JPH0248025B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a very soft vinyl chloride resin composition. More particularly, the present invention relates to such a composition comprising a vinyl chloride resin, a plasticizer, and a powdered plasticizer coated with a molecular film. Known soft vinyl chloride resin compositions can be used to freely adjust the hardness of the final molded product within a certain range by changing the proportion of plasticizer in the composition, so they can be used for automobile parts, electrical appliances, etc. It is heavily used for industrial products, etc. However, there is a certain limit to the lower limit of the aforementioned hardness, and the composition cannot replace rubbery materials in certain molded articles in the rubber field. The main reason for this is that there is a limit to the amount of plasticizer that vinyl chloride resins can absorb and retain. In other words, even if more than the limit amount of plasticizer is blended with vinyl chloride resin, the plasticizer will only adhere to the surface of the vinyl chloride resin powder that has already absorbed up to the limit amount of plasticizer, and the composition will not be uniformly mixed. It's impossible. Furthermore, if an amount of plasticizer exceeding the adhesion limit is added, that amount of plasticizer will separate to the bottom of the mixer where the mixing was carried out,
Alternatively, it becomes a paste-like mixture of non-uniform liquid and particles. It is impossible to carry out conventional molding processes such as extrusion molding, calendar molding, injection molding, etc. of vinyl chloride resin compositions using such a non-uniform composition. To summarize the above, it is impossible to mold a vinyl chloride resin composition containing an amount of plasticizer that cannot be normally absorbed by the vinyl chloride resin. However, on the other hand, there is a demand for a so-called extremely soft vinyl chloride resin composition that can produce molded products having the same hardness as the aforementioned molded products in the rubber field. The reason is that the soft vinyl chloride resin composition has material properties (for example, secondary processability and weather resistance) that rubber molded products do not have. In order to overcome the hardness limit of the above-mentioned soft vinyl chloride resin composition, the following proposals have been made. One of these is the internal plasticization of the vinyl chloride resin itself, which basically involves combining vinyl chloride monomers with relatively small amounts of other vinyl monomers such as vinyl esters, vinyl ethers, or α-olefins. This method uses a polymerized copolymer resin. However, these vinyl monomers have poor plasticization efficiency as a component of the copolymer resin, and the absorption amount of a plasticizer added to the copolymer resin from the outside is also considerably reduced. Therefore, even if a plasticizer is added up to the limit amount, a composition that gives a molded article with a hardness of 40 or less cannot be produced. Another method is to produce porous particles that absorb a large amount of plasticizer as a vinyl chloride resin.
However, the development of such particles has not yet resulted in a satisfactory product. As a result of intensive research to overcome the drawbacks of the prior art, the present inventors have developed a method for producing a vinyl chloride resin composition by mixing vinyl chloride resin and a plasticizer in a mixer. By using a plasticizer coated with a polymer film that does not disintegrate under the mixing conditions (mixing temperature and stirring force) together with a normal plasticizer, it is possible to achieve a hardness of 40 or less (note) that can be handled industrially. The present invention was completed by obtaining a composition (after molding) and confirming that extrusion molding and calendar molding using this composition were possible. As is clear from the above description, an object of the present invention is to provide an extremely soft vinyl chloride resin composition that provides a molded product with a hardness of 40 or less that can be substituted for molded products in the rubber field. The present invention has the following main configuration (1) and the following embodiment configuration (2). (1) 100 parts by weight of a vinyl chloride resin, 50 to 200 parts by weight of a plasticizer, and 50 to 99% by weight of a monomer of the following general formula () as a resin for forming a polymer film and the general formula ()
A powdery plasticizer coated with a polymer film made of a copolymer obtained by copolymerizing 50 to 1% by weight of monomers, wherein the powdery plasticizer constitutes the film. An ultra-soft vinyl chloride resin composition comprising 50 to 200 parts by weight of a polymer film-forming resin of 5 to 30 parts by weight and 95 to 70 parts by weight of a plasticizer coated with the film. General formula () CH ₂ = CX-COOR However, X is H, CH ₃ , R is H, CH ₃ -(CH ₂
-CH ₂ -) _o H, where n = 1 to 18 General formula ()

[Formula] However, X is H, Cl, and Y is Cl (2) The above general formula () is used as a polymer membrane forming resin.
