JP2000336275A - Resin composition for profile extrusion molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition which does not cause fine splits on its molded item by blending a lignocellulose or cellulose material, a polyolefin resin, a specific amount of polytetrafluoroethylene and a specific amount of an alkyl (meth)acrylate polymer. SOLUTION: This resin composition contains 0.1-1.5 wt.% of polytetrafluoroethylene and 0.05-4.5 wt.% of an alkyl (meth)acrylate polymer. Preferably the resin composition contains not less than 20 wt.% of (A) a lignocellurose or cellulose material. Preferably the material (A) is (B) an esterified lignocellulose or cellulose material. Preferably the material (B) is a maleic acid-modified wood powder obtained by carrying out addition- esterification of a wood powder with maleic anhydride. A polyolefin to be used is preferably a mixture of a polypropylene of an MFR of 0.1-200 g/10 min at 230 deg.C and a polyethylene of an MFR of 0.01-200 g/10 min at 190 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyolefin resin composition containing a lignocellulosic or cellulosic substance typified by wood-based materials, and more particularly, to a corner portion ( Hereinafter, it is referred to as an edge.)
The present invention relates to a resin composition excellent in molding processability, in which "sagging" is prevented.

[0002]

2. Description of the Related Art Conventionally, it has been studied to mix wood-based materials with thermoplastic resins such as polyolefins.
However, when a hydrophilic wood-based material is directly blended with a hydrophobic polyolefin, the affinity of the wood-based material is low, so that the heat fluidity of the resin composition is reduced and the moldability is reduced. Has a problem that the mechanical strength is reduced.

[0003] As a method of solving such problems and improving the affinity between a wood-based material and a polyolefin,
For example, a method in which a modified polyolefin resin is added as a compatibilizer (Japanese Patent Application Laid-Open Nos.
167743) and a method of imparting affinity to a thermoplastic resin by subjecting a wood-based material to chemical treatment (Japanese Patent Publication No. 1-59302).

Further, when a polypropylene resin is used as the thermoplastic resin, an organic peroxide is blended to improve the thermal fluidity (Japanese Patent Publication Nos. 62-5186 and 1-22297). , Tokuho 5-6050
No. 2) has also been proposed. By these methods, it has become possible to some extent to mold and process a polyolefin-based resin composition containing a lignocellulosic or cellulosic substance represented by a wood-based material.

[0005] However, when the above resin composition is applied to a profile extrusion molding for producing a complex shape having the same cross-sectional shape, the melt tension of the polyolefin resin composition is insufficient. For this reason, when the radius (R) of the edge is small, there is a problem in that the resin is cut off at that portion and "scratch" is easily generated. Therefore, there has been no choice but to form a round bar having no edge by avoiding molding with a mold having a small edge radius (R) or a complicated mold, or to adopt a molding design having a large edge radius (R). Such a tendency was more remarkable as the content of the lignocellulosic or cellulosic material was higher.

[0006]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems and provides a profile extrusion without causing "scratching" at edges even when the content of lignocellulosic or cellulosic substances is high. An object of the present invention is to provide a polyolefin resin composition that can be molded.

[0007]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a composition comprising a lignocellulose-based or cellulosic substance (A) and a polyolefin-based resin (B) is further added with a specific proportion. The inventors have found that the above-mentioned problems can be solved when polytetrafluoroethylene (C) and an alkyl (meth) acrylate-based polymer (D) are blended, and arrived at the present invention.

That is, the present invention provides the following resin composition for extrusion molding. (1) Lignocellulosic or cellulosic material (A)
And a polyolefin-based resin (B), wherein the resin composition is polytetrafluoroethylene (C).
, And an alkyl (meth) acrylate-based polymer (D) in an amount of 0.05 to 4.5 wt%. (2) Lignocellulosic or cellulosic material (A)
(1) The resin composition for extrusion molding according to (1), wherein the content is 20% by weight or more. (3) Lignocellulosic or cellulosic material (A)
Is a esterified lignocellulosic or cellulosic substance (A ′), wherein the resin composition for extrusion molding according to (1) or (2), (4) The modified extrusion molding according to (3), wherein the esterified lignocellulosic or cellulosic substance (A ') is maleated wood flour obtained by addition esterification of maleic anhydride to wood flour. Resin composition. (5) Polyolefin (C) having a melt flow rate of 0.1 to 200 g / 10 min (ASTM D1238, temperature 230 ° C., load 2.16 kg) and a melt flow rate of 0.01 to 200 g / 10 min ( AS
TM D1238, temperature 190 ° C, load 2.16kg)
Characterized in that it is a mixture of polyethylene (1)
The resin composition for extrusion molding according to any one of (1) to (4).

