JP2001114944A - Polyolefin based resin composition highly filled with vegetable filler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide high filling polyolefin based resin compositions highly filled with vegetable fillers which are suited in obtaining molded articles having both excellent properties and durability and excellent woody touch and have good moldability. SOLUTION: The polyolefin based resin compositions are obtained by kneading a composition comprising 100 pts.wt. polyolefin based resin, 100-400 pts.wt. vegetable filler, 1-20 pts.wt. modified polyolefin, and 0.1-10 pts.wt. mixture of an α,β-unsaturated carboxylic acid monomer with 0.1-10 wt.%, based on the monomer, a polymerization initiator in the molten state of said polyolefin based resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention is suitable for obtaining a molded article having a woody appearance, having both the advantages of plastics such as easy moldability and durability and the advantages of woody materials such as warmth and heat retention. The present invention relates to a highly filled polyolefin resin composition containing a plant filler.

[0002]

2. Description of the Related Art Conventionally, a composite resin composition is prepared by adding a plant filler such as wood flour to a thermoplastic resin such as polyolefin, and the composition is molded to give a woody appearance. Various attempts have been made to obtain molded articles having the same.

However, when a plant-based filler is added to a thermoplastic resin, the more the amount of the plant-based filler is added, the lower the thermal fluidity of the resin composition, and the heat generated during molding causes the plant-based filler to generate heat. Problems such as burning and giving off odor and deteriorating physical properties arise. In particular, when the amount of the plant-based filler in the entire resin composition is as high as 50% by weight or more, the above problem becomes more remarkable.

To cope with such a problem, for example, Japanese Patent Application Laid-Open No. Sho 63-236571 discloses a method in which 100 parts by weight of a styrene resin is mixed with 10 to 400 plant fiber powders.
It is disclosed that a thermoplastic resin composition containing parts by weight is molded by a molding method such as extrusion molding or compression molding to obtain a molded product having a woody feel.

In Japanese Patent Application Laid-Open No. 61-236858, 10 to 100 parts by weight of a wood-based filler, 100 parts by weight of a thermoplastic resin such as an acrylic resin,
It is disclosed that a thermoplastic resin composition containing ８０80 parts by weight is molded by a molding method such as extrusion molding or injection molding to obtain a molded product having a woody feel.

However, a molded article obtained from the thermoplastic resin composition as disclosed in the above two disclosures is a molded article obtained from a thermoplastic resin composition to which an inorganic filler such as talc, calcium carbonate and glass fiber is added. There is a problem in that, for example, physical properties such as bending strength are inferior to products, and usage applications are restricted.

[0007]

SUMMARY OF THE INVENTION In view of the above-mentioned conventional problems, an object of the present invention is to provide a molded article having both excellent physical properties and durability and an excellent woody feel, and to have good moldability. An object of the present invention is to provide a highly filled polyolefin-based resin composition with a plant-based filler.

[0008]

The highly filled polyolefin resin composition according to claim 1 is characterized in that 100 parts by weight of polyolefin resin is added to 100 parts by weight of plant filler.
To 400 parts by weight, 1 to 20 parts by weight of a modified polyolefin, and a mixture of an α, β-unsaturated carboxylic acid-based monomer and 0.1 to 10% by weight based on the monomer.
The composition to which 1 to 10 parts by weight is added is kneaded in a molten state of the polyolefin resin.

The polyolefin resin used in the present invention may be a homopolymer of an olefin monomer, a copolymer of two or more olefin monomers or an olefin monomer and the olefin monomer. It may be a copolymer with a polymerizable monomer that can be copolymerized, for example, polyethylene, polypropylene, polybutene, poly-4-methyl-1-pentene, ethylene-
Examples thereof include a propylene copolymer and an ethylene-vinyl acetate copolymer, and among them, polypropylene is preferably used. These polyolefin resins may be used alone or in combination of two or more.

