JP2003003016A - Resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition which contains a polyolefin resin and an inorganic filler and has excellent uniform dispersibility and good productivity. SOLUTION: The resin composition contains a vinyl polymer obtained by polymerizing a vinyl monomer at a temperature of 180-350 deg.C, a polyolefin resin and an inorganic filler.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a resin composition containing a polyolefin resin and an inorganic filler.

[0002]

2. Description of the Related Art There is known a technique for improving impact resistance and flame retardancy by adding an inorganic filler such as talc and magnesium hydroxide to a polyolefin resin. Since the inorganic filler is difficult to mix with the polyolefin resin,
It is also known to improve the uniform dispersibility by adding a fatty acid or a wax (JP-A-9-302099 and JP-A-11-1581). However, this method may have insufficient uniform dispersion depending on the conditions,
Limited use. A method of mixing a surface-treated inorganic filler with a polyolefin is also known (Japanese Patent Laid-Open No. 2000-63580). However, in this method, the process for applying the surface treatment to the inorganic filler has poor workability, and the productivity may be poor in mass production.

[0003]

SUMMARY OF THE INVENTION The present invention has been made by paying attention to the problems of the prior art as described above. An object of the invention is to provide a resin composition containing a polyolefin resin and an inorganic filler, which has excellent uniform dispersibility and good productivity.

[0004]

In order to achieve the above object, the resin composition according to claim 1 is a vinyl polymer obtained by polymerizing a vinyl monomer at a temperature of 180 to 350 ° C. It is characterized by containing a polyolefin resin and an inorganic filler. The resin composition according to claim 2 is the resin composition according to claim 1, wherein the blending amounts of the vinyl polymer and the polyolefin resin are:
Based on 100 parts by weight of the inorganic filler, each of 0.1
To 200 parts by mass and 30 to 2000 parts by mass. The invention according to claim 3 relates to a wire coating resin composition containing a vinyl polymer obtained by polymerizing a vinyl monomer at a temperature of 180 to 350 ° C., a polyolefin resin, and an inorganic filler. .

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments embodying the present invention will be described below. In the present specification, (meth) acrylic means acrylic or methacrylic.

In the present invention, the vinyl monomer is added in the range of 180-350.
The present invention relates to a resin composition containing a vinyl polymer obtained by polymerizing at a temperature of ° C, a polyolefin resin, and an inorganic filler.

The polyolefin resin is a polymer having an olefin unit as a main constituent unit, and specific examples thereof include polyethylene, low density polyethylene, high density polyethylene, polypropylene, a copolymer of ethylene and propylene, ethylene and ethylene and propylene. Other than α
-Olefin copolymer, propylene / ethylene and α-olefin other than propylene, ethylene / acrylic acid ester copolymer, propylene / acrylic acid ester copolymer, ethylene / vinyl acetate copolymer Etc. The above-mentioned polyolefin resin may have a monomer unit other than the original constitutional unit such as styrene, if necessary, as long as the performance thereof is not impaired.

The inorganic filler is a component which functions to impart impact resistance and flame retardancy to the composition. Specific examples include calcium carbonate, talc, clay, silica, alumina, magnesium hydroxide, aluminum hydroxide and the like.

In the resin composition of the present invention, the proportion of the polyolefin resin is 3 based on 100 parts by mass of the inorganic filler.
It is preferably from 0 to 2000 parts by mass, and from 50 to 10
It is more preferably 100 parts by mass. If the proportion of the polyolefin-based resin is too large, impact resistance and flame retardancy may be insufficient, and if it is too small, the moldability of the resin composition may be deteriorated.

