JPH0431453A - Vinyl chloride resin composition - Google Patents

Abstract

PURPOSE:To obtain a vinyl chloride resin composition improved in migration resistance, transparency and flexibility by mixing a vinyl chloride resin with a plasticizer comprising a specified compound. CONSTITUTION:A polyester alcohol of formula I (wherein R<1> is 1-20 C alkyl or aralkyl; R<2> is an aliphatic hydrocarbon group; and n is 2-200) is reacted with a polyisocyanate at 0-150 deg.C for 30 min to 50hr to obtain an NCO-terminated urethane polymer. This urethane prepolymer is reacted with trimethylolpropane in a molar ratio of 1-3 to obtain a plasticizer comprising a urethane compound having a polyester skeleton of formula II (wherein R<3> is a bivalent hydrocarbon group; and x is 1-3). 100 pts.wt. vinyl chloride resin is mixed with 5-400 pts.wt. said vlasticizer and optionally another thermoplastic resin, a rubber, a stabilizer, a lubricant, a filler, a flame retardant, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a vinyl chloride resin composition containing a urethane compound having a polyester skeleton as a plasticizer.

[Conventional technology]

Vinyl chloride resin can have its physical properties changed over a very wide range by adding a plasticizer, and is widely used industrially as a thermoplastic resin suitable for various uses. As plasticizers for vinyl chloride resins, phthalate esters such as dioctyl phthalate and fatty acid esters such as dioctyl adipate are the most common because of their excellent plasticizing efficiency. However, these plasticizers have a tendency to migrate from the inside of the molded product to the surface, and molded products containing these plasticizers not only deteriorate in physical properties over time due to a decrease in plasticizer content, but also cause the molded product and other Prolonged contact with resin molded products causes the plasticizer to migrate to other resin molded products, causing alteration and deterioration of the resin molded products.

In order to prevent plasticizer migration, flexible polymeric compounds are used to plasticize vinyl chloride resins, such as ethylene-vinyl acetate copolymer, ethylene-carbon oxide-vinyl acetate copolymer, thermoplastic polyurethane, NBR, etc. Attempts have been made to blend PVC into vinyl chloride resin, but even with PVC resin plasticized with such a polymer compound, the transfer of the composition is slightly different from that of a liquid plasticizer. If another resin molded product comes into contact with a molded product made from the molded product, the surface of the other resin molded product will be contaminated with blooms from the molded product in a harsh environment of high temperature and humidity, and the liquid plasticizer may migrate. A similar phenomenon (hereinafter also referred to as "migration") occurs, and migration can be completely avoided.

Among these polymeric plasticizers, poly-ε-caprolactone has good hydrolysis resistance and relatively excellent non-migration properties in harsh environments of high temperature and humidity. However, poly-[epsilon]-caprolactone has strong crystallinity, which causes problems such as changes in hardness over time and, for example, loss of transparency, as disclosed in Japanese Patent Publication No. 60-90208.

[Problem to be solved by the invention]

The present invention relates to a vinyl chloride resin composition containing, as a plasticizer, a urethane compound having a polyester skeleton that has excellent non-migration properties, transparency, and flexibility.

[Means to solve the problem]

The present inventors conducted intensive studies to solve the above-mentioned problems, and as a result, the following general formula (I
) A vinyl chloride resin composition containing 5 to 400 parts by weight of the urethane compound represented by the following formula was discovered, and the present invention was achieved.

... (I) [In the formula, R' = alkyl group or aralkyl group having 1 to 2 carbon atoms R2: aliphatic hydrocarbon group R3: divalent hydrocarbon group n: 2 to 200 χ: 1 to 3] The present invention will be explained in detail below.

As the vinyl chloride resin used in the composition of the present invention, vinyl chloride or a mixture of vinyl chloride and a comonomer copolymerizable therewith can be prepared by a suspension polymerization method, a bulk polymerization method, a fine suspension polymerization method, or an emulsion polymerization method. All products manufactured by this method can be used.

Therefore, examples of comonomers that can be copolymerized with vinyl chloride include vinyl esters such as vinyl acetate, vinyl propionate, and vinyl laurate; methyl acrylate;
Acrylic acid esters such as ethyl acrylate and butyl acrylate, methacrylic acid esters such as methyl methacrylate and ethyl methacrylate, maleic acid esters such as dibutyl maleate and diethyl maleate, fulleric acid esters such as dibutyl fumarate and diethyl fumarate. vinyl ethers such as vinyl methyl ether, vinyl butyl ether, vinyl octyl ether,
These comonomers include vinyl cyanides such as acrylonitrile and methacrylate, α-olefins such as ethylene, propylene, and styrene, and vinyl halides other than vinyl chloride such as vinylidene chloride and vinyl bromide. 30% by weight or less in the constituent components of the resin,
It is preferably used within a range of 20% or less.

