JPS5938215A - Polyurethane-modified vinyl chloride polymer - Google Patents

Abstract

PURPOSE:To produce the titled flexible polymer excellent in hydrolysis resistance and low-temperature resistance, by dissolving a specified thermoplastic polyurethane in a vinyl chloride monomer and then radical-polymerizing the latter monomer. CONSTITUTION:The titled polymer is prepared by dissolving a vinyl chloride monomer-soluble thermoplastic polyurethane resin obtained by reacting a polyester-diol (preferably, one prepared by reacting an aliphatic diol with a dicarboxylic acid or its lower alkyl diester) with an aliphatic or alicyclic diisocyanate (e.g., hexamethylene diisocyanate or cyclohexylmethane diisocyanate) in a vinyl chloride monomer and then radical-polymerizing the latter monomer. This polymer is excellent in hydrolysis resistance, low-temperature resistance, weather resistance, flexibility, etc., and is useful in the production of a variety of molded products such as food utensils, medical appliances, packaging materials, hoses, belts, and sheets.

Description

Detailed Description of the Invention The present invention involves dissolving a special thermoplastic polyurethane resin that is soluble in vinyl chloride monomer obtained by reacting a polyester diol and an aliphatic diisocyanate, and then converting the vinyl chloride monomer into a radical. This invention relates to a polyurethane-modified vinyl chloride polymer obtained by polymerization.

Traditionally, vinyl chloride resin has been used in a wide range of fields due to its excellent solvent resistance, toughness, moldability, and low cost. ing. On the other hand, thermoplastic polyurethane is more expensive than general thermoplastic resins, so we use a method called polymer blending with polyvinyl chloride to mix and disperse the polymers and compensate for the physical properties of each. , automobile parts, industrial parts, etc. However, polymer blends must be mixed using mixing equipment such as extrusion, mixing rolls, Henschel mixers, Banbury mixers, etc., and it has not been possible to provide the expected inexpensive compounds. Furthermore, depending on the polyurethane glaze, the polymer blend itself may stick to the equipment, and the resulting compound may be so sticky that it cannot be supplied as a molding material. Furthermore, the resulting compound itself may not have satisfactory transparency or hardness due to insufficient dispersion, and may not be of practical use depending on the application.

The present inventors previously solved the above drawbacks at once in Japanese Patent Application No. 134050/1983 by dissolving a thermoplastic polyurethane soluble in a vinyl chloride monomer and then subjecting the vinyl chloride monomer to radical polymerization. However, as a result of intensive research, we found that by using a specific thermoplastic polyurethane obtained from polyester diol and aliphatic diisocyanate in the production of the above-mentioned polyurethane-modified vinyl chloride polymer, even better water resistance was achieved. It was discovered that a polyurethane-modified vinyl chloride polymer can be obtained that has degradability, cold resistance, weather resistance, and flexibility.
The present invention has now been completed. That is, the present invention provides a vinyl chloride monomer-soluble thermoplastic polyurethane 4 obtained by reacting a polyester diol with an aliphatic or alicyclic diisocyanate (I4 resin is dissolved in a vinyl chloride monomer,
Next, a polyurethane-modified vinyl chloride polymer is provided by radically polymerizing the vinyl chloride monomer solution.

The polyester diol of the present invention is preferably obtained from an aliphatic diol and a dicarboxylic acid or a lower alkyl diester thereof. The aliphatic diol is (a
) an aliphatic diol having no side chain having 4 to 12 carbon atoms and (
b) A mixed diol consisting of an aliphatic diol having a side chain of 3 to 12 carbon atoms is more preferable, and the proportion thereof is suitably mol% (al: (b) = 4 to 30 nia 0 to 96 The dicarboxylic acid or its lower alkyl diester is preferably an aliphatic dicarboxylic acid, particularly an aliphatic dicarboxylic acid having no side chain of 6 to 12 carbon atoms and a lower alkyl diester thereof. Examples of chainless aliphatic dicarboxylic acids and lower alkyl diesters thereof include adipic acid, azelaic acid, pimelic acid, sepacic acid, dodecanoic acid, and lower alkyl diesters of dimethyl, diethyl, and dibutyl thereof.

Examples of aliphatic diols having 4 to 12 carbon atoms without side chains include 1,4-butanediol, 1,6-hexanediol, 1,10-decamethylene glycol, etc. Examples of aliphatic diols having 6 to 12 side chains include 1,2-propylene glycol, 1°3-butylene glycol, 2,5-dimethyl-2,5-hexanediol, and 2,2-diethyl- 1
, 3-propanediol, neopentyl glycol, and the like.

