JP6995533B2 - Manufacturing method of polyvinyl chloride resin molded product - Google Patents

Description

The present invention relates to a method for producing a polyvinyl chloride resin molded product, which has a small frictional resistance and can obtain a molded product having a matte surface.

Resin molded products using polyvinyl chloride (PVC) have excellent chemical and physical properties such as chemical resistance, weather resistance, flame retardancy, and electrical insulation, and are inexpensive, so they can be used. It is widely used as a high-value general-purpose resin material. Since PVC resin can be easily softened or softened by adding a plasticizer, it is used in a wide range of applications such as covering materials, flooring materials, waterproof sheets, tapes, bags, hoses, and the like.

Conventional general resin molded products made of PVC do not have a favorable feel when touched by the skin such as hands and legs, and may feel sticky or sticky to the skin. In addition, since it has a luster peculiar to synthetic resin, it is not always preferable in terms of appearance, especially in situations where a high-class feeling is required. For example, a watering hose using soft PVC has a smooth and smooth surface morphology, but on the other hand, the hose surface has high adhesiveness and friction resistance, so when it is wound on a reel, the hoses come into close contact with each other. There was a problem that winding and pulling out could not be done smoothly.

Therefore, the surface morphology of the PVC resin molded product has been improved. For example, it has been proposed to add a partially crosslinked resin and a surface modifier to a polyvinyl chloride resin (Patent Document 1). According to Patent Document 1, a low friction surface is formed by extrusion-molding a vinyl chloride resin composition to which a partially crosslinked resin is added, and the frictional resistance of the surface of the resin molded product can be reduced. It has also been proposed to improve the stickiness of the surface of a vinyl chloride resin hose without using a partially crosslinked resin as in Patent Document 1 (Patent Document 2). According to Patent Document 2, a plurality of synthetic resins having different molecular weights are mixed and heat-molded at a temperature higher than the melting temperature of the low molecular weight resin and lower than the melting temperature of the high molecular weight resin to obtain a molded product. It is said that a synthetic resin hose with reduced frictional resistance can be obtained by forming fine irregularities (fish eyes) on the outer surface.

Japanese Unexamined Patent Publication No. 2001-248764 Japanese Patent No. 4187112

However, in the molded product described in Patent Document 2, in order to form a fish eye, it is necessary to perform molding at a melting temperature substantially higher than the melting temperature of the PVC resin used as a base, so that it is usual. In order to form a fish eye using an extruder of a molded product production line using PVC resin, it is necessary to change the temperature condition of the extruder. Therefore, when a normal PVC resin molded product and a fisheye-formed PVC resin molded product are alternately manufactured using an extruder on the same production line, the temperature of the extruder is increased each time. It is complicated because it needs to be adjusted. Further, since a high molecular weight PVC resin is used in addition to the usual PVC resin, the stability during molding may be impaired.

Therefore, according to the present invention, polyvinyl chloride resin molding can obtain a molded product having a matte surface by reducing the frictional resistance of the surface without changing the molding processing conditions such as the temperature of the extruder. It is to provide a method of manufacturing a product. Another object of the present invention is to provide a polyvinyl chloride resin molded product having a matte surface with reduced surface frictional resistance.

As a result of diligent research, the present inventor added a polyvinyl chloride resin together with the compound and extruded it when producing a polyvinyl chloride resin molded product using a compound in which a plasticizer was mixed with the polyvinyl chloride resin. It was found that the above-mentioned problems can be achieved by molding. The present invention is based on such findings.

That is, the method for producing a polyvinyl chloride resin molded product according to the present invention is
(A) Component (a) 100 parts by mass of the first vinyl chloride resin,
Component (b) Plasticizer 40 parts by mass or more, 100 parts by mass or less,
A step of preparing a vinyl chloride resin compound kneaded with the above, and (B) a step of adding a second vinyl chloride resin to the vinyl chloride resin compound and performing melt molding.
Including
The average degree of polymerization P2 of the second vinyl chloride resin is 0.5 times or more and 1.9 times or less the average degree of polymerization P1 of the first vinyl chloride resin.
The second vinyl chloride resin is blended in an amount of 1 part by mass or more and 8 parts by mass or less with respect to 100 parts by mass of the vinyl chloride resin compound.

