JPH0533271B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for producing a composite resin molded product made of vinyl chloride polymer and polyurethane, and more specifically, to a method for manufacturing a composite resin molded product made of vinyl chloride polymer and polyurethane. The present invention relates to a method for producing the above-mentioned composite resin molded product which is excellent and has a small thermal history.

Conventional technology Vinyl chloride polymers are industrially produced in large quantities, and are used not only for molded products for various hard industrial materials, but also for impact resistance and other products by adding plasticizers such as dioctyl phthalate and dioctyl adipate. It has variable flexibility and is widely used as flexible molded products such as films, sheets, various hoses, belts, covered electric wires, leather, medical equipment parts, and daily miscellaneous goods.

However, in softened vinyl chloride polymer molded products, there are problems with changes in physical properties due to plasticizer transfer and contamination due to transferred plasticizer, and oil resistance and
Its uses are limited because it has drawbacks in heat resistance, safety and hygiene, etc.

As a method for solving the above-mentioned difficulties, modification of vinyl chloride polymers with polyurethane has conventionally been carried out. This is because polyurethane is highly flexible and has excellent mechanical strength, as well as excellent oil resistance and impact resistance at low temperatures.

As the above-mentioned modification means, it is already known to polymer blend a vinyl chloride polymer and a thermoplastic polyurethane (Japanese Patent Publication No. 53-29705). However, vinyl chloride polymer and thermoplastic polyurethane have different softening temperatures, making kneading difficult. It is necessary to keep it. Therefore, as the above-mentioned polyblend products are heated at high temperatures for a long time to become molded products, the vinyl chloride polymer, which has a low thermal decomposition temperature, deteriorates or becomes discolored, which significantly reduces the commercial value of the molded products. There was a problem.

However, as such a polyblend product, for example, a thermoplastic polyurethane (polybutylene adipate diol/diphenylmethane-4,4'- After melt-kneading 30 parts by weight of diisocyanate/1,4-butanediol composition using a screw type extruder, the resulting product was injection molded and had a Shore A hardness of 73.
So, straight vinyl chloride polymer is softened to the same hardness with dioctyl phthalate plasticizer,
They exhibit approximately the same elongation rate (approximately 250%) and are excellent in tensile strength, impact resistance at low temperatures, abrasion resistance, etc., and also have the disadvantages of plasticizer migration, namely:
Less likely to cause problems such as changes in physical properties or contamination during long-term use.

Therefore, if a method with a small thermal history can be applied to modify vinyl chloride polymer with polyurethane, products with high performance and commercial value can be obtained. has been attempted.

One example is a method in which thermoplastic polyurethane is dissolved in vinyl chloride monomer, and the monomer is then subjected to suspension polymerization in an aqueous system to obtain a polyurethane-modified vinyl chloride polymer powder, which is then subjected to molding ( Special Publication No. 60-30688). in this way,
A polyurethane-modified vinyl chloride polymer with a low thermal history can be obtained, but the thermoplastic polyurethane that dissolves in the vinyl chloride monomer has a very limited composition and is generally soft and has a low softening point, so the manufacturing process is difficult. However, there was a problem in that troubles due to adhesion were likely to occur. In addition, in the denaturation by the above method,
There is also a limit to the amount of polyurethane component that can be added to the vinyl chloride polymer, and from this point of view as well, it is difficult to diversify the composition.

Another example of modification is to impregnate vinyl chloride polymer powder with a component capable of reacting with isocyanates, such as polyester polyol or polyether polyol, and then heat it by melt-kneading it in a roll, extruder, or injection molding machine. There is a method of molding while reacting with polyisocyanate in an interforming machine (Japanese Patent Publication No. 59-39464). Although it is possible to obtain a polyurethane-modified vinyl chloride polymer molded product with a small thermal history by this method, it is difficult to produce high molecular weight polyurethane with this method.
The physical properties are inferior to those of the above two methods using pre-polymerized polyurethane, and the crosslinking reaction of the polyisocyanate may produce a fish-eye gel, and the molded product may become cloudy due to blooming or bleeding of unreacted polyols. There are problems with the appearance of the product, such as the surface being sticky or sticky.

The problem that the invention seeks to solve The objects of the present invention are as follows.

(1) To obtain molded products with excellent impact resistance and flexibility by modifying vinyl chloride polymer with completely polymerized polyurethane.

(2) To obtain a molded product with high commercial value made of a polyurethane-modified vinyl chloride polymer with little heat history.