Molecule ji of polyester diol used in the present invention:
is preferably 500 to 3,000, particularly preferably 1.000 to 2,500.

The aliphatic or cycloaliphatic diisocyanate of the present invention includes, for example, hexamethylene diisocyanate, lysine diisocyanate, cyclohexylmethane diisocyanate (water m
MD I ), 2.2.4- or 2,4.4-trimethylheximethylene diisocyanate, isopropylidene bis(4-cyclohexyl isocyanate), methylcyclohegan diisocyanate (hydrogenated TDI), isophorone diisocyanate, etc. .

In the present invention, aliphatic and cycloaliphatic diisocyanates are used as diincyanate components because the polyurethane-modified polyurethane-modified polyurethane obtained using other diisocyanates has good weather resistance and cold resistance. This is because it is possible to produce a polyurethane-modified vinyl chloride polymer that has excellent physical properties compared to polyurethane-modified vinyl chloride polymers that have insufficient physical properties such as flexibility and transparency.

The reason for using the above-mentioned polyester diol as a polyol component is that other polyols have problems with the physical properties such as stickiness, flexibility, cicada resistance, and hydrolysis resistance of the resulting polyurethane-modified vinyl chloride polymer. This is because the reaction ratio between the polyester diol obtained in this way and the aliphatic alicyclic diisocyanate is 1% of the diisocyanate component.
It is preferable to react at a ratio of 0.95 to 1.05 moles of the diol component per mole.

The polyurethane resin used in the present invention has a resin solid content of 20
When made into a 1% MUFd solution in methyl ethyl ketone, the viscosity at 25°C is 2 fl'-2,000 c p [+, especially 5
A speed of 0 to 1,000 cps is preferable. If the viscosity is 200 plI or less, the processability and various physical properties of the produced polyurethane-modified vinyl chloride polymer will be affected.
Q occurs, and those with 2,0000 cps or more have problems with solubility in vinyl chloride monomers.

The vinyl chloride monomer in which the vinyl chloride monomer-soluble thermoplastic polyurethane is dissolved is subjected to 111 polymerization by a polymerization method used in a conventional method for producing a vinyl chloride polymer.

Namely, ■ suspension polymerization method, ■ emulsion polymerization method, ■ solution stone ft method,
■Polymerized by bulk method, ■precipitation method, etc.).

Among these, the most preferred is 1. For <, the emulsification method is used.

In the suspension polymerization method, for example, vinyl chloride monomer, thermoplastic polyurethane, and a polymerization initiator are dissolved in a reaction vessel, and water containing a suspending agent is mixed all at once into the solution. Polymerization is carried out in the system, or ■vinyl chloride monomer,
Polymerization is performed in a dispersion system formed by mixing thermoplastic polyurethane, a polymerization initiator, a suspending agent, and water in a container L5. The polymerization is carried out in a dispersion formed by dropwise addition to water containing a suspending agent in a reaction vessel. In either case, it is preferable to carry out the polymerization at a temperature of 60 to 70°C.

The polymerization initiator referred to here is a radical catalyst. For example, diacyl oxides such as benzoyl peroxide, lauroyl peroxide, etc.; diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, bis-(4-tert-butylhexyl) peroxydicarbonate, etc. carbonates; tertiary-butyl peroxybivalate, tertiary-butyl peroxyoctoate, tertiary-butyl peroxyneodecanate, acetyl cyclohexane sulfate gualkyl peresters; cyclohexanone peroxide, tertiary-butyl peroxide; - Ketone peroxides or hydroperoxides such as butyl hydroperoxide: α,α'-azobisisobutyronitrile, 2,2'-azobis-2,4
Examples include azo compounds such as -dimethylvaleronitrile and the like. Preferably, azo compounds such as α, d-azobisisobutyronitrile and 2,2'-azobis-2,4-dimethylvaleronitrile are used. These radical catalysts may be used alone or in combination. These are used in amounts of 0.001 to 5% by weight with respect to vinyl chloride monomer. these are.

It may be added dropwise at the start of the reaction, or it may be added to the aqueous medium or vinyl chloride monomer solution in advance.