The second invention is the manufacturing method according to the first invention, wherein the melt molding is performed at the melt molding temperature of the vinyl chloride resin compound.

The third invention is the production method according to the first or second invention, wherein the first vinyl chloride resin has an average degree of polymerization P1 of 500 or more and 3,000 or less.

A fourth invention is the production method according to any one of the first to third inventions, wherein the vinyl chloride resin compound further contains a stabilizer.

The fifth invention is the first to fourth inventions in which the average degree of polymerization P2 of the second vinyl chloride resin is 1.0 times or less the average degree of polymerization P1 of the first vinyl chloride resin. It is the manufacturing method described in any one of.

The vinyl chloride resin molded product of the sixth invention is
(A) Component (a) 100 parts by mass of the first vinyl chloride resin,
Component (b) Plasticizer 40 parts by mass or more, 100 parts by mass or less,
The vinyl chloride resin compound kneaded with the above, and (B) the second vinyl chloride resin,
It is a vinyl chloride resin molded product containing
The average degree of polymerization P2 of the second vinyl chloride resin is 1.0 times or less the average degree of polymerization P1 of the first vinyl chloride resin.
The second vinyl chloride resin is blended in an amount of 1 part by mass or more and 8 parts by mass or less with respect to 100 parts by mass of the vinyl chloride resin compound.

The seventh invention is the vinyl chloride resin molded product according to the sixth invention, wherein the ungelled product of the second vinyl chloride resin is dispersed on the surface.

According to the present invention, an extrusion molding machine is performed by adding a second vinyl chloride resin having a predetermined degree of polymerization to a vinyl chloride resin compound containing a first vinyl chloride resin and performing melt molding. To manufacture a vinyl chloride resin molded product having a matte (matte feeling) appearance with reduced surface friction resistance, slidability, without changing the molding processing conditions such as the temperature of the above. Can be done.

<Manufacturing method of vinyl chloride resin molded product>
The method for producing a vinyl chloride resin molded product according to the present invention includes a step of preparing a predetermined vinyl chloride resin compound and a melt molding by adding a second vinyl chloride resin to the prepared vinyl chloride resin compound. It includes steps. Hereinafter, each step will be described.

PVC resin compound preparation process:
In the method for producing a vinyl chloride resin molded product according to the present invention, a vinyl chloride resin compound is used. The vinyl chloride-based resin compound means a resin composition obtained by preliminarily adding an additive such as a plasticizer or a stabilizer to a vinyl chloride-based resin and kneading it. By preparing a vinyl chloride resin compound containing a predetermined amount of plasticizer, the obtained molded product becomes a soft vinyl chloride resin molded product.

Component used in the preparation of vinyl chloride resin compound (a) The first vinyl chloride resin means a polymer having a group represented by _-CH2 -CHCl-, and is only a polyvinyl chloride homopolymer. Not vinyl chloride / vinyl acetate copolymer, vinyl chloride / (meth) acrylic acid copolymer, vinyl chloride / methyl (meth) acrylate copolymer, vinyl chloride / ethyl (meth) acrylate copolymer, Vinyl chloride / maleic acid ester copolymer, vinyl chloride / ethylene copolymer, vinyl chloride / propylene copolymer, vinyl chloride / styrene copolymer, vinyl chloride / isobutylene copolymer, vinyl chloride / vinylidene chloride copolymer , Vinyl chloride / styrene / maleic anhydride ternary copolymer, vinyl chloride / styrene / acrylonitrile ternary copolymer, vinyl chloride / butadiene copolymer, vinyl chloride / isoprene copolymer, vinyl chloride / chlorinated propylene With vinyl chloride and other monomers copolymerizable with vinyl chloride, such as polymers, vinyl chloride / vinylidene chloride / vinyl acetate ternary copolymers, vinyl chloride / acrylonitrile copolymers, vinyl chloride / various vinyl ether copolymers, etc. Copolymer; A modified vinyl chloride homopolymer such as a post-chlorinated vinyl copolymer or a vinyl chloride-based copolymer; and a chlorinated polyolefin structurally similar to a vinyl chloride resin such as chlorinated polyethylene. Include. These vinyl chloride resins may be used alone or in combination of two or more.

