JPH08302129A - Vinyl chloride resin composition - Google Patents

Abstract

PURPOSE: To obtain a vinyl chloride resin composition which shows good moldability and shapability even when it contains a large amount of a woody powder and can give a molding more closely resembling wood in properties by mixing specified components with each other. CONSTITUTION: This vinyl chloride resin composition comprises 100 pts.wt. vinyl chloride resin (A), 40-175 pts.wt. woody powder (B), and 0.2-20 pts.wt. at least one compound (C) having a molecular structure represented by formula I or II (wherein R<1> and R<2> are each a (hydroxyl-substituted) alkyl group; and m is 1-10), the formula III or IV (wherein R<3> to R<5> are each a (hydroxyl- substituted) alkyl or phenyl group) or the formula V (wherein R<6> is a (hydoxyl- substituted) alkyl group; R<7> is a (methyl-substituted) phenyl group; and n is 0-6), and a vinyl chloride resin composition comprising 100 pts.wt. component A, 40-175 pts.wt. component B, 0.3-5 pts.wt. thermally decomposable blowing agent and 0.2-20 pts.wt. component C and/or 10-40 pts.wt. (meth)acrylic resin of a weight-average molecular weight of 2,500,000-6,000,000.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a vinyl chloride resin composition.

[0002]

2. Description of the Related Art In recent years, various attempts have been made to use synthetic resin compositions as substitute materials for wood by imparting properties close to those of natural wood. As one of the methods, there is a method of adding a powdery woody material to a synthetic resin.
It is known that the addition of such a wood material can efficiently impart the properties of the wood material to the original properties of the synthetic resin. In particular, in order to get a feel and lightness similar to wood,
It is more effective to use a vinyl chloride resin as a resin to form a foam and add a large amount of wood material. Currently, as a vinyl chloride resin molded product containing wood material, resin 10
A foamed molded product containing 20 to 30 parts by weight of a wood-based material with respect to 0 parts by weight is used as a home interior material such as a skirting board.

Due to the above resin molded product, characteristics close to those of wood, such as low coefficient of thermal expansion, nailability (characteristics for holding nails),
In order to impart texture such as heat resistance, rigidity and touch, it was necessary to incorporate a large amount of wood material.

However, if the content of the wood-based material in the resin molded product is increased, some problems occur in terms of both moldability and quality. As one of them, it is mentioned that the resin pressure at the time of molding becomes large and the flow of the resin in the mold becomes uneven. It is considered that these are caused by the fact that the resin essentially contains a large amount of wood-based material, so that the flow of the resin composition during melting becomes poor. As a result, "roughness" occurs on the surface of the molded product, "gloss" is lost, a dent occurs in the center of the molded product, so-called "sink" occurs, or the corners of the molded product are rounded. As a result, the surface or shape of the molded product is impaired.

Regarding the composition for molding a foam of a vinyl chloride resin containing wood powder, for example, Japanese Patent Publication No. 63-9.
Japanese Patent No. 540 discloses a method of improving the surface property of a molded article by blending an acrylic processing aid and a thermally decomposable organic or inorganic foaming agent. However, this method is effective when the amount of the wood powder is small, but when the amount of the wood powder is 30 parts by weight or more relative to 100 parts by weight of the vinyl chloride resin, the moldability and shapeability are improved. However, there was a problem that

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks, and an object thereof is to have good moldability and shapeability even when a large amount of wood powder is blended. , A vinyl chloride-based material that can give the resulting molded article properties that are closer to those of wood, such as a low coefficient of thermal expansion, nailability (property to hold nails), heat resistance, rigidity, texture such as touch, and surface condition. It is to provide a resin composition.

[0007]

The vinyl chloride resin composition of the first invention comprises a vinyl chloride resin, wood powder and a specific compound.

As the above-mentioned vinyl chloride resin, those conventionally known can be used. For example, a homopolymer of vinyl chloride, a copolymer of vinyl chloride and a polymerizable monomer other than vinyl chloride can be used. Polymers, graft copolymers obtained by grafting vinyl chloride onto polymers other than vinyl chloride; chlorinated vinyl chloride resins obtained by post-chlorinating these (co) polymers by a conventionally known method; ) A mixture of a polymer and a chlorinated vinyl chloride resin can be mentioned.