Further, the suspending agent may be one that is normally used in the suspension multiplication method. For example, water-soluble polymers such as polyvinyl alcohol, incompletely saponified polyvinyl alcohol, water-soluble cellulose ethers, vinyl acetate-maleic anhydride copolymer, styrene-maleic anhydride copolymer, etc., calcium carbonate, sulfuric acid, etc. One or more water-impossible solid powders such as barium, calcium phosphate, talc, bentonite, etc. Furthermore, fatty heavy soaps, anionic surfactants such as sodium alkyl sulfate, sodium alkyl sulfonate, sodium alkylbenzene sulfonate, etc., nonionic surfactants such as sorbitan alkyl ester, polymexyethylene alkyl ether or its ester, etc. Activators may be used in combination, and these may be used in an amount of 0.01 to
It is used in an amount of 5% by weight.

Even when the production method of the present invention is carried out by emulsion polymerization, the reaction components may be charged all at once into a reaction vessel and the polymerization reaction may be carried out, as in the case of the suspension polymerization method (also, the polymerization reaction may be carried out in advance by heating the The reaction may be carried out.The reaction temperature at this time is 6
Approximately 0 to 70°C is appropriate.

Examples of emulsifiers used in emulsion polymerization include anionic surfactants such as sodium alkyl sulfonates, sodium alkyl sulfates, sodium alkylbenzenesulfonates, alkyl ethers or esters of polyoxyethylene, sorbitan alkyl esters, and polyoxyethylene propylene. One or more types of nonionic surfactants such as glycol ether, commercial grade fatty acid, higher alcohol, etc. are used. Preferably, anionic surfactants such as sodium alkylbenzenesulfonates are used. Examples of the radical initiator used in this polymerization reaction include water-soluble azo compounds such as α,α'-azobisisobutyronitrile. These are used in amounts of 0.01 to 5% by weight relative to the monomer phase.

To the vinyl chloride monomer that dissolves the thermoplastic polyurethane, vinyl chloride monomer alone or vinyl chloride)lzmo/
We investigated the physical properties of polyurethane-modified vinyl chloride polymers that can be obtained by copolymerizing monomers such as vinyl acetate, acrylonitrile, vinylidene chloride, methyl acrylate, methyl methacrylate, styrene, ethylene, propylene, etc. Radical polymerization may be carried out within a range that does not cause damage. The composition weight ratio of the thermoplastic polyurethane resin and vinyl chloride in the polyurethane-modified vinyl chloride polymer of the present invention can be arbitrarily selected, but preferably L <G' lj is 70 to 30% by weight of the thermoplastic polyurethane resin based on 30 to 70 trillion % by weight of the vinyl chloride polymer. If the amount of thermoplastic polyurethane is less than 60 quintillion percent by weight, problems will arise in cold resistance and flexibility, and if it is more than 70 quintillion percent by weight, problems will arise in cost and molding process (1:).

The vinyl chloride polymer of the present invention has an oJ
Since it does not use plasticizers and is sufficiently transparent and soft, problems such as extraction, migration, and toxicity of plasticizers do not occur. Moreover, it has excellent strength and elongation, cold resistance, abrasion resistance, weather resistance, hydrolysis resistance, and processability. Furthermore, depending on the requirements, plasticizers, lubricants, stabilizers, fillers, pigments, flame retardants, antistatic agents, etc. can be added.

The polyurethane vinyl chloride polymer according to the present invention has hydrolysis resistance, weather resistance, cold resistance, flexibility, workability,
Excellent transparency.

Therefore, due to its excellent physical properties, it is useful for manufacturing food equipment, medical equipment or parts, packaging materials, general industrial equipment or parts, various molded products such as hoses, tubes, belts, sheets, films, etc. .

The present invention will be described in detail below according to synthesis examples and examples.
The present invention is not limited to these. Part 1 of the text
is based on weight.

(Synthesis of polyurethane and its physical properties) Synthesis Example 1 A polyester diol with a molecular weight of 2,000 was synthesized consisting of a mixed diol of 1.4-butane di, nyl and neopentyl glycol in a 90:10 molar percentage and adipic acid. . 1 mol of this polyester diol was heated to 70°C, 1 mol of hexamethylene diisocyanate was added, and after stirring at high speed, it was spread on a vat prepared in advance in a 160°C dryer, left for 30 minutes, and reacted. gave birth to a baby.

The polyurethane taken out from the dryer was cooled to room temperature and then passed through a pulverizer to form flakes. This flake sample was designated as polyurethane A.