50 to 99% by weight of the monomer of the general formula () and 50 to 1% by weight of the monomer of the general formula (), a total of 100% by weight and ()
as 1,4-hexazine, 2-methyl-1,
4-pentadiene, cyclopentadiene, 1,
5-cyclooctadiene, 4,7,8,9-tetraviroindene, 1,2,4-trivinylcyclohexane, 5-methylene-2-norbornene, 5-butene-2-norbornene, 5-ethylidene-2- Item (1) above, which uses a multicomponent copolymer obtained by copolymerizing one or more monomers selected from norbornene in an amount of 0 to 10% by weight based on the total amount of () and () above. Compositions as described. Hereinafter, the structure and effects of the present invention will be explained in detail. (a) Vinyl chloride resin: In general, the amount of plasticizer absorbed by vinyl chloride polymers differs depending on the degree of polymerization, and it is said that the amount of plasticizer absorbed is low in products with a low degree of polymerization and high in products with a high degree of polymerization. Even if the vinyl chloride resin is a high-polymerization product, the maximum amount of plasticizer that can be mixed therein is 200 parts by weight (hereinafter referred to as PHR) per 100 parts by weight of the resin. The hardness of the molded product obtained by molding a vinyl chloride resin composition containing 200 PHR of plasticizer exceeds 40. In order to obtain a molded product with a hardness of 40 or less, the powdered plasticizer coated with the polymer film-forming resin described in (2) above must be blended with the vinyl chloride resin in combination with a single plasticizer. No. The vinyl chloride resin used in the composition of the present invention may be a resin obtained by suspension polymerization, bulk polymerization, or emulsion polymerization, and is not particularly limited by the polymerization method. Preferably, use of a product with a high polymerization degree of 1800 or more obtained by suspension polymerization contributes to improvement of various physical properties. (b) Polymer film-forming resin: This resin is a copolymer of 50 to 99 parts by weight of the monomer of the following general formula () and 50 to 1 part by weight of the monomer of the general formula (). Furthermore, 0 to 10 parts by weight of one or more monomers selected from the group of the following monomers () are used in combination with 100 parts by weight of () and () to form a multi-component copolymer. You can also do it. General formula () CH ₂ = CX-COOR, X is H, CH ₃ , R is H, CH ₃ , -
(CH ₂ −CH ₂ )n−H, where n=1 to 18 General formula ()

[Formula] However, X is H, Cl, and Y is Cl.