(3) To modify vinyl chloride polymer using various polyurethanes with different properties such as hardness and softening point, and to obtain molded products with various performances.

Means for Solving the Problems The present invention was made as a result of extensive research in order to achieve the above-mentioned object. By using
The inventors have discovered that the problems of the conventional art can be solved, leading to the present invention.

That is, the present invention relates to a method for producing a molded article by hot molding using a resin molding material, and a resin molded article using a vinyl chloride polymer powder impregnated with a polyurethane emulsion as the resin molding material. The present invention relates to a manufacturing method.

The present invention also includes adding a stabilizer, a blowing agent, a pigment, a plasticizer, a filler, etc. to the resin molding material as necessary, pre-kneading it before molding, and using this to manufacture a resin molded product. It is about the method.

The vinyl chloride polymer powder used in the present invention is
It is a vinyl chloride homopolymer powder, or a copolymer powder of vinyl chloride and a small amount of one or more copolymerizable monomers, and its production method is, for example, by emulsion polymerization or suspension polymerization. Something,
Powder consisting of single particles with a diameter of approximately 0.5 to 10 microns,
Alternatively, it is a powder consisting of porous particles with a diameter of about 10 to 100 microns, which are agglomerated single particles with a diameter of about 0.5 to 10 microns. Among these, a powder consisting of porous particles of about 30 to 80 microns in diameter obtained by suspension polymerization is particularly suitable because it is easy to impregnate and adhere to the polyurethane emulsion.

Monomers that can be copolymerized with vinyl chloride in the above include α-olefins such as ethylene and propylene, vinyl esters such as vinyl acetate and vinyl stearate, vinyl ethers such as methyl vinyl ether and lauryl vinyl ether, and methyl acrylate. , esters of acrylic acid and methacrylic acid such as methyl methacrylate, amides such as methacrylamide and acrylonitrile, nitriles,
Styrenes such as styrene and α-methylstyrene,
and polyfunctional monomers such as diallyl phthalate and ethylene glycol dimethacrylate.

The polyurethane emulsion in the present invention is
They are nonionic, anionic, and cationic, and are produced by the methods described below.

(1) Phase inversion emulsification method Polyester diol or polyether diol, low molecular weight diol or diamine, and diisocyanate are reacted to synthesize a high molecular weight linear polyurethane, which is then dissolved in an organic solvent such as toluene, acetone, or tetrahydrofuran. death,
An aqueous emulsifier solution is added dropwise to this and stirred to force emulsification. Afterwards, the organic solvent may be removed by distillation. This gives a nonionic emulsion.

(2) Prepolymer method A prepolymer having terminal isocyanate groups is emulsified in water using an emulsifier and mechanical stirring. Next, it is reacted with a chain extender at the emulsion particle interface to form a polymer. Depending on the type of emulsifier, either nonionic, anionic or cationic emulsion can be obtained.

(3) Self-emulsification method This is a method in which a hydrophilic group or a hydrophilic molecular chain is introduced into a polymer to make the polymer self-emulsifying, thereby obtaining a polyurethane emulsion without using an emulsifier.

For example, a prepolymer having a terminal isocyanate group is reacted with an alcohol having a tertiary amino group (e.g., dimethylethanolamine, N-hydroxyethylmorpholine, etc.) or a polyamine (e.g., dimethylhydrazine, dimethylethylenediamine, etc.), Quaternizing agents (e.g., alkyl halides such as methyl bromide, ethyl chloride, acid halides such as acetyl chloride, benzoyl chloride, esters such as methyl p-toluenesulfonate, carboxylic acids, phosphoric acid, hydrochloric acid, sulfuric acid, etc.) (acids) and stirred in water to self-emulsify. In this method, cationic emulsions are obtained.

In addition, polyamino compounds having a group consisting of a prepolymer having terminal isocyanate groups and an alkali metal carboxylate or sulfonate (for example, sodium 2,5-diaminobenzoate,
(sodium 3,6-diaminonaphthalenesulfonate, etc.) is reacted and stirred in water to self-emulsify. In this method an anionic emulsion is obtained. In addition, a method of reacting a polyol with a carboxyl group or a sulfonic group with a polyisocyanate, and then pouring it into water containing caustic soda and stirring to self-emulsify it, and a method of reacting a polyisocyanate with a sulfonic acid group with a polyol, There are methods such as quaternary salting of the sulfonic acid groups in polyurethane with a tertiary amine, and at the same time pouring into water and stirring to self-emulsify; all of these methods yield an anionic emulsion.

