JPH0513984B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a soft polyvinyl chloride resin (abbreviated as PVC) composition, and in particular, it relates to a soft polyvinyl chloride resin (abbreviated as PVC) composition, and in particular, it has properties such as processability, non-migration property, cold resistance, blocking property, etc. made of a mixture of PVC and polyurethane. This invention relates to a soft PVC composition with excellent properties. [Prior art and its problems] PVC is dioctyl phthalate (abbreviated as DOP)
Soft PVC compositions plasticized with various liquid plasticizers, including phthalate ester derivatives, are widely used as general-purpose plastics that are easy to process, such as wire covering materials, packaging materials, leather, tubes, etc. However, soft PVC is used in wire sheathing materials for precision equipment, leather for camera cases, food hoses, etc.
When using liquid plasticizers, the liquid plasticizer migrated or evaporated, reducing the performance of electronic components and fogging camera lenses. Therefore, there has been a desire for a non-volatile, non-migratory soft PVC composition that does not contain a liquid plasticizer while retaining the processability of PVC. Therefore, in order to create a non-volatile, non-migrating soft PVC composition, we used acrylonitrile-butadiene rubber, chlorinated polyethylene, ethylene-
Attempts have been made to apply vinyl acetate copolymer (abbreviated as EVA), thermoplastic polyurethane (abbreviated as TPU), etc. Blends with TPU are excellent for things that require oil resistance and cold resistance, such as electric wire covering materials and medical materials, and have been put into practical use (Special Publication No. 36896/1983). However, a transparent sheet made by blending low molecular weight TPU with PVC, which has a relatively low melt viscosity among TPUs, not only has poor processability because it sticks to the molding machine such as the roll surface during kneading, but also has poor processability. The product sheet was sticky and would stick if you stacked the sheets, etc., and the sheet would break if you tried to force it off. On the other hand, when high molecular weight TPU with relatively high melt viscosity is used and blended with PVC, the temperature range where PVC decomposition does not occur is
Because TPU is difficult to melt, it is not possible to obtain a molded product sheet that is compatible with the TPU, and even if it is forcibly molded, only a cloudy sheet with many fish eyes can be obtained. Graft polymerization has also been carried out by dissolving TPU in vinyl chloride monomer, but in this case as well,
Because TPU needs to be soluble in the vinyl chloride monomer, low molecular weight TPU is used, resulting in the same drawbacks as when blending TPU with low melt viscosity described above. [Means for Solving the Problems] Under such circumstances, the present inventors conducted extensive research in order to obtain a soft PVC resin composition free from the above-mentioned drawbacks. (abbreviated as VEE), in particular with modified VEE obtained by polymerizing vinyl monomers with a solubility coefficient (abbreviated as SP value) of 8.5 to 15 in the presence of VEE. With this method, PVC, TPU, and modified VEE can be easily molded, and the resulting molded product sheet is non-migration, and transparent and flexible molded products with excellent cold resistance, oil resistance, and non-adhesion can be obtained. This discovery led to the present invention. That is, the present invention provides (A) polyvinyl chloride, (B) a polyhydroxy compound having a molecular weight of 1000 to 5000,
It is obtained from a polyisocyanate compound and a chain extender, and its melt viscosity is 10 ⁴ to 10 ⁶ at 170°C.
100 parts by weight of a polymer composition consisting of a thermoplastic polyurethane, and (C) 5 to 50 parts by weight of a modified vinyl ester/ethylene resin,
The resin (C) is a vinyl ester/ethylene copolymer
It is obtained by copolymerizing 5 to 50 parts by weight of a polar vinyl monomer selected from (meth)acrylic acid, its alkyl ester, and styrene into the copolymer in the presence of 100 parts by weight. (C-1), and its solubility coefficient is 8.5 to 15 (C-2)
The present invention provides a flexible polyvinyl chloride resin composition characterized by the following. Component (A) used in the present invention includes vinyl chloride homopolymers and vinyl esters such as vinyl acetate,
Vinyl chloride containing olefins such as ethylene, alkyl esters such as acrylic acid and methacrylic acid, and monomers copolymerizable with vinyl chloride such as vinylidene chloride in a proportion of 30% by weight or less (hereinafter abbreviated as %). In addition, there are copolymers of ethylene/vinyl acetate, chlorinated polyethylene, and vinyl chloride/graft copolymers in which vinyl chloride is added to thermoplastic polyurethane. Any production method such as suspension polymerization, emulsion polymerization or bulk polymerization may be used, but in the present invention, polymerization with a degree of polymerization in the range of 600 to 1800 is used.