Linear non-conjugated dienes such as 1,4-pentadiene, monocyclic dienes such as cyclopentadiene and 1,5-cyclooctadiene, 4,7,8,
Bicyclic dienes such as 9-tetraviroindene,
These include polyalkenylcycloalkanes such as 1,2,4-trivinylmicrohexane, and norbornene dienes such as 5-methylene-2-norbornene, 5-butene-2-norbornene, and 5-ethylidene-2-norbornene. When the above-mentioned polymer membrane is composed of a copolymer containing more than 99% by weight of the compound of the general formula () and less than 1% by weight of the compound of the general formula (), the strength of the membrane is improved and powder-like It is possible to improve the encapsulation rate of the plasticizer in the plasticizer, but when such a powdered plasticizer is mixed with a vinyl chloride resin and a plasticizer to form a molded product, the film surface of the powdered material is Since it is not compatible with the plasticized vinyl chloride resin portion of the surface, it remains as spots (note, "spots" in the examples below) in the molded product. On the other hand, when the above-mentioned polymer membrane is composed of a copolymer containing less than 50% by weight of the compound of general formula () and more than 50% by weight of the compound of general formula (), the strength of the membrane decreases, Not only does the encapsulation rate of the plasticizer in the powder plasticizer decrease, but also the mixing and heating operations for manufacturing the vinyl chloride resin composition and molding using the composition reduce the powder. The membrane constituting the composition is destroyed and the plasticizer inside is leached out, making mixing of the composition impossible. In the end, the polymer membrane forming resin according to the present invention is
It has the above copolymerization composition (2), that is, it is obtained by copolymerizing 50 to 99% by weight of the monomer of general formula () and 50 to 1% by weight of the monomer of general formula (). In this case, the tensile strength of the molded product finally obtained by molding the vinyl chloride resin composition of the present invention is such that it can ensure the practicality of the molded product. Furthermore, in the copolymerization constituting the polymer film forming resin, in addition to 100 parts by weight of the monomers of general formulas () and (), 10 to 1 part by weight of a compound of the group of monomers () mentioned above is mixed. When the resin thus obtained is used to produce the powdery plasticizer according to the present invention, the tensile strength of a molded article using the composition of the present invention using this plasticizer is improved. The reason for the improvement is thought to be the heating operation in the molding process and the accompanying crosslinking reaction. Even if the mixing ratio of the monomer () during the copolymerization described above exceeds 10%, there is no particular improvement in the effect, and if it is less than 1% by weight, the aforementioned effect of improving the tensile strength is lost. The composition of the powdered plasticizer coated with the polymer film according to the present invention is preferably such that the resin 5 forming the film is
~30% by weight and a plasticizer coated by the membrane95
Consisting of ~70% by weight. If the plasticizer content exceeds 95% by weight, the thickness of the coating will become relatively thin and the strength to retain the plasticizer will decrease. The coating may be torn and the plasticizer inside may leak out. On the other hand, when the plasticizer content is less than 70% by weight, the powdered plasticizer film becomes relatively thick, making it difficult to use in the mixing process for producing the composition of the present invention or the subsequent kneading process for producing molded articles. , the affinity and dispersibility of the powdered plasticizer according to the present invention with other parts of the composition (vinyl chloride resin + plasticizer) will be poor. After molding, the powdered plasticizer portion tends to form spots in the molded product. This is undesirable because it impairs the appearance of the molded product, that is, its commercial value. C. The powdery plasticizer according to the present invention can be produced by the method described in the Examples below. The type of plasticizer that is a component of the composition of the present invention is not particularly limited as long as it can be used in ordinary vinyl chloride resin compositions. For example, phthalic acid plasticizers such as dioctyl phthalate and dibutyl phthalate, trimellitic acid plasticizers such as tributyl trimellitic acid, aliphatic monobasic acid ester plasticizers such as octyl laurate, and dioctyl adipate. Aliphatic dibasic acid ester plasticizers, aromatic alcohol ester plasticizers, bidroxy acid ester plasticizers, coal tar distillate plasticizers, epoxy plasticizers, phosphate esters and polyester plasticizers, etc. They can be used alone or in combination of two or more, if necessary. The amount of such plasticizer blended in the ultra-soft vinyl chloride resin composition of the present invention is 50 to 50 parts by weight when directly blended with 100 parts by weight of vinyl chloride resin.
200 parts by weight The plasticizer contained in the powdered plasticizer coated with the polymer film is 35 to 190 parts by weight.