Of course, the comonomers are not limited to those mentioned above.

rl) R' in A' is an alkyl group or an aralkyl group having 1 to 2 carbon atoms, preferably an alkyl group having 1 to 10 carbon atoms, specifically a methyl group, an ethyl group, n
-propyl group, j-propyl group, n-butyl group, 5ec
-butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, n-octyl group, 2-ethylhexyl group, nonyl group, decyl group and the like.

R2 is an aliphatic hydrocarbon group, preferably a branched or straight chain aliphatic hydrocarbon group having 3 to 8 carbon atoms. Specifically, it corresponds to an aliphatic hydrocarbon group of a polyester produced by ring-opening polymerization of a lactone compound, which will be described later, and is preferably CFI.

CHz CCHHz CHz- CHz CHz CHz CHt CHzHz
CH3 CHz CHCHg CHz- CH3 -CH, -C-CHArCHz- CH.

can be mentioned.

R3 is a divalent hydrocarbon group, preferably a divalent alkyl group, an aralkyl group, or an aryl group.

Urethane compound (1) having a polyester skeleton of the present invention
) are trimethylolpropane,
These are polyisocyanate and polyester alcohol represented by the following general formula (It).

R' 0-(-C-R2-0 masu--H... (II
) [In the formula, R' and R11n have the same meanings as the above general formula (I)] The polyisocyanate used here is a diisocyanate that is generally used as a raw material for polyurethane, such as hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4, 4′
-diisocyanates, 2.4.4-) aliphatic diisocyanates such as dimethylhexane-1,6-diisocyanate, tolylene-2,4-diisocyanate, tolylene-2,6-diisocyanate and mixtures thereof, diphenylmethane-4,4 '-diisocyanate, 3-methyldiphenylmethane-4,4-diisocyanate, m
and p-phenylene diisocyanate, naphthalene-1
, 5-diisocyanate, and a dihydric alcohol, and an excess of the above polyisocyanate (for example, tolylene-2,4-diisocyanate). etc.

As the polyisocyanate, it is also possible to use the above-mentioned polyisocyanates as a mixture of several kinds, and it is also possible to use the above-mentioned polyisocyanates dissolved in a solvent.

Preferred examples include tolylene-2,4-diisocyanate and isophorone diisocyanate (IPDI).

The above polyester alcohol (II) is usually produced through the following steps.

That is, a lactone compound represented by R'-0)l (R1 has the same meaning as the general formula (1) above) and an alcohol compound represented by the initiator is subjected to ring-opening polymerization to obtain the following.

Preferred initiators for R'O+C-R2-0-H R''-OH include n-butanol, n-hexanol, n-ophthal, 2-ethylhexanol, etc.Also, as the lactone compound, carbon number 3 to 8 lactones are preferred, including ε-caprolactone, β-methyl δ-valerolactone, β-ethyl-δ
- Valerolactone is particularly preferred.

This reaction is usually carried out in the presence of a catalyst. As a catalyst, known catalysts used for ring-opening polymerization of lactone, such as mineral acids such as sulfuric acid and phosphoric acid, alkali metals such as lithium, sodium, and potassium, alkyl metal compounds such as n-butyllithium, titanium tetrabutoxide, etc. Metal alkoxides and the like can be used.

Although this reaction can be carried out without a solvent, a solvent may be used depending on the case. As a solvent, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, chloroform, carbon tetrachloride, etc. can be used. The reaction conditions were from 1o to 3oC at a temperature between 0°C and 2°OoC.
This can be suitably carried out with a reaction time of 0 hours.

Here, the number n of repeating units can be controlled by the molar ratio of the starting side and the lactone compound, and is from 2 to about 2
It is about 00.

The urethane compound having a polyester skeleton of the present invention is usually produced by the following two steps. That is, in the first step, polyester alcohol (It) and polyisocyanate are reacted to obtain a urethane prepolymer having isocyanate groups at the ends.

This reaction is a urethane bond forming reaction, and these may be reacted in equimolar amounts. Although the reaction proceeds without a catalyst, a tin catalyst such as dibutyltin dilaurate, dibutyltin dioctoate, or dibutyltin mercaptide may be used to speed up the reaction rate.

A solvent may be used in these reactions. As the solvent, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, tetrahydrofuran, chloroform, carbon tetrachloride, etc. can be used. Reaction conditions are from 0°C to 150°
The reaction time is preferably 30 minutes to 50 hours.