The polyisocyanate used in the production of the above emulsion is R(NCO) ₂ (wherein R is organic 2
Represents a functional group. ) are suitable. Particularly preferred diisocyanates are those represented by the above general formula,
Representative examples include tetramethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, dodecamethylene diisocyanate, cyclohexane diisocyanate, 1-isocyanate-3-isocyanate methyl-3,5,5-trimethylcyclohexane, dicyclohexylmethane diisocyanate, xylylene diisocyanate, phenylene diisocyanate, 2,4- and 2,6-diisocyanate toluene and isomer mixtures thereof,
Examples include 2,4'- and 4,4'-diisocyanate diphenylmethane and isomer mixtures thereof, 1,5-diisocyanate naphthalene, and the like.

The polyol used in the preparation of the emulsion has a molecular weight of 300 to 6000, preferably 500 to 3000, is difunctional in the isocyanate polyaddition reaction, and contains an amount that is reactive with the isocyanate. These include dicarboxylic acids (e.g. succinic acid, adipic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid, etc.) and diols (e.g. ethylene glycol, propanediol, diethylene glycol, 1,3- and 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, dihydroxypolyesters known in polyurethane chemistry obtained from polyurethane (1,4-bis(hydroxymethyl)cyclohexane, etc.); polylactones known in polyurethane chemistry, such as ε-caprolactone and δ-valero using the above-mentioned diols as initiators; Polymers for addition polymerization of lactones, etc., polyethers known in polyurethane chemistry, for example, as divalent initiator molecules, water, the above diols, monoamines having primary amino groups, diamines having secondary amino groups , polymers obtained by ring-opening polymerization of styrene oxide, ethylene oxide, propylene oxide, tetrahydrofuran, epichlorohydrin, etc. produced using amino alcohol, etc.
or copolymers, polyacetals known in polyurethane chemistry, such as those obtained from the diols mentioned above and formaldehyde, polycarbonates known in polyurethane chemistry, for example polymers obtained from the diols mentioned above and diphenyl carbonate or dialkyl carbonate, polyurethane chemistry. Other polyols known in the art include ricinoleates of diols, polydiene polyols, polyolefin polyols, polysiloxane polyols, and the like.

Particularly suitable polyols include dihydroxy polyester, dihydroxy polylactone,
dihydroxy polyether and dihydroxy polycarbonate.

Moreover, instead of using the above-mentioned high-molecular-weight polyols, it is also possible to use exclusively low-molecular-weight polyols with a molecular weight of 300 or less, or a mixture of the high-molecular-weight polyols and the low-molecular-weight polyols.

Furthermore, trifunctional or higher-functional polyols or polyisocyanates can also be used in amounts below the limit that do not interfere with emulsion production.

In the method of the present invention, the resin molding material that can be used is one obtained by impregnating and adhering 100 parts by weight of vinyl chloride polymer powder to 10 to 110 parts by weight of the resin in the polyurethane emulsion.

In the above case, if the polyurethane resin content is less than 10 parts by weight, no improvement in performance such as flexibility or impact resistance will be observed. If the amount exceeds 110 parts by weight, the molding material becomes sticky and difficult to handle during molding.

The resin molding material used in the method of the present invention consists of vinyl chloride powder and polyurethane emulsion.
Continue mixing at a temperature of 100℃ using commonly used mixing equipment such as a ribbon blender, Henschel mixer, Nauta mixer, planetary mixer, pony mixer, Warner type kneader, Banbury type mixer, etc. until uniform impregnation is achieved. However, it is also possible to mix the mixture while removing evaporated components such as water under reduced pressure, or while pressurizing the mixture with a pressure plate.

Thereby, depending on the ratio of the vinyl chloride polymer powder to the polyurethane emulsion, it can be obtained in the form of powder, clay, or slurry.

In addition, in the above, if necessary, it may be mixed with stabilizers, blowing agents, pigments, plasticizers, fillers, and other additives known in the vinyl chloride industry and used immediately for molding, or it may be used in an extruder, Banbury, etc. It is used for molding after undergoing a melt-kneading process using a mold mixer or other suitable kneading equipment.

The molded product obtained by the method of the present invention is obtained by drying the resin molding material at a temperature of 50 to 120°C as necessary, and
It can be molded by virtually any method commonly used for thermoplastic resins. For example, the sheet-like material that is pulled out after applying calender processing can be made into a product as it is by passing through a take-up roll, etc., but it can also be laminated onto textiles or canvas and pressed and laminated with the rolls of a calender machine. It can be efficiently made into a sheet. By injection and compression molding, molded articles are obtained. Extrusion produces films, tubes, and shapes with complex cross-sections. In this case, crosshead extrusion is also possible for coating hoses, wires and other substrates. Powdered molding compounds can be used for coating, adhesive processing such as dipping, transfer, roller and knife coating. The same molding method as that for powder molding materials can be applied to slurry or plastisol molding materials.