[0010] The plant-based filler used in the present invention may be any plant-based filler capable of imparting a woody appearance such as a woody appearance, soft feel, warmth, and heat retention to a molded article. Wood, pulp, paper, plywood, particle board, MDF, LVL, cuttings of plant materials such as bamboo, grinding chips, sawdust, crushed materials such as wood flour, husks such as grains and fruits, or crushed husks thereof And plant fibers such as jute and kenaf, and crushed products thereof. Of these, wood flour is preferably used. These plant-based fillers
They may be used alone or in combination of two or more.

In the highly filled polyolefin resin composition (hereinafter simply referred to as "polyolefin resin composition") of the present invention, 100 parts by weight of the polyolefin resin is added to the plant filler. 100-4
It is necessary that 00 parts by weight be added.

When the amount of the plant filler is less than 100 parts by weight based on 100 parts by weight of the polyolefin resin,
Even when the modified polyolefin described below is added, a sufficient effect of improving the physical properties may not be obtained as compared with the case where the modified polyolefin is not added. Conversely, the amount of the plant-based filler added to 100 parts by weight of the polyolefin-based resin Is 400
If the amount is more than 10 parts by weight, the moldability deteriorates, and as a result, the physical properties decrease.

The modified polyolefin used in the present invention is obtained by reacting the polyolefin resin with a compound having a functional group capable of reacting with the polyolefin resin.
It is obtained by modifying a polyolefin resin by introducing a functional group. These modified polyolefins may be used alone or in combination of two or more.

As the compound having a functional group capable of reacting with the polyolefin resin, a compound having a high affinity with the above-mentioned plant-based filler is preferable, and a compound having a high reactivity with a hydroxyl group is particularly preferable. Examples include unsaturated carboxylic anhydrides, unsaturated carboxylic acids, unsaturated carboxylic esters, unsaturated carboxylic imides, epoxy compounds, isocyanate compounds, cyanoethyl compounds and the like.
Specifically, for example, maleic anhydride, maleic acid, itaconic anhydride, itaconic acid, acrylic acid, methacrylic acid, acrylic acid ester, methacrylic acid ester, and the like, among which maleic anhydride and itaconic anhydride, etc. The unsaturated carboxylic acid anhydride is preferably used. These compounds may be used alone or in combination of two or more.

In the polyolefin resin composition of the present invention, it is necessary that 1 to 20 parts by weight of the modified polyolefin is added to 100 parts by weight of the polyolefin resin.

If the amount of the modified polyolefin is less than 1 part by weight per 100 parts by weight of the polyolefin resin, a sufficient effect of improving the physical properties may not be obtained. If the amount exceeds 20 parts by weight, the elastic modulus of the polyolefin-based resin composition may be reduced and the strength may be insufficient.

The α, β-unsaturated carboxylic acid monomer used in the present invention includes, for example, α, β-unsaturated carboxylic acid, α, β-unsaturated carboxylic acid ester, α, β-unsaturated carboxylic acid ester.
Examples thereof include unsaturated carboxylic acid amides, and among them, those having a boiling point higher than the molding temperature of the polyolefin resin composition of the present invention are preferably used. These α, β
-Unsaturated carboxylic acid monomers may be used alone or in combination of two or more.

Specific examples of the α, β-unsaturated carboxylic acid include, for example, methacrylic acid, acrylic acid, crotonic acid,
Isocrotonic acid, itaconic acid and the like. These α, β-unsaturated carboxylic acids may be used alone or in combination of two or more.

The α, β-unsaturated carboxylic acid ester includes, for example, acrylic acid ester and methacrylic acid ester. These α, β-unsaturated carboxylic esters may be used alone or in combination of two or more.

Specific examples of the acrylate include, for example, allyl acrylate, isobutyl acrylate, 2- (5-ethyl-2-pyridyl) ethyl acrylate, 2-ethylhexyl acrylate, glycidyl acrylate, acryl 2-cyanoethyl acid, acrylic acid-2-
Examples include hydroxyethyl, hydroxypropyl acrylate, n-butyl acrylate, t-butyl acrylate, cyclohexyl acrylate, and the like. These acrylates may be used alone or in combination of two or more.