PVC is better. If the polymerization degree of PVC is less than 600, the strength of the composition will be low and the adhesiveness will be high;
If it exceeds, it is difficult to make it compatible with TPU and VEE.
It is opaque and has many black eyes. The TPU of component (B) is obtained as a reaction product of a polyhydroxyl compound and a polyisocyanate compound. The polyisocyanate may be any type of aliphatic and aromatic isocyanate, such as 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and the like. Examples of polyhydroxy compounds include hexahydroterephthalic acid, phthalic acid, isophthalic acid,
Aromatic and aliphatic dicarboxylic acids such as terephthalic acid, adipic acid, azelaic acid, sebacic acid and their acid esters, acid halides and 1,4-butanediol, 1,6-hexanediol, 1,3
- Condensation reaction with aliphatic diols such as propylene diol, 1,3-butylene diol, neopentyl diol, or ε-caprolactone, γ-
Examples include polyester diols obtained by ring-opening polymerization of butyrolactone, polyether diols such as polypropylene glycol, polytetramethylene glycol, polycarbonate diols, polyamide polyester polyols, polythioethers, and the like. As the chain extender, for example, polyhydric alcohols such as ethylene glycol, 1,4-butanediol, 1,6-hexanediol, ethanolamine, ethylenediamine, N-methyldiethanolamine, amines, amino alcohols, or water are used. It will be done. The polyhydroxy compound preferably has a relatively high molecular weight of 1000 to 5000, more preferably 1000 to 4000, from the viewpoint of cold resistance and processability, and the melt viscosity of the TPU is 10 ⁴ at 170°C. ~10 ⁶ poise (measured with Koka type flow tester) is good. Examples of the modified VEE of component (C) include copolymers of ethylene and vinyl esters such as vinyl formate, vinyl acetate, and vinyl versatate. Preferably from the viewpoint of processability, non-stickiness, transparency, etc.
It is obtained by polymerizing polar vinyl monomers with a solubility coefficient of 8.5 to 15 in the presence of VEE. Applicable VEE
(C) has an SP value of 8.5 in terms of workability, transparency, and oil resistance.
~15 (in particular, the amount of vinyl ester is 40 to 80%), preferably a copolymer of 8.7 to 9.7, and the polar vinyl monomer has an SP value of 8.5 to 15, specifically, for example, ethyl acrylate, ethyl acrylate , acrylic acid such as methyl methacrylate, methacrylic acid and its alkyl esters, styrene,
There are aromatic vinyls such as α-methylstyrene, etc.
Also, one or more of these vinyl monomers may be used in combination. The amount of the monomer added is 5% of the modified VEE (C).
A range of ~50% is preferred. The numerical limitations for the modified VEE above are for soft PVC
It is determined by the balance of physical properties such as processability, transparency, strength, oil resistance, cold resistance, and non-adhesiveness of the composition, and as the amount of vinyl ester in VEE decreases, the SP value decreases to less than 8.5. Processability, transparency, and oil resistance of the PVC composition deteriorate, and when the amount of vinyl ester increases and the SP value becomes higher than 15, cold resistance, processability, and non-stick properties deteriorate. The appropriate amount of modified VEE (C) to be added is 5 to 50 parts per 100 parts of the total amount of PVC (A) and TPU (B). If it is less than 5 parts, it will not be effective as a compatibilizer, and if it is more than 50 parts, cold resistance and strength will deteriorate. Modified VEE(C)
Although various polymerization methods such as solution polymerization, suspension polymerization, and bulk polymerization are possible, emulsion polymerization is preferred because it can increase the molecular weight of the composition from the viewpoint of strength and non-adhesiveness. Modified VEE (C) is obtained by polymerizing vinyl monomers in the presence of VEE. As the polymerization method, general methods such as polymerization in a molten state or in a molten state can be used, and for example, it is carried out as follows. After adding dispersants used in suspension polymerization to VEE latex, such as organic dispersants such as polyvinyl alcohol, polyvinylpyrrolidone, and methylcellulose, and organic dispersants such as calcium phosphate, calcium carbonate, and magnesium oxide, the solubility coefficient
After adding a polar vinyl monomer of 8.5 to 15 and allowing the VEE particles to absorb the monomer, the temperature is raised and polymerization is performed using a radical initiator. The polymerization temperature varies depending on the radical initiator used, but is generally 60 to 130°C.