[0009]

Embodiments of the present invention will be described below in detail. The resin composition for extrusion molding of the present invention,
Lignocellulosic or cellulosic material (hereinafter referred to as wood-based material) (A) and polyolefin-based resin (B)
The most characteristic feature is that the resin composition comprising polytetrafluoroethylene (C) and an alkyl (meth) acrylate-based polymer (D). Here, polytetrafluoroethylene (C) is
It is obtained by polymerizing a monomer containing tetrafluoroethylene as a main component by a known method, and a homopolymer of tetrafluoroethylene, or a copolymer component within a range that does not impair the properties of polytetrafluoroethylene. Examples thereof include fluorinated olefins such as hexafluoropropylene, fluoroalkylethylene, and perfluoroalkylvinylether, and copolymers obtained by copolymerizing fluorinated alkyl (meth) acrylates such as perfluoroalkyl (meth) acrylate. In this case, the content of the copolymer component is 10% with respect to tetrafluoroethylene.
It is preferable that the content be not more than weight%.

Also, polytetrafluoroethylene (C)
Is added in an amount of 0.1 to 1.5 wt%, preferably 0.2 to 1.5 wt%.
1.0 wt%. If the amount is less than 0.1% by weight, the effect is not sufficiently exhibited.
If it exceeds 5% by weight, the cost is increased, which is not preferable.

On the other hand, the alkyl (meth) acrylate polymer (D) includes methyl (meth) acrylate, ethyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate,
Dodecyl (meth) acrylate, tridodecyl (meth)
It means a homopolymer of an alkyl (meth) acrylate such as acrylate or a copolymer of a monomer copolymerizable with these alkyl (meth) acrylates. Monomers copolymerizable with the alkyl (meth) acrylate include styrene monomers such as styrene; vinyl cyanide monomers such as acrylonitrile; vinyl ether monomers such as vinyl methyl ether; vinyl acetate and the like. Vinyl carboxylate monomers; olefin monomers such as ethylene and propylene; and diene monomers such as butadiene and isoprene.

In particular, in the present invention, the alkyl (meth) acrylate polymer (D) has 5 to 5 carbon atoms.
30 alkyl (meth) acrylates and 1 to 4 carbon atoms
Is preferred. For example, a copolymer of dodecyl methacrylate and methyl methacrylate can be preferably used. The amount of the alkyl (meth) acrylate-based polymer (D) added is 0.0
The content is 5 to 4.5 wt%, preferably 0.5 to 3.0 wt%. If the amount is less than 0.05% by weight, the polytetrafluoroethylene (C) cannot be dispersed sufficiently uniformly, and if it exceeds 4.5% by weight, it increases the cost and is not preferable.

The alkyl (meth) acrylate polymer (D) and polytetrafluoroethylene (C)
Is preferably 0.2 or more, more preferably 1.0 or more in terms of the weight ratio of (D) / (C). (D) / (C)
If the weight ratio is less than 0.2, the dispersibility of polytetrafluoroethylene (C) may be reduced.

Such polytetrafluoroethylene
(C) and alkyl (meth) acrylate polymer (D)
There is no particular limitation on the method of addition of, for example, a mixture of polytetrafluoroethylene (C) and an alkyl (meth) acrylate polymer (D), or a mixture of polytetrafluoroethylene (C) and an alkyl (meth) acrylate. A polymer obtained by polymerizing a monomer having an ethylenically unsaturated bond in a liquid obtained by mixing and dispersing the polymer (D), and a master batch using the same material as the polyolefin (C) are added at the time of molding. Alternatively, it can be added when a masterbatch of the polyolefin-based resin composition is produced in advance.