Specific examples of the methacrylic acid ester include:
For example, ethyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, tridecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, Benzyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, dimethylaminoethyl methacrylate, dimethylaminoethyl methacrylate / methyl chloride salt, diethylaminoethyl methacrylate, glycidyl methacrylate, tetrahydrofurfuryl methacrylate , Allyl methacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, dimethacrylic acid-1 3-butylene glycol dimethacrylate, 1,6-hexanediol, trimethylolpropane trimethacrylate, methacrylic acid-2-ethoxyethyl or the like. These methacrylic acid esters may be used alone or in combination of two or more.

Further, specific examples of the α, β-unsaturated carboxylic acid amide include acrylamide and N-methylolacrylamide. These α, β-
The unsaturated carboxylic acid amides may be used alone or in combination of two or more.

The polymerization initiator used in the present invention includes:
Any polymerization initiator may be used as long as it can induce the polymerization of the above-mentioned α, β-unsaturated carboxylic acid monomer by heating. For example, ketone peroxide-based polymerization initiator, peroxyketal-based polymerization initiator Agents, dialkyl peroxide-based polymerization initiators, diacyl peroxide-based polymerization initiators, peroxyester-based polymerization initiators, peroxydicarbonate-based polymerization initiators, and the like. These polymerization initiators may be used alone or in combination of two or more.

Hereinafter, specific examples of the polymerization initiator will be listed.
The numbers in parentheses indicate the 10-hour half-life temperatures.

Examples of the ketone peroxide-based polymerization initiator include methyl acetoacetate peroxide. These ketone peroxide-based polymerization initiators may be used alone or in combination of two or more.

Examples of the peroxyketal polymerization initiator include, for example, 1,1-bis (t-hexylperoxy)
-3,3,5-trimethylcyclohexane (86.7
° C), 1,1-bis (t-hexylperoxy) cyclohexane (87.1 ° C), 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane (90.0 ° C) , 1,1-bis (t-butylperoxy) cyclohexane (90.7 ° C.), 1,1-bis (t
-Butylperoxy) cyclododecane (95.0 ° C.),
2,2-bis (t-butylperoxy) butane (10
3.1 ° C), n-butyl-4,4-bis (t-butylperoxy) valerate (104.5 ° C), 2,2-bis (4,4-di-t-butylperoxycyclohexyl)
And propane (94.7 ° C.). These peroxyketal-based polymerization initiators may be used alone or in combination of two or more.

As the dialkyl peroxide-based polymerization initiator, for example, di-t-butyl peroxide (12
3.7 ° C.). These diacyl peroxide-based polymerization initiators may be used alone or 2
More than one type may be used in combination.

As the diacyl peroxide-based polymerization initiator, for example, lauroyl peroxide (61.6)
° C), stearoyl peroxide (62.4 ° C),
2,4-dichlorobenzoyl peroxide (52.8
° C), octanoyl peroxide (61.5 ° C), benzoyl peroxide (73.6 ° C) and the like. These diacyl peroxide-based polymerization initiators,
They may be used alone or in combination of two or more.

Examples of the peroxyester polymerization initiator include 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (65.3 ° C.)
2,5-dimethyl-2,5-bis (2-ethylhexanoylperoxy) hexane (66.2 ° C), 1-cyclohexyl-1-methylethylperoxy-2-ethylhexanoate (67.5 ° C) ), T-hexylperoxy-2-ethylhexanoate (69.9 ° C), t-butylperoxy-2-ethylhexanoate (72.1.
° C), t-butyl peroxyisobutyrate (77.3)
C), t-hexylperoxyisopropyl monocarbonate (95.0C), t-butylperoxymaleic acid (96.1C), t-butylperoxy-3,5,5.
-Trimethylhexanoate (97.1 ° C), t-butylperoxylaurate (98.3 ° C), 2,5-dimethyl-2,5-di (m-toluoylperoxy) hexane (98.5) ° C), t-butyl peroxyisopropyl monocarbonate (98.7 ° C), t-butyl peroxy-2-ethylhexyl monocarbonate (99.0 ° C).
C), t-hexylperoxybenzoate (99.4).
C), 2,5-dimethyl-2,5-di (benzoylperoxy) hexane (99.7C), t-butylperoxyacetate (101.9C), t-butylperoxy-m-toluoyl Benzoate, t-butylperoxybenzoate (104.3 ° C.), 2,4,4-trimethylpentyl-2-hydroperoxide and the like can be mentioned. These peroxyester polymerization initiators may be used alone or in combination of two or more.