Separate the generated suspended modified VEE (C) from water,
Wash and dry. In this case, an anti-blocking agent may be used. For example, wax, silicone oil, silica,
There are organic and inorganic compounds such as calcium carbonate, magnesium oxide, and calcium stearate.
10 parts can be added. In addition, the melt viscosity of modified VEE (C) is
It is desirable that the temperature is 10 ³ to 10 ⁵ poise at 170°C.
In addition, the solubility coefficient of the present invention is based on the Encyclopedia of
Polymer Science and Technology (Wiley-
(Published by Inter-Seience). In addition, the solubility coefficient of the multicomponent polymer was calculated assuming additive formation. Further, other polymer plasticizers and liquid plasticizers may be used in combination without departing from the spirit of the present invention. Furthermore, in addition to the above, stabilizers, fillers, lubricants, colorants, antioxidants, ultraviolet absorbers, flame retardants, crosslinking agents, and the like may be added as appropriate and necessary. The composition of the present invention can be molded using conventional Banbury,
This is done by rolling, extrusion, injection molding, etc. [Effects of the invention] The flexible PVC resin composition of the present invention has non-migration,
Not only is it excellent in cold resistance and strength, but it is also superior to conventional
It is possible to provide a molded product that is excellent in moldability, has less fish eyes, is transparent, and has less stickiness, which could not be obtained with a mixture of PVC and TPU or a combination of polymers outside the scope of the present invention. As described above, molded products made from the composition of the present invention can be used as wire coating materials for internal wiring, fire hoses, etc. where non-migration, cold resistance and adhesiveness are problems, or can be used as transparency, non-migration and adhesiveness. It can be applied to a wide range of fields, including packaging materials for precision equipment where safety is important, and medical materials such as blood packs, catheters, and Band-Aids. [Example] In order to further clarify the following characteristics of the present invention, the present invention will be specifically explained by giving examples. Note that all parts and percentages in Reference Examples, Examples, and Comparative Examples are based on weight. Reference example 1 Production of VEE 2 Sodium lauryl sulfate in autoclave 5
1.5 parts of methylcellulose dissolved in distilled water
Further, 500 parts of vinyl acetate and 560 parts of ethylene (excess rate 143%) were added, and 20 parts of a 10% potassium persulfate aqueous solution was added dropwise to react at 45°C for 4 hours to produce ethylene with a solid content of 875 parts. A latex containing a vinyl acetate copolymer was obtained. After adding an aqueous calcium chloride solution and aging at 80°C for 1 hour, the polymer was separated from the aqueous phase and dried at 50°C for 20 hours to give 830 parts.
VEE (referred to as resin) was obtained. VEE's SP value is 8.74
(vinyl ester amount: 56%), and the melt viscosity at 170°C was 8.5×10 ³ poise. Reference Example 2 Production of modified VEE 4 parts of calcium phosphate and distilled water were added to 445 parts (200 parts of solids) of the ethylene vinyl acetate copolymer latex (resin) of Reference Example 1 to make the solid content 20%.
To this aqueous dispersion was added 50 parts of methyl methacrylate (SP value 9.4) in which 1.0 part of benzoyl peroxide was dissolved at room temperature, and the mixture was kept under stirring for 1 hour to allow the vinyl monomer to be absorbed into the latex particles. . Subsequently, the temperature was raised to 75°C and reacted for 4 hours.
The temperature was further raised to 90°C and kept for 2 hours. When the temperature was lowered and stirring was stopped, the particle size was 0.2.