Component (a) The average degree of polymerization P1 of the first vinyl chloride resin is preferably in the range of 300 or more and 5,000 or less, more preferably 500 or more and 3,000 or less, and 700 or more and 1 , 300 or less is more preferable. By setting the average degree of polymerization P1 to 300 or more, the mechanical properties of the obtained molded product become good. Further, by setting the average degree of polymerization to 5,000 or less, the gelling characteristics are improved. The average degree of polymerization is JIS K6721 using a resin obtained by dissolving a vinyl chloride resin in tetrahydrofuran (THF), removing insoluble components by filtration, and then drying and removing THF in the filtrate as a sample. It means a value measured according to the "vinyl chloride resin test method".

The method for producing the component (a) first vinyl chloride resin used in the present invention is not particularly limited, and those produced by various polymerization methods such as an emulsion polymerization method, a suspension polymerization method, and a bulk polymerization method shall be used. Can be done.

As the component (b) plasticity used in preparing the vinyl chloride resin compound, any suitable plasticizer can be used as long as it does not contradict the object of the present invention. As such a plasticizer, for example, a phthalate ester plasticizer or a non-phthalic acid-based plasticizer can be used. As the phthalate ester plasticizer, it is particularly preferable to use dioctyl phthalate (DOP).

Further, a non-phthalic acid-based plasticizer may be used in combination. Non-phthalic acid-based plasticizers include trimellitic acid-based compounds, phosphoric acid-based compounds, adiponic acid-based compounds, citric acid-based compounds, ether-based compounds, polyester-based compounds, soybean oil-based compounds, and cyclohexanedicarboxylate-based compounds. , Preferably at least one selected from terephthalic acid compounds, for example, trimellitic acid esters such as tristrimertic acid (2-ethylhexyl), triisononyl trimellitic acid; tri-phosphate (2-ethylhexyl), Phosphoric acid esters such as tricredyl phosphate and trixylenyl phosphate; adiponic acid esters such as adipic acid (2-ethylhexyl) and diisononyl adipate; citric acid esters such as tributyl acetylcitrate; ether compounds such as polypropylene glycol; Polyester-based compounds; Soybean oil-based compounds such as epoxidized soybean oil; dimethylcyclohexane-1,2-dicarboxylate, diethylcyclohexane-1,2-dicarboxylate, din-butylcyclohexane-1,2-dicarboxylate , Cyclohexane dicarboxylate compounds such as di-2-ethylhexylcyclohexane-1,2-dicarboxylate, diisononylcyclohexane-1,2-dicarboxylate, diisodecylcyclohexane-1,2-dicarboxylate; diterephthalic acid di- Examples thereof include terephthalic acid compounds such as 2-ethylhexyl. Of these, diisononylcyclohexane-1,2-dicarboxylate and di-2-ethylhexyl terephthalate are preferable in terms of safety to the human body. These can be used individually by 1 type, or can be used in combination of 2 or more types.

Ingredients for preparing a vinyl chloride resin compound (b) By adjusting the blending amount of the plasticizer according to the intended use of the molded product, for example, flexibility for curtain rods, watering, material delivery, etc. It can be used for various purposes such as hoses, automobile interior materials, coated electric wires, flooring materials, sheets such as waterproof sheets, and films such as tapes and agricultural materials.