If the directly blended component is less than 50 parts by weight, soft blending will be difficult, and if it exceeds 200 parts by weight, the excess plasticizer will be leached from the composition. On the other hand, if the plasticizer content of the powdered plasticizer is less than 35 parts by weight, it is impossible to produce the extremely soft composition of the present invention, and if the amount exceeds 190 parts by weight, the resulting extremely soft composition cannot be used. The tensile strength and other strengths of the molded article are significantly reduced, and the molded article loses its practicality. Other additives that are incorporated into known vinyl chloride resin compositions can also be incorporated into the composition of the present invention without any problem. They are, for example, stabilizers, fillers,
Colorants, antioxidants, antistatic agents, flame retardants, lubricants, etc. The main raw materials for producing the composition of the present invention, that is, vinyl chloride resin, plasticizer, and powdered plasticizer coated with a polymer film, are mixed with other additives using a known mixer such as a high-speed mixer, ribbon blender, etc. The composition of the present invention can be easily obtained by mixing the above components. The composition of the present invention can be molded using a known molding machine, such as a general molding method such as a calendar, extrusion, blowing, pressing, or injection. The present invention will be explained below with reference to Examples and Comparative Examples. However, the present invention is not limited thereto. In addition, physical property tests of the compositions and molded articles in Examples and Comparative Examples were conducted by the following methods. ○B Blendability: Add 5 kg of vinyl chloride resin, plasticizer and other specified amounts of additives to a 75-capacity Healthiel mixer (trade name), and heat at 140℃ while mixing.
The mixture was heated to 70° C., then cooled to 70° C., and visually determined whether a homogeneous mixture could be removed from the mixer. (Judgment) ◎: Very easy to take out ○: Can be taken out △: Slightly difficult to take out ×: Slightly difficult to take out ××: Not possible to take out ○B Tensile strength and elongation: Conformed to Jis K-6301. ○Hub: The composition was heated _to 100°C at 65mmExt.
C ₂ 120℃, D 130℃ Pelletize 1 screen Me′ at 40 rpm, pelletize at 40m/mExt C ₁ 110
℃, _C2 120℃, _C3 130℃, D140℃ 1×20m/
A belt of m was molded and the spots on the surface were evaluated. (Judgment Criteria) ◎ No spots × Many spots 〇 There are spots ×× Extremely many spots △ Some spots Example 1 A Preparation of the powdered plasticizer according to the present invention; Methyl meth in the amount shown in Table 1 below In addition to the acrylate and vinylidene chloride, 15 g of diisopurperoxydicarbonate and 2800 g of dioctyl phthalate were mixed to prepare an oil phase composition. Next, 2800 g of deionized water, 1390 g of colloidal silica dispersion (solid content 20%), potassium dichromate
A composition for the aqueous phase was prepared by mixing 30 g of a 2.5% aqueous solution and 90 g of a 10% aqueous solution of a condensate of diethanolamine and adipic acid and adjusting the pH to 4 using hydrochloric acid. Next, both compositions were placed in a high-speed stirring tank.
A mixed solution was prepared by mixing at 10,000 rpm for 60 seconds.
The total volume of this mixture was previously purged with nitrogen to a volume of 15
Pressure polymerization reactor with an internal pressure of 3.5 to 4.5 kg/
The reaction was carried out at cm ² G and 50° C. for 20 hours. The reaction mixture was then cooled and depressurized, and the solid content contained therein was repeatedly centrifuged and washed with water (at 50°C under reduced pressure), and then dried to give an average particle size of 15.
3400 g of a white powder of ~30μ (note: powdered plasticizer coated with a polymer film according to the invention) was obtained. The inclusion rate of dioctyl phthalate was 82%. B. Preparation of vinyl chloride resin composition; 5 kg of vinyl chloride resin with an average degree of polymerization of 2900, Ca
-0.1Kg of Zn-based stabilizer, 1Kg of calcium carbonate, and the total amount of the above white powder (Note: When converted to the amount of raw material monomer, the amount is shown in Table 1 below) to a capacity of 75
The mixture was put into a high-speed stirring mixer (Note, trade name: Hersiel Mixer). Add the contents to 120 ml while stirring.
Raise the temperature to ℃ and add 10 kg of dioctyl phthalate.