In the present invention, the polytetrafluoroethylene (C) and the alkyl (meth) acrylate-based polymer (D) are used as a resin composition comprising a wood-based material (A) and a polyolefin-based resin (B). It is contained in. Here, as the wood-based material (A), a substance containing lignocellulose, cellulose or a derivative thereof, which has been conventionally used as a filler for a resin, can be used without limitation. For example, wood-based materials obtained from wood-based materials or unused wood-based materials as industrial waste in the wood industry, such as wood powder, wood pulp, and sander powder generated during polishing of particle board, can also be used. Further, those obtained by neutralizing wood acid (lepulinic acid, acetic acid, formic acid, etc.) with urea, sodium carbonate or the like can also be used. In particular, in the present invention, it is preferable to use an esterified lignocellulosic or cellulosic substance (A ') (hereinafter, referred to as an esterified wooden material) as the wooden material (A). This esterified wood-based material (A ′) is the same as the wood-based material (A) described above.
Polybasic anhydride is chemically bonded to the hydroxyl group present in the polymer via an ester group, and has an excellent affinity for thermoplastic resins such as polyolefin resins as compared with untreated wood-based materials. Have. The polybasic acid anhydride includes, for example, maleic anhydride, phthalic anhydride, succinic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, itaconic anhydride and adipic anhydride. In particular, it is preferable to use maleated wood flour using maleic anhydride as the polybasic anhydride. The ratio of polybasic acid anhydride introduced into the wood-based material by esterification is approximately 0.5 to 20 wt.
%, Preferably 1.0 to 10 wt%. The content of the wood-based material (A) in the resin composition is preferably 20% by weight or more, particularly preferably 30% by weight or more.

The polyolefin resin (B) is a homopolymer or copolymer of an α-olefin having 2 to 20 carbon atoms. Examples of the polyolefin-based resin (B) include homopolymers of α-olefins such as polyethylene, polypropylene, polybutene and poly-4-methyl-1-pentene, ethylene / propylene copolymers, and ethylene / α.
-Olefin copolymers, α-olefin copolymers such as propylene / α-olefin copolymers, and these may be used alone or as a mixture of two or more at any mixing ratio. it can. In particular, because the resin composition of the present invention is used for profile extrusion molding, polyolefin resin
ASTM D1238 when (B) is polypropylene
230 ° C, 2.1 defined by (JIS K7210)
Melt flow rate (MFR) under a load of 6 kg is 0.1 to 200 g / 10 min, preferably 0.1 to 200 g / 10 min.
If the material of 5 g / 10 min is polyethylene, AST
MD1238 (JIS K7210) 19
It is preferable to use one having a melt flow rate (MFR) at 0 ° C. and a load of 2.16 kg of 0.01 to 200 g / 10 min, preferably 0.01 to 0.5 g / 10 min. In particular, in the present invention, it is preferable to use a mixture of polypropylene and polyethylene, and the preferred mixing ratio is polypropylene: polyethylene = 3 by weight.
0 to 80: 70 to 20.

In the present invention, the woody material (A)
The resin composition can be used without any particular limitation as long as it is a resin composition composed of the polyolefin-based resin (B) and the resin composition itself. However, it is most effective to use a resin composition having excellent extrudability. Preferred resin compositions include, for example, a polyolefin-based resin composition obtained by further adding an organic peroxide and a modified polyolefin to a wood-based material (A) and a polyolefin-based resin (B) and kneading the mixture. In this case, the heating and kneading conditions are 150 to 260 ° C., preferably 170 to 230 ° C., for 10 seconds to 30 minutes, preferably 30 seconds to 5 minutes, and the mixing ratio of (A) and (B) 0 to 1% by weight, preferably 0.008 to 0.1% by weight of the organic peroxide, and 0.1% by weight of the modified polyolefin to the total amount.
It is 1 to 10 wt%, preferably 0.5 to 8 wt%.