Among the above-mentioned various polymerization initiators, those having a 10-hour half-life temperature of 60 ° C. or more are preferable. If the 10-hour half-life temperature is less than 60 ° C., the α, β-unsaturated carboxylic acid-based monomer may rapidly thicken or harden during kneading or molding, resulting in impaired moldability.

Further, the 10-hour half-life temperature of the polymerization initiator is determined based on the molding temperature of the polyolefin resin composition.
It is particularly preferable to use a polymerization initiator that satisfies the relationship of [molding temperature -70 ° C <10 hour half-life temperature of polymerization initiator <molding temperature-10 ° C]. By using the polymerization initiator satisfying the above relationship, the control of the curing speed becomes easy.

The combination of the α, β-unsaturated carboxylic acid monomer and the polymerization initiator and the amount of the polymerization initiator used for the α, β-unsaturated carboxylic acid monomer are determined by the molding temperature of the polyolefin resin composition. Gel time tester under the same temperature conditions (for example, No. 1 manufactured by Yasuda Seiki Seisakusho Co., Ltd.)
It is preferable that the amount is such that the gelation time is 30 to 600 seconds, as measured by a gel time tester (type 53). It is necessary that 10 to 10% by weight of the polymerization initiator be used.

When the amount of the polymerization initiator is less than 0.1% by weight based on the α, β-unsaturated carboxylic acid monomer,
In some cases, the curing of the monomer does not proceed sufficiently. On the contrary, when the amount of the polymerization initiator exceeds 10% by weight with respect to the monomer, control of the curing speed becomes difficult and moldability may be impaired. .

In the polyolefin-based resin composition of the present invention, the α, β-unsaturated carboxylic acid-based monomer and 0.1 to 10% by weight based on 100% by weight of the polyolefin-based resin are used. It is necessary that 0.1 to 10 parts by weight of a mixture with the polymerization initiator is added.

If the amount of the mixture is less than 0.1 part by weight based on 100 parts by weight of the polyolefin-based resin, the polyolefin-based resin cannot be sufficiently plasticized, so that high filling of the plant-based filler becomes difficult. Conversely, if the amount of the mixture exceeds 10 parts by weight per 100 parts by weight of the polyolefin-based resin, the viscosity of the polyolefin-based resin composition becomes too low, and the moldability may be impaired.

The polyolefin resin composition of the present invention contains, in addition to the essential components, a polyolefin resin, a plant filler, a modified polyolefin, and a mixture of an α, β-unsaturated carboxylic acid monomer and a polymerization initiator, Lubricant, flame retardant, reinforcing agent, non-vegetable filler, foaming agent, foaming aid, coloring agent, antistatic agent, antioxidant (antioxidant) ), One or more of various additives such as a heat stabilizer, a light stabilizer, and an ultraviolet absorber.

Examples of the lubricant include hydrocarbon lubricants (eg, liquid paraffin, natural paraffin, microwax, polyethylene wax, etc.), fatty acid lubricants (eg, stearic acid, etc.), and fatty acid amide lubricants (eg, stearic acid) Amides, palmitic amides, methylene bis-stearamides, etc.), ester-based lubricants (eg, butyl acrylate, hardened castor oil, ethylene glycol monostearate, etc.), alcohol-based lubricants (eg,
Cetyl alcohol, stearyl alcohol, etc.) and metal soap lubricants (eg, zinc stearate, calcium stearate, lead stearate, etc.). These lubricants may be used alone or in combination of two or more.