Next, in the second step, the produced urethane prepolymer is reacted with trimethylpropane (hereinafter abbreviated as TMP).

This reaction is a urethane bond forming reaction, and the molar ratio of the urethane prepolymer to TMP is 1 to 3, preferably 3. Here, if the molar ratio is less than 1, unreacted TM
Since P remains, bleeding or crystallization occurs, making it impossible to achieve the object of the present invention, and if it is larger than 3, reactive isocyanate groups remain, which is undesirable as the stability of the plasticizer itself becomes poor. Although the reaction proceeds without a catalyst, a tin catalyst such as dibutyltin dilaurate, dibutyltin dioctoate, or dibutyltin mercaptide may be used to speed up the reaction rate.

However, the composition of vinyl chloride resin and polyester is
Usually, the former is 100 parts by weight and the latter is 5 to 400 parts by weight. If the latter is less than 5 parts by weight, the plasticizing effect will not be exhibited, while if it is more than 400 parts by weight, it will be difficult to maintain the shape of the vinyl chloride composition.

The composition of the present invention may contain additives normally used for vinyl chloride resins, such as other thermoplastic resins, rubbers, stabilizers, lubricants, fillers, and flame retardants.

Examples of other thermoplastic resins include ethylene-vinyl acetate copolymer, chlorinated polyethylene, ABS resin, AS resin, urethane, and acrylic resin. Examples of the rubber include NBR and CR.

Stabilizers include tribasic lead sulfate, dibasic lead phthalate, lead orthosilicate-silica gel coprecipitate, dibasic lead stearate, cadmium-barium stabilizer, barium-
Examples include zinc-based stabilizers, calcium-zinc-based stabilizers, tin-based stabilizers, and stabilizers containing metal salts such as magnesium, aluminum, and silicon as main components are also used.

As the lubricant, higher fatty acids or metal salts thereof, various paraffins, higher alcohols, natural waxes, polyethylene wax, fatty acid esters, fatty acid amides, etc. are used.

As the filler, calcium carbonate, clay, talc, silica-based fine powder, aluminum hydroxide, etc. are used.

Flame retardants include antimony trioxide, barium borate,
Zinc borate, zinc oxide, chlorinated polyethylene, and other halogen flame retardants are used.

In addition, the composition of the present invention may optionally contain antioxidants, ultraviolet absorbers, colorants, mold release agents, chelators, and crosslinking agents conventionally known for use in blending vinyl chloride resins. , a crosslinking aid may be added.

The above-mentioned essential components of the composition of the present invention and appropriately selected additives are uniformly dispersed and mixed using, for example, a ribbon blender, a high-speed mixer, etc. to form the composition of the present invention. This composition may be kneaded using a single-screw kneading extruder, twin-screw extruder, plasticator, co-kneader, panburi mixer, pressurized kneader-mill roll, etc., and formed into pellets to form a pellet-like composition. .

When used in paste processing, the vinyl chloride resin for the base and polyester are mixed using a ribbon blender, planetary mixer, Daysilver triple roll, etc. to form a paste, and then processed using the usual paste processing method. It can also be molded.

Furthermore, in order to use it for film formation from a solution, it is dissolved in a common solvent that dissolves polyester and vinyl chloride resin (for example, a mixed system such as THF may be used), and necessary additives are added.
A film can also be formed by forming a homogeneous solution and using a casting method.

[Effects of the Invention] Since the vinyl chloride resin composition of the present invention uses a urethane compound having a polyester skeleton as a plasticizer, it has excellent non-migration properties, transparency, and flexibility, and is extremely important industrially.

[Examples] Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited by the Examples unless the spirit thereof is exceeded.

Synthesis Example 1 After sufficiently purging a flask equipped with a stirring blade, a dropping funnel, and a gas inlet for polyester alcohol with dry nitrogen, 2-ethylhexanol 5
7 g and 1 g of metallic sodium were charged and stirred to dissolve the metallic sodium. Next, this flask was immersed in an oil bath at 40°C, and while stirring, 500 g of β-methyl-δ-valerolactone was added dropwise from the dropping funnel. After 1 hour, stirring was stopped and the contents of the flask were removed and dissolved in purified chloroform. This solution was poured into deionized water, washed, and the chloroform layer was separated.

After repeating this washing once more, the solvent was distilled off from the chloroform solution under reduced pressure to obtain a colorless and transparent polyester alcohol. The hydroxyl value of this product is 58.6 KOH
mg/g, and the acid value was 0.03 to 0)1 mg/g.