Synthesis Example 2 1,6-
A polyester glycol having a molecular weight of 2,000 was synthesized in the same manner as in Synthesis Example 1 except that hexanediol was used. Polyurethane was synthesized in the same manner as in Synthesis Example 1.

The obtained polyurethane is flaked and polyurethane B
And so.

Synthesis Example 6 A polyester glycol having a molecular weight of 2.000 consisting of 1,4-butanediol and adipic acid was synthesized, and polyurethane flakes were obtained in the same manner as in the synthesis example.

This flake sample was designated as polyurethane C.

Synthesis Example 4 Polyurethane was synthesized in the same manner as in Synthesis Example 1 by using 1.03 moles of hegisamethylene diisocyanate in 1 mole of the polyester glycol synthesized in Synthesis Example 1. Polyurethane flakes were obtained. This product was designated as polyurethane D.

Synthesis Example 5 I'J was prepared in exactly the same manner as in Synthesis Example 1 except that 1 mole of 4,4'-diphenylmethane diisocyanate was used in place of hexamethylene diisocyanate.

The obtained polyurethane flakes were designated as polyurethane E.

Synthesis Example 6 A polyester glycol molecule i20[]D consisting of a 70:30 mol% mixed diol of 1,6-hexanediol and 1,6-butanediol and adipic acid was synthesized, and the following synthesis example 1 and Polyurethane flakes were obtained in a similar manner.

This flake sample was designated as Polyurethane F.

A part of the polyurethane flakes A-F synthesized in Synthesis Examples 1 to 6 was dissolved in methyl ethyl ketone so that the resin solid content was 20% by weight, and the viscosity of this solution was measured at 25°C using a B-type rotational viscometer. did. The results are shown in Table 1.

Examples 1 to 7 and Comparative Examples 1 to 2 Polyurethane A to F 1.000 parts, vinyl chloride monomer 1.00 [1 to 1.7 [10 parts, water 5.5 t] [l
i%l ~, α, Cf-6 parts of azodiisobutyronitrile (
Polymerization initiator) and 5 parts of polyvinyl alcohol (dispersant) were placed in an autoclave equipped with a stirrer, stirred at room temperature for 6 hours to dissolve the polyurethane, and then heated at 60°C for 15 hours.
Polymerized for hours. The resulting suspended product was heated under reduced pressure for 40 minutes.
It was dried at ℃ to obtain a powdery polymer.

These were polymers having the constituent components shown in Table 1. Next, 3 parts of epoxidized soybean oil, 1 part of calcium stearate, and 1 part of zinc stearate were added to 100 parts of this powdery polymer, and the mixture was placed on a steam-heated 8-inch mixing roll (steam pressure 6-7 kg□, roll temperature 140-150
℃) for 5 minutes, the sheet was taken out from the roll and press-molded into a sheet with a thickness of 2 mm. Also, as in the formulation of Comparative Example 2, polyurethane A and a commercially available vinyl chloride resin (p: 1050) were triblended, and 3 parts of epoxidized soybean oil,
1 part of calcium stearate and 1 part of zinc stearate were added, and a sheet having a thickness of 2 mm was press-formed through roll processing. All press conditions are as follows.

Pressing temperature: 150-160℃ Mold and sample heating: ls J de 5 minutes Press time and pressure = 100-120 kg Δ x 5 minutes Cooling time and pressure 110-130 kg/d x 5 minutes Physical property test molded sheet (2 mm ) was used to perform the following physical property tests.

1) Hardness: According to JIS-6501 2) Tensile strength: According to JIS K-6725 3) 100% modulus --- 〃5) #
I Abrasion property --- J Is K-7204 (Taper abrasion, abrasion '1m (S 1'7)) 6) Hydrolysis resistant machine --- Tensile strength after 2 weeks at 70°C x 95% RH Retention rate (%7) Low temperature embrittlement temperature...JIS K-/1723
8) Evaluation of peelability in roll processing The ease of peeling with two rolls was quantified as shown below, and the workability was expressed as fF.

0: The entire film adheres to the roll and cannot be peeled off without l- 1: The film peels off at a position of % of the roll circumference from the roll mixing section 3:
%〃5:
The results for K 7 and above are shown in Table 1.

Claims (1)

[Claims] A polyurethane-modified vinyl chloride obtained by dissolving a vinyl chloride monomer-soluble thermoplastic polyurecne resin obtained by reacting a polyester diol with an aliphatic or alicyclic diisocyanate, and then radically polymerizing the vinyl chloride monomer. Polymer.