The polymerizable monomer other than vinyl chloride is not particularly limited as long as it has a reactive double bond, and for example, α-such as ethylene, propylene and butylene.
Olefin; Vinyl acetates such as vinyl acetate and vinyl propionate; Vinyl ethers such as butyl vinyl ether and cetyl vinyl ether; Methyl acrylate
Acrylic acid esters such as ethyl acrylate; Methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, phenyl methacrylate; styrene, α
-Aromatic vinyls such as methylstyrene; vinyl halides such as vinylidene chloride and vinyl fluoride; N- such as N-phenylmaleimide and N-cyclohexylmaleimide
Examples thereof include substituted maleimides, and these may be used alone or in combination of two or more kinds.

The polymer other than vinyl chloride used in the graft copolymer is not particularly limited, and examples thereof include ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-carbon monoxide copolymer, ethylene. -Ethyl acrylate copolymer, ethylene-propylene copolymer, acrylonitrile-butadiene copolymer, polyurethane resin,
Examples thereof include chlorinated polyethylene resin and chlorinated polypropylene resin, and these may be used alone or in combination of two or more kinds.

When the average degree of polymerization of the above vinyl chloride resin is small, the mechanical strength of the obtained molded product is insufficient, and when it is large, the melt viscosity at the time of molding becomes high and molding becomes difficult. 000 is preferable, and 400-1,000 is more preferable especially when foam molding is performed.

The above wood powder includes natural wood, rice husk,
Examples thereof include those made of natural cellulose fibers such as pulp, which have been atomized by a known method.Examples of natural wood include, for example, cedar, stalks, cypress, pine, lauan, and teak, which are generally used as wood. Those are preferably used.

The average particle size and the maximum particle size of the wood powder are
If it becomes large, it may stay inside the molding machine and cause “clog” or “burn”. Therefore, the average particle diameter is preferably 200 μm or less, more preferably 150 μm or less.
The maximum particle size is preferably 600 μm or less.

If the water content of the above wood powder increases, moisture foams during molding to roughen the surface of the molded body or accelerate deterioration of the resin during molding, so that the water content is preferably 10% by weight or less.

In the vinyl chloride resin composition, if the amount of the wood powder used is small, the feel and texture close to that of natural wood cannot be obtained, and if the amount is large, the melt viscosity of the resin increases and molding becomes difficult. It is limited to 40 to 175 parts by weight with respect to 100 parts by weight of the vinyl chloride resin.

The specific compound used in the present invention is represented by the following general formulas (a) to (e). The composition of the present invention contains at least one of the specific compounds represented by the general formulas (a) to (e).

(A) (R ¹ -CONH) ₂ (CH ₂ ) _m (b) (R ² -NHCO) ₂ (CH ₂ ) _{m In} formulas (a) and (b), R ¹ and R ² are An alkyl group or an alkyl group in which any hydrogen thereof is substituted with a hydroxyl group is shown, and m is an integer of 1-10.

(C) R ³ --NHCONH--R ⁴ (d) (R ⁵ --NHCONH) ₂ (CH ₂ ) _{m In} formulas (c) and (d), R ³ , R ⁴ and R ⁵ are alkyl groups. Alternatively, it represents an alkyl group or a phenyl group in which any hydrogen thereof is substituted with a hydroxyl group, and m represents an integer of 1 to 10.

(E) R ⁶ --NHCONH-(CH ₂ ) _n --R
_{^{7 - (CH 2) n -NHCONH}} -R 6 formula in (e), R ⁶ is an alkyl group or an alkyl group in which arbitrary hydrogen thereof is substituted with a hydroxyl group, R ⁷ is phenylene or any hydrogen Represents a phenyl group substituted with a methyl group, and n represents an integer of 0 to 6.