The vinyl polymer used in the present invention is a component that improves the uniform dispersibility of the resin composition, that is, a component that functions as a dispersant, and contains 180 to 35 vinyl monomers.
It is obtained by polymerizing at a temperature of 0 ° C. (hereinafter, also simply referred to as vinyl polymer). As a vinyl monomer,
Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth)
(Meth) acrylic acid ester such as 2-ethylhexyl acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, glycidyl (meth) acrylate, (meth) acrylic acid, styrene, α-methyl Examples thereof include styrene and acrylonitrile.
A (meth) acrylic polymer having (meth) acrylic acid ester or (meth) acrylic acid as a main constituent monomer unit is preferable in order to make the resulting composition particularly excellent in weather resistance.

The vinyl monomer is polymerized at a temperature of 180 to 350 ° C. 200 to 320 is preferable, 220 to 30
0 ° C is more preferable. If the polymerization temperature is too low, the resulting vinyl polymer will have a large molecular weight, and it will be difficult to uniformly disperse the resin composition, and the productivity of the resin composition may deteriorate. When a large amount of a polymerization initiator or a chain transfer agent is used to obtain a vinyl polymer having a small molecular weight at a low polymerization temperature, the vinyl polymer is likely to be colored or have poor weather resistance. If the polymerization temperature is too high, the vinyl polymer tends to be colored. The weight average molecular weight of the vinyl polymer is preferably 1,000 to 30,000,
0 to 20000 is more preferable. If the molecular weight is too small, the resulting resin composition may have insufficient heat resistance, and if the molecular weight is too large, the resin composition may not be uniformly dispersed, and the productivity of the resin composition may also deteriorate. is there.

The vinyl polymer can be produced by solution polymerization, bulk polymerization or the like. Further, it can be produced by a method such as continuous polymerization, semi-continuous polymerization, batch polymerization,
A vinyl polymer produced by continuous polymerization, especially continuous polymerization using a stirred tank reactor, is particularly preferable because of its excellent performance of uniformly dispersing the resin composition. Such continuous polymerization can be carried out by a known method (Tokusho Sho-5).
7-502171, JP-A-59-6207, JP-A-60-215007).

The resin composition of the present invention has a vinyl polymer content of 0.1 to 2 based on 100 parts by mass of the inorganic filler.
It is preferably 100 parts by mass, more preferably 5 to 100 parts by mass. If the proportion of the vinyl polymer is too small, the uniform dispersibility of the resin composition may be insufficient, and if it is too large, the moldability of the resin composition may be deteriorated.

The resin composition of the present invention can be obtained by mixing the above components. The mixing method is not particularly limited, for example, a vinyl polymer, a polyolefin-based resin and an inorganic filler are blended, the above-mentioned additives are added if necessary, and a general method such as a kneader, a Banbury mixer, or a Conti It can be obtained by mixing and kneading using a near mixer or an extruder.

The resin composition of the present invention can be used as various molding materials, but is particularly useful as an electric wire coating material.
In the case of wire coating material use, the weight average molecular weight is 1000-
A resin composition using 30,000 vinyl polymers is preferable because it has an excellent balance of hardness, elongation, insulating property, weather resistance and the like in addition to the above characteristics. The hardness is preferably a Shore hardness of A80 or more.

The resin composition of the present invention may be blended with various additives depending on the purpose. For example, salicylate-based, hydroxybenzoate-based, benzotriazole-based, hindered amine-based light stabilizers, hindered phenol-based, phosphite-based, sulfite-based antioxidants, phosphate-based organic phosphorus, organic halogen Flame retardants such as compounds, anionic surfactants, cationic surfactants, nonionic surfactants, antistatic agents such as amphoteric surfactants, pigments, antibacterial agents, antifungal agents, foaming agents, foaming agents. Examples include auxiliary agents and lubricants.

[0017]

EXAMPLES Next, the above-mentioned embodiment will be described more specifically with reference to Examples and Comparative Examples. In addition, "part" in each of the following examples means "part by mass".