The blending amount of the component (b) plasticity depends on the intended use of the molded product, but in the present invention, 40 parts by mass or more and 100 parts by mass with respect to 100 parts by mass of the first vinyl chloride resin. Mix in the following proportions. When the blending amount of the plasticizer is within the above range, a so-called soft vinyl chloride resin molded product having good flexibility can be obtained, and stickiness during the molding process can be suppressed. The preferable blending amount of the plasticizer is 45 parts by mass or more and 90 parts by mass or less, and more preferably 50 parts by mass or more and 80 parts by mass or less with respect to 100 parts by mass of the first vinyl chloride resin.

When preparing the vinyl chloride resin compound, components other than the above-mentioned components (a) and (b) may be contained. In the present invention, as long as the effects of the present invention are not impaired, various additives such as conventional stabilizers, fillers, flame retardants, lubricants, impact-resistant modifiers, etc. may be added as necessary according to the purpose. Can be added.

Stabilizers include, for example, lead-based stabilizers such as tribasic lead sulfate, dibasic lead phosphite, basic lead sulfite, and lead silicate, and metals such as potassium, magnesium, barium, zinc, cadmium, and lead. Metallic soap-based stabilizers derived from fatty acids such as 2-ethylhexanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, hydroxystearic acid, oleic acid, ricinolic acid, linoleic acid, behenic acid; alkyl Organic tin-based stabilizer having a group, an ester group, a fatty acid group, a maleic acid group, a sulfide-containing group, etc .; Ba-Zn-based, Ca-Zn-based, Ba-Ca-Sn-based, Ca-Mg-Sn Composite metal soap-based stabilizers such as system, Ca-Zn-Sn system, Pb-Sn system, Pb-Ba-Ca system; metal groups such as barium and zinc and 2-ethylhexanoic acid, isodecanoic acid, trialkylacetic acid and the like. Usually two kinds of organic acids such as branched fatty acids, unsaturated fatty acids such as oleic acid, lysynolic acid and linoleic acid, alicyclic acids such as naphthenic acid, coalic acid, benzoic acid, salicylic acid and aromatic acids such as their substituted derivatives. Metal salt-based stabilizers derived from the above; these stabilizers are dissolved in organic solvents such as petroleum-based hydrocarbons, alcohols, and glycerin derivatives, and further, hypophosphates, epoxy compounds, color-developing agents, transparency improvers, etc. Metal-based stabilizers such as metal salt liquid stabilizers containing stabilizing aids such as light stabilizers, antioxidants, bleed-out inhibitors, and lubricants, as well as epoxy resins and epoxys such as epoxidized fatty acid alkyl esters. Examples thereof include non-metal stabilizers such as compounds and organic phosphite esters, and these are used alone or in combination of two or more.

The amount of the stabilizer added is not particularly limited, but is preferably 1 to 15 parts by mass, more preferably 1 to 8 parts by mass with respect to 100 parts by mass of the first vinyl chloride resin of the component (a). When the amount is 1 part by mass or more, thermal decomposition during processing can be suppressed, and when the amount is 15 parts by mass or less, deterioration of the mechanical properties of the molded product can be prevented.

Fillers include talc, heavy calcium carbonate, precipitated calcium carbonate, carbonates such as collagen carbonate, aluminum hydroxide, magnesium hydroxide, titanium oxide, clay, mica, wollastonite, zeolite, silica, zinc oxide. In addition to inorganic fibers such as magnesium oxide, carbon black, graphite, glass beads, glass fibers, carbon fibers, and metal fibers, organic fibers such as polyamide can also be used, and these may be used alone or in combination of two or more. be able to.

The amount of the filler added is not particularly limited, but is preferably 1 to 150 parts by mass, more preferably 10 to 100 parts by mass, based on 100 parts by mass of the vinyl chloride resin. When the content is 1 part by mass or more, appropriate rigidity can be imparted to the molded product, and when the content is 150 parts by mass or less, deterioration of the flexibility of the molded product can be prevented.

As the flame retardant, for example, a metal hydroxide, a bromine compound, a triazine ring-containing compound, a zinc compound, a phosphorus compound, a halogen flame retardant, a silicone flame retardant, an intomescent flame retardant, an antimony oxide and the like can be used. .. These can be used alone or in combination of two or more.