Another preferred example is a mixture obtained by adding an organic peroxide and a polybasic anhydride to a wood-based material (A) and a polyolefin-based resin (B) and kneading the mixture. . In this case, it is of course possible to mix and heat-knead these materials at the same time. However, the wood-based material (A) and the polybasic acid anhydride are heated and kneaded in advance to obtain an esterified wood-based material (A ′). After that, it is preferable to use a mixture obtained by blending the polyolefin resin (B) and the organic peroxide and kneading with heat. The heating and kneading conditions for obtaining (A ′) are 120 to 260 ° C., preferably 140 to 23 ° C.
It is 10 seconds to 30 minutes at 0 ° C., preferably 30 seconds to 10 minutes, and the conditions for heating and kneading (A ′), (B) and the organic peroxide are 150 to 260 ° C., preferably 170 to 230 ° C.
For 10 seconds to 30 minutes, preferably 30 seconds to 5 minutes. The mixing ratio of the organic peroxide is 0 to 1% by weight, preferably 0.001%, based on the total amount of (A) and (B).
8 to 0.1 wt%, polybasic anhydride 0.5 to 20 wt
%, Preferably 0.5 to 15 wt%.

Further, the polyolefin resin composition used in the present invention may contain, if necessary, an inorganic filler such as talc, calcium carbonate, mica, glass fiber or the like, or an organic filler such as polyester or polyamide fiber. Of course, it is also possible to add other components such as various additives such as a flame retardant, a stabilizer, an ultraviolet absorber, an antioxidant, and a plasticizer, and a coloring agent such as a dye and a pigment. Further, it is of course possible to use other known lubricants, processing aids, and foaming agents in combination.

The resin composition of the present invention can be formed into various molded products by molding using a general profile extrusion molding machine. The field of use of the obtained molded article is not particularly limited, and it can be used in many fields in which thermoplastic resins have been conventionally used. However, it can be used in fields such as electric parts, industrial parts, and building materials. It can be suitably used, and in particular, it can be particularly suitably used for housing members, building materials, and home electric appliances.

[0021]

[Effect] "Saddle" at the edge of a resin composition comprising a wood-based material (A) and a polyolefin-based resin (B) in which polytetrafluoroethylene (C) and an alkyl (meth) acrylate-based polymer (D) are formed. It is not clear how the polytetrafluoroethylene (C) has high crystallinity and low intermolecular force, so it has a function to prevent the resin from being cut during the extrusion molding due to the slight stress due to the high crystallinity and low intermolecular force. The alkyl (meth) acrylate polymer (D) improves the compatibility between polytetrafluoroethylene (C) and polyolefin resin (B), and converts polytetrafluoroethylene (C) into polyolefin resin. Since the resin composition is uniformly dispersed in the resin (B), the resin composition comprising the wood-based material (A) and the polyolefin-based resin (B) is formed by extrusion molding. And when it is believed that the function of preventing the molded product split finely in friction with the die.

[0022]

Next, an embodiment of the present invention will be described. The raw materials used and the evaluation method are as follows. <Wood-based material (A)> Wood flour (Lignocell S150TR, manufactured by Rettenmeier, Germany) was used.
Hereinafter referred to as wood flour. Esterified wood-based material (A '): Wood flour (Lignocell S150TR, manufactured by Rettenmeier, Germany) and maleic anhydride are supplied to a continuous kneader, heated and kneaded at 150 ° C for 8 minutes, and esterified. A wood-based material (hereinafter referred to as MA wood flour) was obtained. The addition amount of maleic anhydride introduced by esterification was 1.5 wt% with respect to the wood flour. <Polyolefin resin (B)> Polypropylene (homopolypropylene, MFR = 0.5 g / 10 min, specific gravity =
0.9) was used. Hereinafter, it is referred to as PP. Polyethylene (high density polyethylene, MFR = 0.03 g / 10 min,
Specific gravity = 0.95) was used. Hereinafter, it is referred to as PE. The melt flow rate (MFR) is the result of measurement at 230 ° C. under a load of 2.16 kg for polypropylene and 190 ° C. under a load of 2.16 kg for polyethylene in accordance with ASTM D1238. <Organic peroxide> 1,3-bis (t-butylperoxyisopropyl) benzene was used. Hereinafter, it is referred to as PO. <Polytetrafluoroethylene (C)> Polytetrafluoroethylene (trade name: Lubron L-5, manufactured by Daikin) was used. Hereinafter, it is referred to as PTFE. <Alkyl (meth) acrylate-based polymer (D)> A copolymer of dodecyl methacrylate and methyl methacrylate in a weight ratio of 1: 1 was used. Hereinafter, it is referred to as AMA.