In the above general formulas (a) to (e), when m is large, the melting point of the specific compound becomes high, and it becomes difficult to uniformly mix it with the vinyl chloride resin, so that it is limited to 1 to 10. Also, for n, 0 to 6 for the same reason.
Limited to.

Further, the melting point of the above-mentioned specific compound is limited to 90 to 170 ° C., since the effect of improving sink marks cannot be exhibited even if the melting point is lowered or raised.

The above-mentioned specific compounds include methylenebisstearic acid amide, ethylenebiscapric acid amide,
Ethylenebislauric acid amide, ethylenebisstearic acid amide, ethylenebisisostearic acid amide, ethylenebis-1,2-hydroxystearic acid amide,
Bisamide compounds such as ethylene bis-behenic acid amide, hexamethylene bis-stearic acid amide, hexamethylene bis-1,2-hydroxystearic acid amide and hexamethylene bis-behenic acid amide; N, N'-distearyl succinic acid amide, N , N'-Distearyl adipic acid amide, N, N'-Distearyl sebacic acid amide and the like dialkylcarboxylic acid amide compounds; N-butyl-N'-lauryl urea, N-butyl-N'-stearyl urea, N -Phenyl-N'-stearylurea, N-stearyl-N'-stearylurea, N-stearyl-N'-behenylurea, ethylenebisstearylurea, hexamethylenebisstearylurea, hexamethylenebisbehenylurea and other urea derivatives Is mentioned.

In the vinyl chloride resin composition, when the amount of the above-mentioned specific compound used is small, the effect of improving moldability and shapeability is not sufficiently exhibited, and when the amount is too large, the slipperiness becomes too high during molding. Since the moldability is deteriorated and the surface condition and mechanical strength are deteriorated, the above vinyl chloride resin 10
It is limited to 0.2 to 20 parts by weight, preferably 0.5 to 8 parts by weight, relative to 0 parts by weight.

Next, the second invention will be described. The vinyl chloride resin composition of the second invention comprises a vinyl chloride resin, wood powder, a thermal decomposition type foaming agent, a specific compound and / or a (meth) acrylic resin.

As the vinyl chloride resin and the wood powder used in the second invention, those similar to the first invention are used.

In the vinyl chloride resin composition, the amount of wood powder used is limited to 40 to 175 parts by weight based on 100 parts by weight of the vinyl chloride resin for the same reason as in the first invention.

The thermal decomposition type foaming agent used in the second invention is not particularly limited as long as it is thermally decomposed during melt molding to generate a gas, and either an organic foaming agent or an inorganic foaming agent is used. Although usable, it is preferable to use an organic foaming agent capable of forming a denser foam cell in order to obtain a feel and a texture closer to that of wood. Examples of the organic foaming agent include azodicarbonamide, dinitrosopentamethylenetetramine, p, p′-oxybis (benzenesulfonylhydrazide) and the like.

In the above vinyl chloride resin composition, if the amount of the thermal decomposition type foaming agent used is small, the amount of gas generated is small, so that foaming is insufficient and uniform cells cannot be obtained. It may be torn or stick to each other and become non-uniform, and the appearance of the molded product may be impaired and surface coloring may occur. Therefore, it is limited to 0.3 to 5 parts by weight with respect to 100 parts by weight of the vinyl chloride resin, and preferably 0.3 ~
2 parts by weight.

As the above specific compound, the same compounds as in the first invention are used.

In the vinyl chloride resin composition, the amount of the specific compound used is 0.2 to 2 with respect to 100 parts by weight of the vinyl chloride resin for the same reason as in the first invention.
It is limited to 0 parts by weight, preferably 0.5 to 8 parts by weight.

Examples of the (meth) acrylic resin include homopolymers of (meth) acrylate monomers such as methyl (meth) acrylate, ethyl (meth) acrylate and butyl (meth) acrylate; Two or more selected copolymers; the (meth)
Examples thereof include a copolymer of an acrylate monomer and a vinyl monomer such as styrene, vinyltoluene and acrylonitrile.