The amount of the flame retardant added is not particularly limited, but is preferably 1 to 150 parts by mass, more preferably 10 to 100 parts by mass with respect to 100 parts by mass of the vinyl chloride resin. When the content is 1 part by mass or more, the flame retardancy of the molded product can be improved, and when the content is 150 parts by mass or less, the flexibility of the molded product can be prevented from being lowered.

Examples of the lubricant include pure hydrocarbon-based lubricants such as liquid paraffin, natural paraffin, microwax, synthetic paraffin, and low molecular weight polyethylene, halogenated hydrocarbon-based lubricants, higher fatty acids, fatty acid-based lubricants such as oxyfatty acids, fatty acid amides, and bis. Fatty acid amide-based lubricants such as fatty acid amides, lower alcohol esters of fatty acids, polyhydric alcohol esters of fatty acids such as glycerides, polyglycol esters of fatty acids, ester-based lubricants such as fatty alcohol esters of fatty acids (ester wax), and metal soaps. , Fatty acid, polyhydric alcohol, polyglycol, polyglycerol, fatty acid and partial ester of polyhydric alcohol, fatty acid and polyglycol, partial ester of polyglycerol, etc., and these are used alone or in combination of two or more. be able to.

The amount of the lubricant added is not particularly limited, but is preferably 0.1 to 15 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the vinyl chloride resin. When the content is 0.1 part by mass or more, the adhesion of the resin composition to the molding machine can be reduced, and when the content is 15 parts by mass or less, deterioration of workability can be prevented.

When a shock-resistant modifier is blended, for example, chlorinated polyethylene, polybutadiene, polyisoprene, polychloroprene, fluororubber, styrene-butadiene copolymer rubber, acrylonitrile-styrene-butadiene copolymer rubber, methyl methacrylate -Styline-butadiene copolymer rubber, acrylic core-shell type rubber such as acrylic acid ester-methacrylate copolymer, silicone-acrylic acid ester-methacrylate copolymer, silicone-acrylic acid ester-acrylonitrile-styrene Examples thereof include silicone-based core-shell type rubbers such as polymers. These impact resistance modifiers can be used alone or in combination of two or more.

The amount of the impact resistance modifier added is not particularly limited, but is preferably 1 to 20 parts by mass, more preferably 1 to 15 parts by mass with respect to 100 parts by mass of the vinyl chloride resin. When the content is 1 part by mass or more, the impact strength of the molded product can be improved, and when the content is 20 parts by mass or less, deterioration of the molded appearance can be prevented.

In addition, a mold release agent, a fluidity improver, a colorant, an antistatic agent, a surfactant, an anti-fog agent, an antibacterial agent, a foaming agent, etc. are also arbitrarily used according to the purpose as long as the effects of the present invention are not impaired. Can be blended.

The vinyl chloride resin compound blends each of the above components using equipment such as a Henshell mixer, V-type mixer, and ribbon blender, and uses equipment such as a Banbury mixer, single-screw extruder, twin-screw extruder, roll, and kneader. It can be obtained by kneading at a temperature of 140 to 180 ° C. using the product. The obtained vinyl chloride resin compound is preferably pelletized by using a pellet manufacturing apparatus or the like as appropriate.

Melt molding process:
In the method for producing a vinyl chloride resin molded product according to the present invention, a second vinyl chloride resin is added to the vinyl chloride resin compound prepared as described above, and a second vinyl chloride resin is melt-molded to obtain a molded product. .. In the method described in Japanese Patent No. 4187112 and the like described above, vinyl chloride resins having different molecular weights are mixed and melt-molded, whereas in the present invention, a vinyl chloride resin compound (that is, a plasticizer or the like) is used. It can be said that it is characterized in that a second vinyl chloride resin is added to the already blended resin composition) to perform melt molding.