Field of Application of the Invention The method of the present invention can be used to manufacture products such as window frames, automobile interior parts, support columns, gaskets, hoses, leather, agricultural films, blood transport pipes, blood bags, electric wire covering materials, conveyor belts, shoe soles, etc. It can be applied to many industries and is extremely useful from an industrial perspective.

EXAMPLES The present invention will be explained below with reference to Examples. Note that "parts" and "%" in the examples represent weight percentages unless otherwise specified.

Example 1 Paraprene 22S (thermoplastic polyurethane elastomer, manufactured by Nippon Polyurethane Industries) pellets 100
After dissolving 1 part in a mixed solvent consisting of 80 parts of tetrahydrofuran and 120 parts of acetone, 5 parts of Monogen Y-500 (sodium lauryl sulfonate emulsifier, manufactured by Daiichi Kogyo Yakuhin) were added, and 250 parts of water was added while stirring vigorously with a homogenizer. It was added dropwise and emulsified. Tetrahydrofuran and acetone are distilled off from this emulsion to obtain an aqueous dispersion with a solid content of 40%.

100 parts of the above aqueous dispersion, 200 parts of Lieuron 700D (suspension polymerized vinyl chloride polymer, manufactured by Toyo Soda Kogyo),
Two parts of calcium stearate and two parts of zinc stearate are mixed in a ribbon blender to obtain a polyurethane emulsion-impregnated vinyl chloride polymer powder. When the above powder is kneaded with two kneading rolls heated to 150°C, a translucent milky white sheet is obtained after water is evaporated. This sheet is pressurized with a press heated to 150℃ to create a smooth surface of 1 mm.
It was made into a thick sheet. Sheet physical properties are 100% modulus 180Kg/cm ² , tensile strength 350Kg/cm ² , elongation 250%
This sheet did not break even when folded. The appearance of the sheet was milky white and translucent, with no thermal yellowing observed at all.

Comparative example 1 40 parts of Paraprene 22S pellets, Lieuron
200 parts of 700D, 2 parts of calcium stearate and 2 parts of zinc stearate were mixed by shaking in a container,
Kneading was started using two kneading rolls heated to 150℃, but in order to form a sheet, the rolls had to be changed.
The temperature had to be raised to 160°C. This sheet was pressed with a press heated to 155°C to form a 1 mm thick sheet with a smooth surface. Sheet physical properties are 100% modulus 175Kg/cm ² and tensile strength 370
Kg/cm ² and elongation of 270%, showing almost the same physical properties as the sheet of Example 1, but the sheet appearance was translucent yellowish brown and had noticeable thermal yellowing.

Example 2 100 parts of Igelax 4040N (solid content 50%, anionic polyurethane emulsion, manufactured by Hodogaya Chemical Industry), 200 parts of Lieuron 700D, 2 parts of barium stearate and 1 part of dibutyltin dilaurate were mixed in a ribbon blender, A polyurethane emulsion-impregnated vinyl chloride polymer powder is obtained. This powder was dried for 30 minutes using a tumbler type dryer that can be heated to 105°C. This molding material was molded using a screw in-line injection molding machine (L/D=20/1, screw rotation speed 40 rpm). The molds were for tensile test specimens and impact test specimens and had a flat gate. Molding conditions are compression ratio 3.2, injection pressure
1000Kg/cm ² , cylinder temperature 165℃, mold temperature 55
It is ℃. The molding material could be fed smoothly using the hopper during injection molding, and the molded product had a uniform milky white appearance. The physical properties of the molded product are 100% modulus 150Kg/cm ² and tensile strength 240
Kg/cm ² , elongation was 290%, and Izotsu impact strength (with notches) was 5.5 Kg/cm/cm. The physical properties of Ryuron 700D, which was molded under almost the same conditions as above, were a tensile strength of 590 Kg/cm ² , an elongation of 9%, and an isot impact strength (notched) of 0.5 Kg·cm/cm.