(Production Example of Vinyl Polymer) (Production Example 1) A pressure type stirred tank reactor having a capacity of 300 ml equipped with a heat transfer heater was filled with ethyl 3-ethoxypropionate and the temperature was set to 230 ° C. The pressure is adjusted by the regulator to a gauge pressure of 2.45 to 2.65 MPa (25 to 27 kg
/ Cm ² ). Then, while keeping the pressure of the reactor constant, ethyl acrylate (hereinafter referred to as EA) 1
A monomer mixture consisting of 00 parts, 20 parts of methyl ethyl ketone, and 0.5 parts of ditertiarybutyl peroxide as a polymerization initiator was fed from a raw material tank to a reactor at a constant feed rate (23 g / min, residence time: 13 minutes). Continuous supply was started. Then, the reaction liquid corresponding to the supply amount of the monomer mixture was continuously withdrawn from the outlet. Immediately after feeding the liquid, the reaction temperature was once lowered and then increased by the heat of polymerization, but the reaction temperature was maintained at 230 ° C. by controlling the heater. After the start of the supply of the monomer mixture, the time when the temperature became stable was set as the starting point of the reaction solution collection, and the reaction was continued for 154 minutes. As a result, 2000 g of the monomer mixture was supplied and 1950 g of the reaction solution was recovered. . The obtained reaction liquid was introduced into a thin film evaporator, and the temperature was 235 ° C. and 4000 Pa (30
Under reduced pressure of (mmHg), volatile components such as unreacted monomers and solvents are removed, and about 1500 g of a liquid resin, Polymer 1
Got

As a result of gas chromatographic analysis, the unreacted monomer in the liquid resin was 0.5% or less. Tetrahydrofuran was used as a solvent, and the weight average molecular weight (hereinafter referred to as Mw) of the polymer 1 obtained by converting the molecular weight obtained by gel permeation chromatography (hereinafter referred to as GPC) into polystyrene was 1450.

(Production Examples 2 to 4) Polymers 2 to 4 were obtained in the same manner as in the production method of the polymer 1 except that the composition of the monomer used was changed as shown in Table 1. . Table 1 shows Mw of the obtained polymer. In Table 1, BA represents butyl acrylate and MEA represents methoxyethyl acrylate.

[0021]

[Table 1]

(Preparation of Resin Composition and Evaluation of Moldability) (Example 1) As an olefin resin, an ethylene-ethyl acrylate copolymer (hereinafter referred to as EEA. J-LEX EEA A1150 manufactured by Nippon Polyolefin Co., Ltd.)
It was used. ) 10 g, magnesium hydroxide as an inorganic filler (Kisma 5 manufactured by Kyowa Chemical Co., Ltd. was used.)
20 g and 0.2 g of the polymer 1 as a dispersant for the inorganic filler are Laboplast mill 30C1 manufactured by Toyo Seiki Co., Ltd.
50 (kneading rotor used was R-30),
Kneading was started at 200 ° C. and a rotation speed of 60 rpm. Then, the time at which the kneading torque reaches equilibrium (hereinafter referred to as gelation time) and the torque at that time (hereinafter referred to as equilibrium torque) were measured, and as a result, 0.7 minutes and 10.7, respectively.
It was found to be N · m (1.09 kgf · m), the olefin resin and the inorganic filler were rapidly and uniformly mixed (the gelation time was short), and the kneading load was small (the equilibrium torque was small). That is, the productivity of the resin composition is good,
It was found that the obtained resin composition has excellent uniform dispersibility.

(Examples 2 to 4, Comparative Examples 1 and 2) The dispersant of the inorganic filler used was changed as shown in Table 2, and the gelation time was changed according to the method shown in Example 1 except for the above. And the equilibrium torque was measured. Comparative Example 1 used no dispersant and Comparative Example 2 used stearic acid as the dispersant. It was found that in Example, uniform mixing was easy and the kneading load was small, whereas in Comparative Example, uniform mixing was difficult and the kneading load was large.