When the weight average molecular weight of the (meth) acrylic resin is small, the foamed cells are melted at the time of forming the foamed cells and the foamed cells are broken, and foaming does not occur up to a predetermined expansion ratio. Or the
Since there is a risk of damaging the molding machine, 2.5 to 6 million
Limited to one million.

In the vinyl chloride resin composition, when the amount of the (meth) acrylic resin used is small, the effects of stabilizing the foam cells, improving the flowability of the resin and improving the surface condition of the molded article are sufficiently exhibited. However, if the amount is too large, the viscosity of the resin at the time of melting becomes high, the moldability is lowered, and the flame retardance, mechanical strength, water resistance and the like are lowered, so that it is 10 to 100 parts by weight of the vinyl chloride resin. Limited to 40 parts by weight.

To the vinyl chloride resin composition of the present invention, compounding agents such as stabilizers, stabilizing aids, lubricants, processing aids, foaming aids, fillers, plasticizers, release agents and pigments are added. May be done.

Examples of the stabilizer include lead white, basic lead sulfite, dibasic lead sulfite, tribasic lead sulfate, dibasic lead phosphite, silica gel co-precipitated lead silicate, lead stearate, benzoin. Lead-based compounds such as lead acidate, dibasic lead stearate and lead naphthenate; metal soaps such as calcium stearate, barium stearate and zinc stearate; dibutyltin malate, dibutyltin laurate, dioctyltin malate, dioctyltin laurate. And other tin-based compounds. Incidentally, the combined use of a compound having a mercapto group and a lead-based compound is not preferable because they react with each other to produce lead sulfide and contaminate the molded body.

Examples of the lubricant include fatty acids such as stearic acid, fatty acid esters, olefin wax, and the like, and examples of the processing aid include acrylic resin (methyl methacrylate / butyl acrylate copolymer, etc.). ) Is mentioned. Examples of the filler include calcium carbonate and talc, and examples of the plasticizer include aromatic esters such as dioctyl phthalate.

Regarding the order and method of adding the above-mentioned compounding agents,
Any operation is possible, for example, some ingredients may be premixed with the wood powder, if desired.

In the production process of the vinyl chloride resin composition of the present invention, an apparatus used for mixing each component is
A generally known mixing device can be used, for example, a general mixer having a structure in which stirring blades such as a flat plate type, a propeller type, and a Fowler type are rotated in a mixing tank; a ball mill having a structure in which stirring balls are made to flow in the mixing tank. A crusher; a shaker, etc., but in terms of manufacturing efficiency and workability,
A Henschel mixer having a stirring blade capable of rotating at high speed in the mixing tank is preferable.

For molding the above vinyl chloride resin composition,
A known molding method is used, and when molding by an extrusion molding method, a single-screw extruder, a twin-screw extruder or the like is preferably used as the extruder. In the case of extrusion molding, in order to improve the quality and work efficiency of the molded product, the pellets may be once pelletized and then extrusion molded. Molding temperature is 1 cylinder temperature
The temperature is preferably 10 to 190 ° C, and the mold temperature is preferably 130 to 190 ° C.

[0040]

Embodiments of the present invention will be described below. (Examples 1 to 11, Comparative Examples 1 to 8) Predetermined amounts of vinyl chloride resin (polymerization degree 800), wood powder and specific compound shown in Tables 1 and 2, lead stearate 4 parts by weight, steer 2 parts by weight of calcium phosphate, 10 parts by weight of methyl methacrylate / butyl acrylate copolymer and a predetermined amount of the foaming agent shown in Table 1 were added to a super mixer (100
Liter, manufactured by Kawada Kogyo Co., Ltd.), and 30 at 40-80 ° C
The mixture was kneaded for a minute to obtain a vinyl chloride resin composition.