Additionally added and heated to 140℃, mixed and then 70℃
The resultant mixture was cooled to a temperature of 100.degree. C. to obtain an extremely soft vinyl chloride resin composition according to the present invention. This composition was formed into a sheet using two 6-inch diameter rolls maintained at 130°C, and the sheet was pressed at 180°C (note: a 36Ton press was used) to prepare test pieces for each measurement purpose. It was created. Table 1 shows the results of measurements made on these test pieces. Comparative Example 1 The same procedure as in Example 1 was carried out, except that instead of the combination of methyl methacrylate and vinylidene chloride used in Example 1, A, the entire amount was changed to methyl methacrylate to obtain a white powder (Comparative Example 1 −
1). Further, the same procedure as in Example 1 was carried out except that 2788 g of DOP was used instead of this white powder. (Comparative Example 1-2). The results of these measurements are shown in Table 1.

[Table] As is clear from Table 1, when the white powder according to the present invention, that is, the plasticizer coated with a polymer film is not used (Comparative Example 1-2), the blendability of the vinyl chloride resin composition is It was extremely poor and impossible to extract (from the Herschel mixer in its original formulation). Furthermore, although not shown in the table, as a result of testing the blooming properties of the compositions, no blooming was observed in any of the compositions of the examples, while on the other hand, compositions containing only a plasticizer and no white powder were tested. What was used (Comparative Example 1-2)
A large amount of blooming was observed. From the above results, it is clear that the effect of blending the white powder according to the present invention, that is, the plasticizer coated with a polymer film, in the ultra-soft vinyl chloride resin composition of the present invention is clear. Example 2 A Preparation of powder plasticizer according to the present invention; Example 1 except that methyl methacrylate, vinylidene chloride and 5-ethylidene-2-norbornene were used in the amounts shown in Table 2 below.
- A white powder was obtained in the same manner as in A. (b) Preparation of the vinyl chloride resin composition; except for using the white powder obtained in (a) above,
It was carried out in the same manner as in Example 1-b. The results are shown in Table 2. As is clear from a comparison between the same table and the results of Examples 1-3 in Table 1, in preparing the powder plasticizer, in addition to methyl methacrylate and vinylidene chloride, a relatively small amount of 5-ethylidene-
It can be seen that when an appropriate amount of 2-norbornene is added, the tensile strength of the final molded product is significantly improved.

[Table] Note: 630g of methyl methacrylate and vinylidene chloride as co-raw material monomers for each No.
and 70g were used.

Claims (1)

[Scope of Claims] 1. 100 parts by weight of vinyl chloride resin, 50 to 200 parts by weight of a plasticizer, and 50 to 99% by weight of monomers of the following general formula () and monomers of the general formula () as a resin for forming a polymer film. A powdery plasticizer coated with a polymer film made of a copolymer obtained by copolymerizing 50 to 1% by weight of 50% to 1% by weight of a polymer. 50 to 30% by weight of a molecular film-forming resin and 95 to 70% by weight of a plasticizer coated by the film.
An ultra-soft vinyl chloride resin composition consisting of 200 parts by weight. General formula () CH ₂ = CX−COOR However, X is H, CH ₃ , R is H, CH ₃ −(CH ₂ −
CH ₂ −) _o H, where n = 1 to 18 General formula () [Formula] However, X is H, Cl, and Y is Cl 2 The above general formula () as a resin for forming a polymer film
50 to 99% by weight of monomers and 50 to 1% by weight of monomers of general formula (), total 100% by weight, and () as 1,4-hexazine, 2-methyl-1,4-
Pentadiene, cyclopentadiene, 1,5-cyclooctadiene, 4,7,8,9-tetraviroindene, 1,2,4-trivinylcyclohexane, 5-methylene-2-norbornene, 5-butene-2-norbornene , using a multicomponent copolymer obtained by copolymerizing one or more monomers selected from 5-ethylidene-2-norbornene in an amount of 0 to 10% by weight based on the total amount of () and (). The composition according to claim 1.