The lubricant may be appropriately selected in accordance with the type and characteristics of the polyolefin resin used, but generally, the one having a strong external lubrication is preferable. The reason is,
In the case of molding a polyolefin-based resin composition highly filled with a filler by, for example, an extrusion molding method, the lower the resistance to a mold during cooling molding, the more significantly the moldability is improved. Examples of the lubricant exhibiting strong external lubrication include the above-mentioned hydrocarbon lubricant, fatty acid lubricant, metal soap lubricant and the like. The amount of the lubricant is not particularly limited, but the amount of the lubricant is 100 parts by weight of the polyolefin resin.
It is preferably from 25 to 25 parts by weight. If the amount of the lubricant added to 100 parts by weight of the polyolefin resin is less than 1 part by weight, the effect of adding the lubricant (the effect of improving the moldability) may not be sufficiently obtained. If the amount exceeds 25 parts by weight, the physical properties of the obtained molded article may be reduced.

Examples of the flame retardant include phosphate esters, halogen-containing phosphate esters, condensed phosphate esters,
Examples include phosphorus-based flame retardants such as polyphosphate esters, polyphosphates, and red phosphorus; inorganic flame retardants such as antimony trioxide and guanidine salts; and reactive flame retardants such as tetrabromobisphenol A and tribromophenol. These flame retardants may be used alone or in combination of two or more.

Examples of the reinforcing agent include glass fiber and carbon fiber. These reinforcing agents may be used alone or in combination of two or more.

Examples of the non-vegetable filler include inorganic fillers such as marble powder, calcium carbonate, talc and clay, and metal fillers such as metal powder. These non-vegetable fillers may be used alone or in combination of two or more.

Examples of the foaming agent include inorganic foaming agents such as ammonium carbonate and sodium bicarbonate, dinitrosopentamethylenetetramine, N, N'-dimethyl-N, N'-
Dinitrosoterephthalamide, benzenesulfonyl hydrazide, p-toluenesulfonyl hydrazide, P,
P'-oxybis (benzenesulfonyl hydrazide),
Organic foaming agents such as 3,3′-disulfone hydrazide phenyl sulfone, azobisisobutyronitrile, azodicarbonamide, barium azodicarboxylate, and diethylazodicarboxylate are exemplified. These foaming agents may be used alone or in combination of two or more. Further, a foaming aid may be used in combination.

By adding a foaming agent (including a foaming aid) to the polyolefin-based resin composition, the composition is foamed, for example, while being extruded, or foamed after molding to give a woody feel. It is possible to further improve.

The method for producing the polyolefin-based resin composition of the present invention is not particularly limited. For example, the essential components can be prepared by using various stirring mixers such as mixers, kneaders, rolls, and extruders equipped with a heating device. The polyolefin-based resin, plant-based filler, modified polyolefin and α,
A predetermined amount of each of the mixture of the β-unsaturated carboxylic acid-based monomer and the polymerization initiator and one or more predetermined amounts of the above-mentioned various additives to be added as necessary are added in a molten state of the polyolefin-based resin. By uniformly kneading, a desired polyolefin-based resin composition can be obtained.

The method for producing a molded article using the polyolefin resin composition of the present invention is not particularly limited, and examples thereof include an extrusion molding method, an injection molding method, a compression molding method, a calendar molding method, a stamping molding method, and a transfer molding method. By adopting a general thermoplastic resin molding method such as a molding method, and performing ordinary molding, it is possible to obtain a desired molded product such as a sheet, a film, a pipe, a deformed molded product, and a molded product. I can do it.

[0046]

In the polyolefin resin composition of the present invention, a specific amount of the modified polyolefin is added to a specific amount of the polyolefin resin as the main component, and the polyolefin resin is combined with the polyolefin resin by the coupling effect of the modified polyolefin. The adhesion at the interface with the plant-based filler is improved, and the physical properties and durability of the obtained molded article are significantly improved.