Since the vinyl chloride resin compound containing the first vinyl chloride resin contains a predetermined amount of plasticizer, it is in a state in which a part of the vinyl chloride resin is pseudo-crosslinked. In the present invention, when the second vinyl chloride resin is added to the vinyl chloride resin compound to form a melt, the vinyl chloride resin compound and the second vinyl chloride resin are melt-kneaded. However, since the second vinyl chloride resin is molded in an unmelted state, the second vinyl chloride resin appears as an ungelled product on the surface of the molded product in the form of granules. As a result, the frictional resistance of the surface is reduced, and a molded product having a matte surface is obtained. That is, it is a completely different concept from the method described in Patent Document 2 in which a high molecular weight PVC resin is deposited on the surface as an unmelted substance.

As the second vinyl chloride resin to be added to the vinyl chloride resin compound, various substances listed in the column of the component (a) first vinyl chloride resin can be used. Further, the second vinyl chloride resin may be the same as or different from the first vinyl chloride resin of the component (a). However, in the present invention, the average degree of polymerization P2 of the second vinyl chloride resin needs to be 0.5 times or more and 1.9 times or less the average degree of polymerization P1 of the first vinyl chloride resin. .. When the average degree of polymerization P2 of the second vinyl chloride resin is less than 0.5 times the average degree of polymerization P1 of the first vinyl chloride resin, the surface of the molded product is an ungelled product of the second vinyl chloride resin. It becomes difficult to make the appearance of the resin, the frictional resistance is reduced, and it becomes difficult to obtain a molded product having a matte surface. On the other hand, when the average degree of polymerization P2 of the second vinyl chloride resin exceeds 1.9 times the average degree of polymerization P1 of the first vinyl chloride resin, the moldability deteriorates and a stable molded product can be obtained. Can be difficult. The preferred average degree of polymerization P2 of the second vinyl chloride resin is 1.0 times or less the average degree of polymerization P1 of the first vinyl chloride resin.

The amount of the second vinyl chloride resin added to the vinyl chloride resin compound shall be 1 part by mass or more and 8 parts by mass or less with respect to 100 parts by mass of the vinyl chloride resin compound. When the amount of the second vinyl chloride resin added is less than 1% by mass with respect to 100 parts by mass of the vinyl chloride resin compound, the amount of ungelled material that appears granularly on the surface of the molded product is small, and the frictional resistance is reduced. The matting effect is insufficient. On the other hand, if the amount of the second vinyl chloride resin added exceeds 8 parts by mass with respect to 100 parts by mass of the vinyl chloride resin compound, the moldability deteriorates and it becomes difficult to stably obtain a molded product. In some cases. The amount of the second vinyl chloride resin added is preferably 2 parts by mass or more and 7 parts by mass or less, and more preferably 3 parts by mass or more and 6 parts by mass or less with respect to 100 parts by mass of the vinyl chloride resin compound. ..

A conventionally known molding machine can be used for melt molding the vinyl chloride resin compound and the vinyl chloride resin compound. A molding method such as injection molding, extrusion molding, inflation molding, calender molding, blow molding or the like can be appropriately selected according to the intended use of the molded product. When performing the molding process, in addition to the vinyl chloride resin compound and the vinyl chloride resin compound, additives such as the above-mentioned plasticizer may be added as appropriate.

The temperature at the time of molding (molding processing temperature) is preferably the melt molding temperature of the vinyl chloride resin compound. For example, as described above, in a vinyl chloride resin compound containing PVC having an average degree of polymerization of about 1300 and a predetermined amount of plasticizer, the molding temperature is about 140 to 160 ° C. Also when performing melt molding by adding the vinyl chloride resin of 2, it is preferable to perform melt molding at a temperature of about 140 to 160 ° C. Therefore, in the present invention, a vinyl chloride resin molded product having a reduced surface frictional resistance, slidability, and a matte appearance without changing molding processing conditions such as the temperature of the extruder. Can be manufactured.

<Vinyl chloride resin molded product>
The vinyl chloride-based resin molded product obtained as described above has a form in which the ungelled product of the second vinyl chloride-based resin appears in the form of particles and is dispersed on the surface. Therefore, it is possible to realize a molded product having a reduced frictional resistance, slidability, and a matte appearance.