[0041]

[Table 1]

[0042]

[Table 2]

The following were used as the wood powder, the specific compound and the foaming agent.・ Wood powder: Water content of 5 which was obtained by drying and crushing shavings for building materials.
Weight%, average particle size 60 μm (maximum particle size 300 μm).・ Specific compound: (1) Ethylenebisstearic acid amide (in the table, EBSA
(2) Ethylenebisoleic acid amide (shown as EBOA in the table) (3) Ethylenebisolein-1,2-hydroxystearic acid amide (shown as EBHSA in the table) (4) N, N'- Distearyl sebacic acid amide (D in the table
(Displayed as SSA) (5) Ethylene bis-stearyl urea (displayed as EBSU in the table) -Blowing agent: azodicarbonamide ("Vinihol AC # 1" manufactured by Eiwa Chemical Co., Ltd.)

The above vinyl chloride resin composition was fed to a 50 mm twin-axis different-direction oblique-axis extruder ("SLM50" manufactured by Nagata Seisakusho) and pelletized under the following molding conditions. [Molding conditions] 1) Screw rotation speed: 20 rpm 2) Molding temperature: 100 to 130 ° C. (barrel part), 140
C. (Mold part) 3) Cutting method: hot cutting Next, the pellets obtained above were processed into a single-screw extruder with the following specifications ("GT-32-A" manufactured by Plastic Engineering Laboratory Co., Ltd.).
The parison discharged from the mold lip using a cooling tank equipped with a sizing die and a take-up machine, and then passed through a sizing die cooled with water, and then cooled in a cooling tank filled with water. Then, a (foamed) molded body was obtained. [Extruder specifications] 1) Cylinder: Diameter 30 mm 2) Screw: L / D = 28 3) Mold: T die, lip: Width 33 x thickness 5 mm [Molding conditions] Molding temperature: 100-180 ° C (barrel part) ), 170 ℃
(Mold part) [Cooling tank] 1) Sizing die Lip: Width 40 x thickness 8 mm (Examples 1-9, Comparative Examples 1-5) (Examples 12-22, Comparative Examples 9-20) Lip: Width 33 × thickness 5 mm (Examples 10 and 11, Comparative Examples 6 to 8) 2) Cooling tank: length 1 mm, water volume 30 liters, water temperature 1
9 to 21 ° C [Take-off machine] Take-off speed: 60 cm / min

With respect to the foamed molded product obtained above, the extrusion moldability was evaluated from the following moldability, surface properties and shaping properties, and the results are shown in Tables 3 and 4. (A) Moldability The pressure of the molten resin in the barrel head of the extruder when molding pellets was measured. Molds with high pressure were considered to have poor moldability. (B) Surface property The following three points of "coloring", "smoothness" and "luster" were evaluated. The "coloring" of the surface of the obtained molded product was judged according to the following criteria. ⊚: White to ocher color similar to that of the resin composition stage ∘: Ocher color Δ: Light brown x: Brown to black color ・ The "smoothness" of the surface of the obtained molded product was judged according to the following criteria. ◯: Smooth and moderate wood texture Δ: Smooth plastic feel x: Rough feeling ・ Gloss The "gloss" of the surface of the obtained molded product was judged according to the following criteria. ◯: There is gloss x: There is no gloss (c) Formability It was evaluated from the following “sink marks” and “shape of corners”. -Sink: The distance between the upper and lower surfaces of the molded product was measured, and the ratio with the lip thickness of the sizing die was calculated by the following formula, and from this value, the "sink" was evaluated according to the following criteria. Distance between upper and lower surfaces (mm) / 8 (lip thickness of sizing die) (Examples 1 to 9 and Comparative Examples 1 to 5) (Examples 12 to 22 and Comparative Examples 9 to 20) Distance between upper and lower surfaces ( mm) / 5 (lip thickness of sizing die) (Examples 10 and 11 and Comparative Examples 6 to 8) ○: 0.95 or more Δ: 0.8 to less than 0.95 ×: less than 0.8 ・ Corner The shape of the corner portion of the molded body having an angle of 90 degrees was evaluated according to the following criteria. ◯: Sharp corners are formed Δ: Slightly rounded ×: Clearly rounded

[0046]

[Table 3]

[0047]

[Table 4]

(Examples 12 to 22, Comparative Examples 9 to 20) A predetermined amount of vinyl chloride resin shown in Tables 5 and 6 (having a polymerization degree of 80) was used.
0), wood powder, (meth) acrylic resin and foaming agent were placed in a super mixer (100 liters, manufactured by Kawada Kogyo Co., Ltd.) and kneaded at 40 to 80 ° C. for 30 minutes to obtain a vinyl chloride resin composition.