In the polyolefin resin composition of the present invention, a specific amount of the α, β-unsaturated carboxylic acid monomer is added to a specific amount of the polyolefin resin, so that the α, β-unsaturated Due to the plasticizing effect of the carboxylic acid monomer, the melt viscosity of the polyolefin resin decreases,
High filling of the plant-based filler is possible without impairing the moldability. When the plant-based filler is highly filled, the resulting molded article has more excellent physical properties, durability, and woodiness. Further, since the α, β-unsaturated carboxylic acid-based monomer contains a specific amount of a polymerization initiator, it is finally polymerized and cured, thereby further improving the physical properties and durability of the obtained molded article.

That is, by using the polyolefin resin composition of the present invention, it is possible to obtain a molded article having both excellent physical properties and durability and excellent woodiness with good moldability.

[0049]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. In the examples, “parts” means “parts by weight”.

Example 1 Cyclohexyl methacrylate 10 was previously used as an α, β-unsaturated carboxylic acid monomer.
A mixture of 0 parts and 5 parts of t-butyl peroxybenzoate as a polymerization initiator was prepared. Next, as a polyolefin resin, polypropylene (trade name: Novatec P
P ", 100 parts by Japan Polychem Co., Ltd., wood flour (45 mesh, Watanabe Chemical Co., Ltd.)
00 parts, maleic anhydride-modified polypropylene (trade name “UMEX 1001”, manufactured by Sanyo Chemical Industries, Ltd.) as the modified polyolefin and 10 parts of the previously prepared mixture 5
The polyolefin-based resin composition to which the part was added was supplied to an extruder, and a 3 mm-thick sheet-like molded product was manufactured through the steps of heat melting, kneading, and extrusion molding.

(Example 2) In the case of Example 1 except that the addition amount of wood flour (45 mesh product) as a plant-based filler was 250 parts with respect to 100 parts of polypropylene "Novatec PP" as a polyolefin resin. In the same manner as in the above, a sheet-shaped molded product having a thickness of 3 mm was produced.

Comparative Example 1 Maleic anhydride-modified polypropylene "UMEX 10" as a modified polyolefin
A sheet-shaped molded product having a thickness of 3 mm was manufactured in the same manner as in Example 1 except that "01" was not added.

Comparative Example 2 Maleic anhydride-modified polypropylene "UMEX 10" as a modified polyolefin
A sheet-shaped molded product having a thickness of 3 mm was produced in the same manner as in Example 2 except that "01" was not added. .

Four types of sheet-like molded articles obtained in Examples 1 and 2 and Comparative Examples 1 and 2 according to JIS K-7055 "Bending test method of glass fiber reinforced plastic" Was measured for bending strength (MPa).
The results were as shown in Table 1.

[0055]

[Table 1]

As is clear from Table 1, molded articles (sheet-shaped molded articles) produced using the polyolefin-based resin compositions of Examples 1 and 2 according to the present invention exhibited excellent bending strength.

On the other hand, molded articles (sheet-shaped molded articles) produced using the polyolefin resin compositions of Comparative Examples 1 and 2 to which no modified polyolefin (maleic anhydride-modified polypropylene) was added were bent. The strength was significantly poor.

[0058]

As described above, the highly filled polyolefin-based resin composition of the present invention can be used to obtain a molded article having both excellent physical properties and durability and excellent woodiness with good moldability. Suitable.

Further, a molded article produced by using the highly filled polyolefin resin composition of the present invention has excellent physical properties and durability and excellent woody feel. It is suitably used as various industrial molded products such as parts for home appliances, parts for home appliances, interior materials for buildings, building materials, furniture, and crafts.

Continued on the front page F term (reference) 4J002 AH001 BB032 BB062 BB122 BB152 BB172 BB203 BB213 CD173 EF046 EH066 EK007 EK037 EK047 EK057 EK067 EK087 EP016 FD010 FD130 FD170 FD207 FD320

Claims (1)

[Claims] 1. 100 parts by weight of a polyolefin resin, 100 to 400 parts by weight of a plant filler, 1 to 20 parts by weight of a modified polyolefin, and an α, β-unsaturated carboxylic acid-based monomer. A composition comprising a mixture of 0.1 to 10 parts by weight of a mixture with 1 to 10% by weight of a polymerization initiator, and kneaded in a molten state of the polyolefin-based resin. Highly filled polyolefin resin composition.