<Measurement Method for Evaluating Moldability> Wood-based material (A), polyolefin-based resin (B) and organic peroxide were heated and kneaded in a continuous kneader at 180 ° C. for 3 minutes, and then a sheet manufactured by Horai Co., Ltd. Using a pelletizer, pellets of 4 mm square were formed. Next, polytetrafluoroethylene (C) and an alkyl (meth) acrylate-based polymer (D) were dry-blended to the obtained pellets, and an extruder (L / D = 2) of a Labo Plastomill manufactured by Toyo Seiki Co., Ltd.
5, screw diameter = 20mm, full flight, compression ratio =
2.0) and attached to the extruder.
ASTM ExtrusionDi described in D2230
e No. 1. Extrusion molding was performed from Garvey Type (hereinafter abbreviated as "Garve die"), and the state of the edge of the molded product was observed. In addition, the profile extrusion molding conditions are as follows.
0 rpm, set temperature: C1 = 170 ° C., C2 = 180
° C, C3 = 185 ° C, D = 180 ° C. The appearance of the edge followed the following criteria for each of edge P, edge N, and edge S. ○: no swelling was observed △: a little swelling was observed ×: remarkably swelling was observed

Examples 1 to 7 and Comparative Examples 1 to 3 The resin compositions having the compounding ratios shown in Table 1 were subjected to profile extrusion molding, and profile extrusion moldability was evaluated. The results are also shown in Table 1.

[0025]

[Table 1]

As is clear from Table 1, the resin composition according to the present invention exhibited excellent profile extrusion moldability. In particular, despite the extremely high content of the wood-based material (A ') of 50 wt% (Examples 4 to 7), the formability of the edge P having a small radius (R) is also improved. Furthermore, those having an addition amount of polyfluoroethylene (C) of 0.8 wt% (Example 7) exhibited excellent moldability. On the other hand, when the polyfluoroethylene (C) and the alkyl (meth) acrylate-based polymer (D) were not added, even if the content of the wood-based material (A ′) was 30 wt% (Comparative Example 1), the edge was not increased. In addition, the molding process itself was difficult with 50 wt% (Comparative Example 2).
Furthermore, when only the polyfluoroethylene (C) was added and the alkyl (meth) acrylate-based polymer (D) was not added (Comparative Example 3), no improvement in moldability was observed.

[0027]

As described above, the resin composition of the present invention can be used even when the mixing ratio of the woody material (A) of the resin composition comprising the woody material (A) and the polyolefin resin (B) is increased. "Sasagure" has been greatly improved, and even if a complex mold having a small edge radius (R) is used, it is possible to perform a clean molding according to the mold. Therefore, it has become possible to provide a wide variety of molded products having a high blending ratio of the wood-based material (A), that is, having an excellent woody feel.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 27/18 C08L 27/18 33/08 33/08 // B29K 1:00 23:00 B29L 31:00 (72) Inventor Matsuda ▲ Hide ▼ Akira 1515 Nakatsu-cho, Marugame-shi, Kagawa Prefecture F-term in Okura Industrial Co., Ltd. BG043 BG053

Claims (5)

[Claims] 1. A resin composition comprising a lignocellulosic or cellulosic substance (A) and a polyolefin resin (B), wherein the resin composition comprises polytetrafluoroethylene (C) in an amount of 0.1 to 1. 5 wt% and alkyl (meth)
Acrylate-based polymer (D) is 0.05 to 4.5 wt%
A resin composition for profile extrusion molding characterized by containing. 2. The resin composition for extrusion molding according to claim 1, wherein the content of the lignocellulosic or cellulosic substance (A) is 20% by weight or more. 3. The lignocellulosic or cellulosic material (A) is an esterified lignocellulosic or cellulosic material (A ′).
Or the resin composition for extrusion molding according to 2. 4. The variant according to claim 3, wherein the esterified lignocellulosic or cellulosic substance (A ′) is maleated wood flour obtained by addition esterification of maleic anhydride to wood flour. Extrusion molding resin composition. 5. A polyolefin (C) having a melt flow rate of 0.1 to 200 g / 10 min (ASTM D123).
8, temperature 230 ° C., load 2.16 kg) polypropylene and melt flow rate 0.01 to 200 g / 10 min (ASTMD1238, temperature 190 ° C., load 2.16 k)
The resin composition for extrusion molding according to any one of claims 1 to 4, wherein the resin composition is a mixture of g) polyethylene.