[0049]

[Table 5]

[0050]

[Table 6]

In Tables 5 and 6, the following were used. -Lead-based compound: Lead stearate-Metal soap: Calcium stearate-Processing aid: Acrylic resin-Foaming agent: Azodicarbonamide-Methyl methacrylate-butyl acrylate copolymer Methyl methacrylate: Butyl acrylate = 70: 3
0 (weight ratio) Weight average molecular weight = 1.5 million, 3 million, 4.5 million, 58
0 million or 7 million

Example 1 was prepared from the above vinyl chloride resin composition.
Using the same extruder, sizing die and cooling bath as in Example 1, foam molding was performed under the same conditions as in Example 1. The foamed article obtained above was evaluated for "foamability", "shapeability" and "surface property", and the results are shown in Tables 7 and 8. (D) Foaming property The specific gravity of the foamed molded product was measured to evaluate the foaming property. When the specific gravity was less than 1.0, it was determined to have sufficient foamability. (E) Shapeability It was evaluated by the same method as in Example 1. (F) Surface property Evaluation was made in the same manner as in Example 1.

[0053]

[Table 7]

[0054]

[Table 8]

[0055]

The vinyl chloride resin composition of the present invention has the above-mentioned constitution and contains a specific compound which has an appropriate compatibility with the vinyl chloride resin and exhibits high fluidity at high temperature. By doing so, a certain flowability is maintained even when the wood powder is highly filled, and the moldability and the surface condition of the molded product can be improved. Further, since the above-mentioned specific compound has a high melting point, it is possible to improve the shapeability by accelerating the solidification of the resin at the time of shaping and quickly fixing the shaped shape. Furthermore, by containing the (meth) acrylic resin, it is possible to improve foamability and shapeability even when the wood powder is highly filled.

Claims (2)

[Claims] 1. A vinyl chloride resin of 100 parts by weight, a wood powder of 40 to 175 parts by weight, and the following general formulas (a) to (e).
A vinyl chloride-based resin having at least one kind of a molecular structure represented by and consisting of 0.2 to 20 parts by weight of at least one kind of a specific compound having a melting point of 90 to 170 ° C. Resin composition. (A) (R ¹ -CONH) ₂ (CH ₂ ) _m (b) (R ² -NHCO) ₂ (CH ₂ ) _m [In the formulas (a) and (b), R ¹ and R ² are alkyl groups. or shows its any alkyl group wherein a hydrogen has been substituted with a hydroxyl group, m is an integer of 1 to 10] ^{(c) R 3 -NHCONH-R} 4 (d) (R 5 -NHCONH) 2 (CH 2) _m [in the formulas (c) and (d), R ³ , R ⁴ and R ⁵ represent an alkyl group or an alkyl group in which any hydrogen thereof is substituted with a hydroxyl group or a phenyl group, and m is an integer of 1 to 10] shown] ^{(e) R 6 -NHCONH- (CH} 2) n -R 7 - (CH 2) n
During -NHCONH-R ⁶ [wherein (e), R ⁶ is an alkyl group or an alkyl group in which arbitrary hydrogen thereof is substituted with a hydroxyl group, R ⁷ is a phenylene group or an optionally hydrogens thereof are substituted with a methyl group A phenyl group, and n represents an integer of 0 to 6] 2. 100 parts by weight of vinyl chloride resin, 40 to 175 parts by weight of wood powder, 0.3 to 5 parts by weight of a thermal decomposition type foaming agent, and at least one kind of the specific compound of claim 1.
2 to 20 parts by weight and / or weight average molecular weight of 2.5 million to 6
A vinyl chloride resin composition comprising 10 to 40 parts by weight of a (meth) acrylic resin of, 000,000.