A bead-like precipitate of ~0.5 mm was obtained, which was washed with water and dried to obtain 238 parts of modified VEE (C) (referred to as resin). The SP value of modified VEE (C) was 8.87, and the melt viscosity was 1.5×10 ⁴ poise at 170°C. Reference Example 3 Production of modified VEE Except for Reference Example 2, 50 parts of methyl methacrylate was replaced with 30 parts of ethyl acrylate (SP value 9.2) in which 0.8 parts of benzoyl peroxide was dissolved and 10 parts of acrylonitrile (SP value 15). Bead-like precipitates with a particle size of 0.1 to 0.3 mm were obtained in the same manner as in Reference Example 2, washed with water and dried, resulting in 225 parts of modified
VEE (referred to as resin) was obtained. The modified VEE had an SP value of 8.70 and a melt viscosity of 1.1×10 ⁴ poise at 170°C. Reference Example 4 Production of modified VEE In Reference Example 2, vinyl versatate/ethylene copolymer (SP value 8.6, melt viscosity 3.8×10 ³ poise) was used instead of vinyl acetate/ethylene copolymer, and methyl methacrylate was used instead of vinyl acetate/ethylene copolymer. Reference example 2 except that methyl acrylate (SP value 9.7 was used instead of
Similarly, 241 parts of modified VEE (referred to as resin)
I got it. The modified VEE had an SP value of 8.82 and a melt viscosity of 9.1×10 ³ poise at 170°C. Reference Example 5 Commercially available ethylene vinyl acetate copolymer (SP) with a vinyl acetate content of 28% and a melt index of 15.
value 8.3, referred to as resin) was used. Example 1 170°C obtained by reacting 100 parts of PVC with a degree of polymerization of 1100, butanediol/adipate polyester diol with a molecular weight of 2000, and 1,4-butanediol and hexamethylene diisocyanate in a molar ratio of 1:3:1. Using a 6-inch mixing roll, 40 parts of TPU with a melt viscosity of 7.5 x 10 ⁵ poise, 30 parts of resin, and 3 parts of a fatty acid metal salt stabilizer (Gretsu MP-568C; manufactured by Dainippon Ink Chemical Co., Ltd.) were added.
The mixture was kneaded at 180°C for 10 minutes. The following items were evaluated as workability during roll kneading. (1) Miscibility: When the test compound was kneaded with two 6-inch rolls, if the compound could be wrapped around the rolls within 5 minutes and kneaded in 10 minutes, there would be no practical problem and the test was passed. (2) Roll tackiness: When kneading the test compound with two 6-inch rolls, if the compound can be peeled off with a spatula after being wrapped around the rolls, there is no practical problem, so it was passed. (3) Kneading sheet (0.5mm thick)
It was cut into 10 x 10 cm pieces, heat-treated in a gear oven at 180°C for 30 minutes, and then the number of dark brown spots was measured, and if it was less than 1, it was considered to have passed. Then, using a press molding machine at 180℃, 100Kg/cm ²
Press molding was carried out for 5 minutes at a pressure of 1 mm to obtain a sheet with a thickness of 1 mm. The following physical properties of the obtained sheet were evaluated. (1) Tensile strength: Measured according to JIS K-6723, 180
If Kg/cm ² or more, there is no practical problem, so it was passed. (2) Elongation at break: Measured according to JIS K-6723,
If it is 250% or higher, there is no practical problem, so it was considered a pass. (3) Oil resistance; measured according to JIS K-6723, 70℃
If the residual elongation after the 24-hour test is 85% or more, there is no practical problem, so the test was considered to have passed. (4) Transparency: The total light transmittance was measured using sodium light, and if it was 60% or more, there would be no practical problem, so it was passed. (5) Migration; sandwich the sheet between polystyrene plates,
After being left at 70°C for 24 hours under a load of 0.5 kg/cm ² , the presence or absence of substances transferred to polystyrene was observed. Those with no traces of migration were considered to have passed. (6) Cold resistance: -20 measured according to JIS K-6723
If the temperature is below ℃, there is no practical problem, so it was passed. (7) Non-adhesive: After laminating two sheets of 10 x 15 cm, press at 23℃ for 1 minute with a pressure of 30 kg/cm ² , and cut a 2 cm wide strip-shaped specimen from the laminated sheet. Created. The obtained specimen was pulled at a speed of 500mm/