[0024]

[Table 2]

(Preparation, Molding, and Evaluation of Resin Composition (Tensile Test, Hardness Measurement)) (Example 5) 100 parts of EEA, 20 parts of Polymer 2 and 200 parts of magnesium hydroxide were mixed, and Plastic Engineering Laboratory Co., Ltd. Twin screw extruder (temperature setting: C1 = 170
℃, C2 = 175 ℃, C3 = 180 ℃, C4 = 180 ℃, H = 18
The mixture was kneaded at 0 ° C. and D = 180 ° C. to prepare a pelletized composition.

The composition was kneaded with two 5-inch test rolls at 180 ° C. for 5 minutes, and then hot pressed at 190 ° C. to obtain a sheet-shaped molded product. The tensile test sheet had a thickness of 2 mm and the Shore hardness sheet had a thickness of 6 mm.

For the tensile test, a tensile tester series 5560 manufactured by Instron Co., Ltd. was used, and JIS K7161 was used.
Dumbbell No. 2, tensile speed 10 mm / min, and elongation at break were measured. As a result, the growth rate is 16
It was 5%. Shore hardness was measured using a type A durometer according to JIS K7215. As a result, the Shore hardness was 88.

(Example 6 and Comparative Example 3) The dispersant of the inorganic filler used was changed as shown in Table 3, and other than that,
The tensile test and the Shore hardness were measured according to the method described in Example 5. In Comparative Example 3, no dispersant was used. In the comparative example, the elongation rate was small. It is speculated that the reason is that the resin composition has poor uniform dispersibility.

[0029]

[Table 3]

Example 7 Polypropylene resin (hereinafter,
It is called PP. Novatec PP manufactured by Nippon Polychem Co., Ltd.
FY-4 was used. ) 100 parts, 5 parts of polymer 2 and talc (Talc PK-50 manufactured by Fuji Talc Industry Co., Ltd.)
It was used. ) Mixing 30 parts and by the method shown in Example 5,
Tensile tests and Shore hardness were measured. The results are shown in Table 4.

(Comparative Examples 4 to 5) The dispersant of the inorganic filler used was changed as shown in Table 4, and other than that, Example 7
The tensile test and the shore hardness were measured according to the method shown in. Comparative Example 4 used stearic acid as the dispersant and Comparative Example 5 did not use the dispersant. In the comparative example, the elongation rate was small. It is speculated that the reason is that the resin composition has poor uniform dispersibility.

[0032]

[Table 4]

[0033]

EFFECT OF THE INVENTION A resin composition containing a polyolefin resin and an inorganic filler, which has excellent uniform dispersibility and good productivity, was obtained. It is considered that the effect of high elongation was obtained due to the excellent uniform dispersibility.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01B 3/00 H01B 3/00 A 3/44 3/44 A FF term (reference) 4J002 BB03X BB06X BB07X BB12X BB15X BC02W BC092 BG01W BG04W BG05W BG06W BG07W BG10W DE076 DE146 DE236 DJ016 DJ046 FD016 FD136 GT00 4J038 CB021 CB022 CB041 CB042 CB051 CB052 CB081 CB082 CC011 CC012 CG031 CG032 CG141 CG142 CG161 CG162 CH031 CH032 CH071 CH072 CH121 CH122 CH171 CH172 HA186 HA216 HA286 HA446 HA526 HA536 KA08 NA11 NA15 PB09 5G303 AA06 AA10 AB20 BA12 CA01 CA09 CC02 5G305 AA02 AA14 AB36 BA15 CA01 CD01

Claims (3)

[Claims] 1. A resin composition containing a vinyl polymer obtained by polymerizing a vinyl monomer at a temperature of 180 to 350 ° C., a polyolefin resin, and an inorganic filler. 2. The blending amounts of the vinyl polymer and the polyolefin resin are 0.1 to 200 parts by mass and 30 to 200 parts by mass, respectively, based on 100 parts by mass of the inorganic filler.
The resin composition according to claim 1, which is 0 part by mass. 3. An electric wire coating resin composition containing a vinyl polymer obtained by polymerizing a vinyl monomer at a temperature of 180 to 350 ° C., a polyolefin resin and an inorganic filler.