In particular, the average degree of polymerization is added to the vinyl chloride resin compound obtained by kneading 100 parts by mass of the component (a) first vinyl chloride resin and 40 parts by mass or more and 100 parts by mass or less of the plasticizer (b). The vinyl chloride resin molded product obtained by melt-molding by adding a second vinyl chloride resin having a P2 of 1.0 times or less the average degree of polymerization P1 of the first vinyl chloride resin has surface friction resistance. It is reduced, has slidability, has a matte appearance, and is excellent in moldability.

The vinyl chloride resin molded product of the present invention includes curtain rails, flexible hoses for watering and material delivery, automobile interior materials, coated electric wires, flooring materials, sheets such as waterproof sheets, tapes, and agricultural products. It can be used for various purposes such as films such as.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

Evaluation methods:
(1) Roughness of the surface of the molded product Each sheet molded under the extrusion molding conditions described later was visually evaluated by comparison with Comparative Example 1 and Comparative Example 2 used as controls. The evaluation criteria for surface roughness are as follows.
◯: Surface morphology equivalent to Comparative Example 1 Δ: Surface morphology intermediate between Comparative Example 1 and Comparative Example 2 ×: Surface morphology equivalent to Comparative Example 2

(2) Formability Sheets were prepared under extrusion molding conditions, and each obtained sheet was visually evaluated. The evaluation criteria for formability were as follows.
○: The edge of the sheet is not cut △: The edge of the sheet is slightly cut ×: The sheet is intermittently cut

Extrusion conditions:
Extrusion machine: LSE-20 (L / D = 20)
Screw: Full flight screw Screw rotation speed: 40 rpm
Plate: Breaker plate with mesh Molding temperature: C1 temperature 140 ° C, C2 temperature 150 ° C, C3 temperature 160 ° C, die temperature 160 ° C

Raw materials used:
-Vinyl chloride resin P-400 (average degree of polymerization 400, polyvinyl chloride, manufactured by Sekisui Chemical Co., Ltd.)
P-700 (average degree of polymerization 700, polyvinyl chloride, manufactured by Shin-Etsu Chemical Co., Ltd.)
P-800 (average degree of polymerization 800, polyvinyl chloride, manufactured by Shin-Etsu Chemical Co., Ltd.)
P-1050 (average degree of polymerization 1050, polyvinyl chloride, manufactured by Shin-Etsu Chemical Co., Ltd.)
P-1300 (average degree of polymerization 1300, polyvinyl chloride, manufactured by Shin-Etsu Chemical Co., Ltd.)
P-1700 (average degree of polymerization 1700, polyvinyl chloride, manufactured by Shin-Etsu Chemical Co., Ltd.)
P-2500 (average degree of polymerization 2500, polyvinyl chloride, manufactured by Shin-Etsu Chemical Co., Ltd.)
-Partially cross-linked vinyl chloride resin K13M (average polymerization degree 1100, gel fraction 57%, manufactured by Kaneka Corporation)
・ Plasticizer DOP (dioctyl phthalate)
O-130S (epoxidized soybean oil, manufactured by ADEKA CORPORATION)
-Stabilizer SP-2015 (Ca-Zn-based stabilizer, manufactured by ADEKA CORPORATION)

Comparative Example 1 and Comparative Example 2
Each component was kneaded at 160 ° C. with a kneader (Banbury mixer) according to the composition shown in Table 1 below to prepare a compound. The numerical values in the table represent parts by mass. Using each of the obtained compounds, a sheet was prepared under the above extrusion molding conditions.

Since Comparative Example 1 contains cross-linked PVC, granular irregularities are formed on the surface of the molded product, the surface friction is small, and the surface has a matte surface. On the other hand, since Comparative Example 2 does not contain cross-linked PVC, the surface of the molded product is glossy and the surface roughness is poor.

