows. ○: Excellent ×: The surface is rough and uneven, and the results are not glossy.Table 1
Shown below.

Example 2 A product was produced and evaluated in the same manner as in Example 1, except that 8 g of the copolymer of methyl methacrylate and n-butyl acrylate produced in Reference Example 1 was added. . The results are shown in Table 1.

Example 3 A product was produced and evaluated in the same manner as in Example 1, except that 8 g of the copolymer of methyl acrylate and n-butyl acrylate produced in Reference Example 2 was added. . The results are shown in Table 1.

Example 4 1022.5 g of the plasticizer-impregnated vinyl chloride resin prepared in Reference Example 4 was charged into the Banbury mixer used in Example 1 and stirred at a constant rotational speed. Also, apart from this, the temperature is 70℃ in advance.
400 g of a polymer polyol (manufactured by Nippon Polyurethane Co., Ltd., trade name Nipporan 4067, number average molecular weight 2,000) kept at a temperature of HX) 67.2g (NCO/OH ratio = 1
) 0.04 g of dibutyltin diurarate was added as a catalyst, mixed for 1 minute, and then poured into the Banbury mixer inlet. Manufacturing and evaluation were performed in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1 In the Banbury mixer used in Example 1, 40% of vinyl chloride resin (manufactured by Tosoh Corporation, trade name: Lyuron E-2800, average degree of polymerization 2800) obtained by suspension polymerization was added.
0 g of barium stearate and 4 g of zinc stearate as stabilizers, and 6 g of BP-331 (trade name, manufactured by Nissan Ferro Organic Chemical Co., Ltd.) as an amine scavenger, and were stirred at a constant rotational speed. Separately, 720 g of polymer polyol (manufactured by Nippon Polyurethane Co., Ltd., trade name Nipporan 4067, number average molecular weight 2,000) was kept at 70°C in advance.
and 200 g of dibutyl phthalate (DBP) were mixed, and hexamethylene diisocyanate trimer (manufactured by Nippon Polyurethane Co., Ltd., trade name Coronate HX) 121 was added to the mixture.
(NCO/OH ratio = 1) 0.07 g of dibutyltin dilaurate was charged as a catalyst, mixed for 1 minute, and then poured into the Banbury mixer inlet. Production was carried out in the same manner as in Example 1, but the composition taken out from the Banbury mixer after the reaction was not kneaded and was a material that was difficult to mold.

Comparative Example 2 500 g of vinyl chloride resin with an average degree of polymerization of 4,200 obtained by a normal suspension polymerization method in the Banbury mixer used in Example 1, 10 g of barium stearate, and zinc stearate as stabilizers. 5g, as an amine scavenger manufactured by Nissan Ferro Organic Chemical Co., Ltd., trade name BP-331, 7
．． Prepare 5g and 1kg of dibutyl phthalate (DBP)
was added and stirred at a constant rotational speed. Separately, 400 g of polymer polyol (manufactured by Nippon Polyurethane Co., Ltd., trade name Nipporan 4067, number average molecular weight 2,000), which had been kept at 70°C in advance, and 500 g of dibutyl phthalate (DBP) were mixed, To this was added 67.2 g of hexamethylene diisocyanate trimer (manufactured by Nippon Polyurethane Co., Ltd., trade name Coronate HX) (NCO/OH ratio = 1) and 0.04 g of dibutyltin diurarate as a catalyst, and after mixing for 1 minute, Banbury Pour it into the mixer inlet. Production and evaluation were performed in the same manner as in Example 1. The results are shown in Table 1.

[0059]

[Table 1]

[0060]

As is clear from the above description, the vinyl chloride resin composite having rubber elasticity obtained by the present invention has excellent surface smoothness and easy moldability. Furthermore, it is characterized by high impact resilience and low compression set.

Claims (1)

[Claims] 1. A vinyl chloride resin composition obtained by adding 5 to 100 parts by weight of a plasticizer to 100 parts by weight of a vinyl chloride resin and drying it, having two or more hydroxyl groups and a molecular weight of 300 or more.10. 000 or less and a compound having 3 or more isocyanate groups under shearing force.
60% by weight of a vinyl chloride resin composition.