Comparative example 2 40 parts of Paraprene 22S pellets, Lieuron
200 parts of 700D, 2 parts of barium stearate, and 1 part of dibutyltin dilaurate were mixed by shaking in a container, and injection molding was performed in the same manner as in Example 2.
Molding became possible by changing the cylinder temperature to 175°C. The appearance of the molded product was non-uniform, indicating that the polyurethane component and vinyl chloride polymer were not sufficiently mixed.

Example 3 The molding material of Example 2 was heated in a single screw extruder (L/D=
22/1, screw rotation speed 32 rpm) and cut into strands to obtain pellets for molding. Injection molding was carried out in the same manner as in Example 2 using this molding material. The molded product has a uniform milky white appearance, and its physical properties are 100% modulus 147Kg/cm ² , tensile strength 260Kg/cm ² , elongation 310%,
Izotsu impact strength (with notch) 5.7Kg・cm/cm
It was hot.

Example 4 Nitsuporan 4070 (polyester diol, hydroxyl value 56.0, acid value 0.3, manufactured by Nippon Polyurethane Industries)
200g and 10g of Adeka Polyether CM294 (polyether diol, hydroxyl value 39.5, manufactured by Asahi Denka Kogyo)
was charged into a closed reaction vessel and dehydrated by stirring for 30 minutes at 100°C under 10 mmHg vacuum.
Add 40 g of hexamethylene diisocyanate and stir at 100° C. until the isocyanate group content of the contents reaches 4.5% to react. Next, the above contents were cooled to 65°C, and then anhydrous acetone was added.
Add 200 g, then 4 g of N-methyldiethanolamine, and stir at 65°C for 2 hours. Furthermore, 100 g of acetone and 1-aminomethyl-5-amino-
Add 11 g of 1,3,3-trimethylcyclohexane, stir at 65°C for 2 hours, and then dilute with 100 parts of acetone. Isocyanate group content in solution is 0.02
After reaching milliequivalents/g or less, add 10 g of orthophosphoric acid (concentration 85%). Next, 500 g of water heated to 50° C. is added and stirred vigorously to emulsify, and then the acetone is distilled off using a water jet pump to obtain a cationic polyurethane emulsion with a solid content of 35%.

150 parts of the above emulsion, 50 parts of Lieuron 720 (emulsion polymerized vinyl chloride polymer, manufactured by Toyo Soda Kogyo),
One part of zinc stearate and one part of barium stearate were mixed in a planetary mixer to obtain a slurry.

Next, the slurry-form molding material was applied onto a polyester canvas using a doctor knife, and the mixture was passed through an oven heated to 110° C. for 3 minutes. The same operation was performed twice to adjust the coating thickness to 300μ. Next, the film was passed through an oven heated to 180°C for 6 minutes to melt the coating film, then cooled and rolled up. The resulting resin-coated impregnated canvas has excellent flexibility and a uniform milky white color on the coated surface, making it suitable for use as conveyor belts, packaging materials, and building materials.

Example 5 Izerax 4040N 100 copies, Reeuron 720
200 parts, 2 parts of epoxidized soybean oil, 1 part of calcium stearate, 1 part of zinc stearate, 0.1 part of carbon black, 0.5 part of phthalocyanine green pigment
Place the sample in a planetary mixer and heat to 105℃.
The mixture was kneaded for 30 minutes under a reduced pressure of 10 mmHg. Next, the contents
After cooling to 30°C, 150 parts of dioctyl phthalate was added and kneaded for 5 minutes to obtain a viscous sol.
This material was applied onto a polyester canvas using a doctor knife (area weight: 150 g/m ² ), and passed through an oven at 180° C. for 6 minutes to obtain a resin-impregnated canvas. This canvas has excellent flexibility and is impermeable to water, making it suitable as a waterproof fabric.

Effects of the Invention According to the method for producing a molding material according to the present invention, there is no coloration or deterioration due to heat during the production process, and the hardness can be adjusted to any desired level, and at the same time, the use of plasticizers can be eliminated or the amount used can be reduced. In order to reduce the amount of carbon dioxide, it has the effect of imparting excellent physical properties such as oil resistance and heat resistance. Further, since the resin can be easily mixed, resin deterioration during molding can be reduced, and at the same time, the molding process can be simplified.

Claims (1)

[Claims] 1. In a method for producing a molded article by hot forming using a resin molding material, the resin molding material is obtained by impregnating and adhering a polyurethane emulsion to vinyl chloride polymer powder. Characteristic method for manufacturing resin molded products. 2. The method according to claim 1, wherein the resin molding material is pre-kneaded with stabilizers, blowing agents, pigments, plasticizers, fillers, etc. as necessary.