Examples 1-5, Comparative Examples 3 and 4
To the compound used in Comparative Example 2, PVC resins (P-400, P-700, P-800, P-1050, P-1300, P-1700, and P-2500) having each degree of polymerization were added according to the composition shown in Table 2. ) Was added and molded under the same extrusion molding conditions as described above to prepare a sheet. The surface roughness and moldability of each of the obtained sheets were evaluated. The results are shown in Table 2 below.

Examples 1 to 5 had better surface roughness and moldability as compared with Comparative Examples 1 and 2. Surprisingly, not only Example 5 to which a PVC resin having a higher degree of polymerization than the PVC resin contained in the compound was added, but also Example 1 to which a PVC resin having a degree of polymerization equivalent to or lower than that was added, was carried out. In Example 2, Example 3, and Example 4, both the surface roughness property and the moldability were good. On the other hand, in Comparative Example 3 in which a PVC resin having an average degree of polymerization 1.9 times or more higher than that of the PVC resin contained in the compound was added, the surface roughness was good, but the moldability was poor. Further, in Comparative Example 4 to which a PVC resin having an average degree of polymerization less than 0.5 times that of the PVC resin contained in the compound was added, the moldability was good, but the surface roughness was insufficient.

Examples 6-7 and Comparative Example 5
A sheet is prepared by adding 1 part by weight, 8 parts by weight and 10 parts by weight of PVC resin (P-1050) to the compound used in Comparative Example 2 and molding under the same extrusion molding conditions as described above. did. The surface roughness and moldability of each of the obtained sheets were evaluated. The results are shown in Table 3 below.

In Example 6, since the amount of PVC resin added to the compound is small, the surface roughness is slightly inferior to that of Example 3, and in Example 7, the amount of PVC resin added to the compound is large. While the moldability was slightly inferior to that of Example 3, Comparative Example 5 in which the amount of the PVC resin added was 10 parts by mass had good surface roughness, but poor moldability.

Claims (4)

(A) Component (a) 100 parts by mass of the first vinyl chloride resin,
Component (b) Plasticizer 40 parts by mass or more, 100 parts by mass or less,
A step of preparing a vinyl chloride resin compound kneaded with the above, and (B) a step of adding a second vinyl chloride resin to the vinyl chloride resin compound and performing melt molding.
Including
The average degree of polymerization P1 of the first vinyl chloride resin is 700 or more and 1,300 or less.
The average degree of polymerization P2 of the second vinyl chloride resin is 0.5 times or more and 1.9 times or less the average degree of polymerization P1 of the first vinyl chloride resin.
The blending amount of the second vinyl chloride resin is 1 part by mass or more and 8 parts by mass or less with respect to 100 parts by mass of the vinyl chloride resin compound.
The melt molding of (B) is carried out under the same conditions as the molding processing conditions in the case of melt molding using only a vinyl chloride resin compound.
The ungelled product of the second vinyl chloride resin is dispersed on the surface of the obtained molded product.
A method for producing a vinyl chloride resin molded product. The production method according to claim 1 , wherein the vinyl chloride resin compound further contains a stabilizer. The production method according to claim 1 or 2 , wherein the average degree of polymerization P2 of the second vinyl chloride resin is 1.0 times or less the average degree of polymerization P1 of the first vinyl chloride resin. (A) Component (a) 100 parts by mass of the first vinyl chloride resin,
Component (b) Plasticizer 40 parts by mass or more, 100 parts by mass or less,
The vinyl chloride resin compound kneaded with the above, and (B) the second vinyl chloride resin,
It is a vinyl chloride resin molded product containing
The average degree of polymerization P1 of the first vinyl chloride resin is 700 or more and 1,300 or less.
The average degree of polymerization P2 of the second vinyl chloride resin is 1.0 times or less the average degree of polymerization P1 of the first vinyl chloride resin.
The blending amount of the second vinyl chloride resin is 1 part by mass or more and 8 parts by mass or less with respect to 100 parts by mass of the vinyl chloride resin compound.
The ungelled material of the second vinyl chloride resin is dispersed on the surface.
A vinyl chloride resin molded product characterized by this.