The flask is equipped with a stirring blade, a dropping funnel, and a gas inlet.
300 g of the above polyester alcohol and 54.6 g of 2,4-tolylene diisocyanate (TDI) were charged, the inside of the system was replaced with dry nitrogen, and then the system was sealed with nitrogen and reacted at 80° C. for 3 hours.

Next, 14.0 g of trimethylolpropane (TMP) was added dropwise from the dropping funnel while being heated and melted, and
The reaction was carried out at C for 5 hours. Isocyanate group (NCO group)
It was confirmed by IR that all of the components had reacted and disappeared. The viscosity of the obtained product was measured using an E-type rotational viscometer.2
The viscosity at 5°C was 90,000 cp. Also IR and N
The following structure was confirmed from the results of measuring the MR spectrum and the hydroxyl value of the polyester alcohol.

Synthesis Example 2 Synthesis Example 2 The same procedure as Synthesis Example 1 was carried out except that 22 g of 2-ethylhexanol was used. The obtained product had a hydroxyl value of 18.4.
KOHsg/g, acid value 0. IKOHmg/g.

300g of the above polyester alcohol, 2゜4-TD
Synthesis Example 1 was repeated except that 17.1 g of I1 and 13.1 g of STMP were used. It was confirmed by IR that all the NCO groups had reacted and disappeared. The product obtained is 2
The viscosity at 5°C was 175,000 cp. Furthermore, as a result of measuring IR and NMR spectra, it was confirmed that the product mainly consisted of the following structure.

口=Q 口=(Resynthesis Example 3 300 g of polyester alcohol synthesized in Yuritsukirijisai Synthesis Example 2,
The same procedure as in Synthesis Example 1 was carried out except that 17.1 g of 2.4-TDI and 4.4 g of TMP were used. It was confirmed by IR that all the NGO groups had reacted and disappeared. The resulting product had a viscosity of 317,000 cp at 25°C. Further, as a result of measuring IR and NMR spectra, it was confirmed that the structure was as follows.

Port=() Synthesis Example 4 300 g of the polyester alcohol of Synthesis Example 1, 69.7 g of isophorone diisocyanate, and 0.04 g of dibutyltin dilaurate were charged into a flask equipped with a plastic stirring blade, a dropping funnel, and a gas inlet. After replacing the inside of the system with dry nitrogen, the system was sealed with nitrogen and the reaction was carried out at 8°C for 6 hours.

Next, 14.0 g of TMP was added dropwise from the dropping funnel while being heated and melted, and the mixture was further reacted at 80° C. for 12 hours. NG
It was confirmed by IR that all O groups had reacted and disappeared. The resulting product had a viscosity of 116,000 cP at 25°C. Furthermore, as a result of measuring rR and NMR spectra, it was confirmed that the structure was as follows.

Mouth=ω Mouth=Q Examples 1 to 4, Comparative Example 1.2 100 parts by weight of suspension polymerized polyvinyl chloride (degree of polymerization 1300, homopolymer) and the plasticizer shown in Table 1 were mixed at about 15%.
It was dissolved in THF at a concentration of , to form a homogeneous solution. A film was formed from this solution by a casting method, and after being left overnight at room temperature,
Dry in an oven at 0°C for 7 hours to a thickness of approximately 100 μm.
created a film. This film was subjected to a tensile test, a migration test, a transparency test (haze measurement), and a hardness measurement using the methods described below. The results are summarized in Table 1.

1. Punch out a JISI dumbbell piece from a widely used film, set the chuck distance to 20ffII11, and pull at a pulling speed of 50 mm/min.
Tensilon tensile tester UTM-II [-100
A tensile test was conducted using

A plurality of layers of the long hill and fold film were stacked and pressed at 180°C to form a film having a thickness of about 1ffIII+. Sandwich this between polystyrene sheets and ABS sheets, apply a load of 300g, and
After being left in the oven for 7 days, the test piece was taken out and the presence or absence of plasticizer on the sheet surface was visually confirmed.

The haze was measured using an NDH-20D haze meter manufactured by Nippon Heavy Industries Ltd.

It was formed into a 2 ml thick sheet in the same manner as the countersunk transfer test piece, and six sheets were stacked to measure the hardness.

Claims (1)

[Claims] (1) A vinyl chloride resin composition containing 5 to 400 parts by weight of a compound represented by the following general formula (I) per 100 parts by weight of the vinyl chloride resin. ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(I) [In the formula, R^1: Alkyl group or aralkyl group having 1 to 20 carbon atoms R^2: Aliphatic hydrocarbon group R^3: Divalent Hydrocarbon group n: 2-200 x: 1-3]