A 180 degree peel test was carried out under the conditions of 5 kg/2 cm 2 or less, and a value of 5 kg/2 cm ² or less was considered to be a pass. (8) Heat resistance; measured according to JIS K-6723, 100
If the residual elongation after the 120-hour test at ℃ is 85% or more, there is no problem in practical use, so the test was passed. Example 2 Example 2 was conducted in the same manner as Example 1, except that 50 parts of the resin was changed from 30 parts in Example 1. The results are shown in Table 1. Example 3 Example 3 was conducted in the same manner as Example 2 except that resin was used instead of resin in Example 2, and the results are shown in Table 1. Example 4 Example 4 was conducted in the same manner as Example 2 except that resin was used instead of resin in Example 2, and the results are shown in Table 1. Example 5 Molecular weight instead of TPU used in Example 2
1000 polytetramethylene glycol and 1,4
Examples except that 70 parts of TPU with a melt viscosity at 170°C of 6.5×10 ⁵ poise was obtained by reacting butanediol and 4,4′-diphenylmethane diisocyanate in a molar ratio of 1:3:1. Example 5 was carried out in the same manner as in Example 2, and the results are shown in Table 1. Comparative Example 1 Comparative Example 1 was carried out in the same manner as Example 2 except that 40 parts of dioctyl phthalate was used instead of TPU and resin. The results are shown in Table 1. Comparative Example 2 Comparative Example 2 was prepared in the same manner as in Example 2 except that 50 parts of the resin was removed, and the results are shown in Table 1. Comparative Example 3 Molecular weight instead of TPU used in Example 2
2000 butanediol-adipate polyester and hexamethylene diisocyanate were reacted in a molar ratio of 1:1 using TPU with a melt viscosity of 1.5 x ¹⁰³ poise at 170°C, and 50 parts of the resin was removed. Comparative Example 3 was carried out in the same manner as in Example 2 except for this, and the results are shown in Table 1. Comparative Example 4 Comparative Example 4 was carried out in the same manner as Example 1 except that 40 parts of TPU used in Example 1 was used and 85 parts of resin was used instead of 30 parts of resin. The results are shown in Table 1. Comparative Example 5 50 parts of resin was used instead of 50 parts of resin in Example 2.
The results are shown in Table 1 as Comparative Example 5, which was carried out in the same manner as in Example 2 except that Comparative Example 6 Molecular weight instead of TPU used in Example 2
2000 butanediol/adipate polyester and 1,4 butanediol and 4,4'-diphenylmethane diisocyanate in a molar ratio of 1:4:1.
The melt viscosity at 170℃ obtained by reacting with
Comparative Example 6 was prepared in the same manner as in Example 2, except that 70 parts of ¹⁰⁷ poise TPU was used and 50 parts of the resin was removed. The results are shown in Table 1.

【table】

Claims (1)

[Claims] 1 (A) polyvinyl chloride, (B) a polyhydroxy compound with a molecular weight of 1000 to 5000,
It is obtained from a polyisocyanate compound and a chain extender, and its melt viscosity is 10 ⁴ to 170°C.
100 parts by weight of a polymer composition consisting of a thermoplastic polyurethane having a molecular weight of 10 ⁶ poise, and (C) 5 to 5 parts of a C-modified vinyl ester/ethylene resin.
50 parts by weight, and the resin (C) is a vinyl ester/ethylene copolymer.
It is obtained by copolymerizing 5 to 50 parts by weight of a polar vinyl monomer selected from (meth)acrylic acid, its alkyl ester, and styrene into the copolymer in the presence of 100 parts by weight. (C-1) and (C-2) a soft polyvinyl chloride resin composition having a solubility coefficient of 8.5 to 15. 2. The composition according to claim 1, wherein the polyvinyl chloride (A) contains 30% by weight or less of a copolymer component and has a degree of polymerization of 600 to 1,800. 3 Modified vinyl ester/ethylene resin (C) is
The composition according to claim 1, which has a melt viscosity of 10 ³ to 10 ⁵ poise at 170°C.