JPH0741607A - Resin composition - Google Patents

Abstract

PURPOSE:To provide a lightweight resin composition moldable to desired shape through hot compression molding or extrusion and excellent in secondary processability. CONSTITUTION:This resin composition can be obtained by incorporating (A) a noncrystalline olefin resin with (B) microballoons like Silas balloons, calcium carbonate and any natural mineral matter such as tale, clay, etc., at a weight ratio A/B of (25:75) to (75:25) followed by hot compression molding or extrusion to any desired shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to, for example, synthetic wood,
TECHNICAL FIELD The present invention relates to a resin composition comprising an amorphous polyolefin resin and a micro hollow body, which is suitable as a material for a furniture material, an engraving material, a craft material, a heat insulating material, a soundproof material, etc. .

[0002]

2. Description of the Related Art Conventionally, as a resin composition comprising a thermosetting resin and a micro hollow body, for example, an unsaturated composition using a styrene vinyl monomer as a frame monomer and a micro hollow glass sphere as a filler. Polyester resin compositions are known.
This molded product is widely used in various applications such as synthetic wood, furniture materials, heat insulating materials, soundproofing materials, and buoyancy materials.

[0003]

However, this composition has a very bad odor, and there is a concern in terms of safety for human bodies such as processing workers. Also, a molded product made of this unsaturated polyester resin has a great defect that its commercial value is impaired due to its strong odor. Furthermore, if the functions such as lightness, heat insulation and soundproofing are emphasized, there is a fatal defect that the mechanical properties, especially the strength thereof, are remarkably lowered.

In order to overcome this drawback, various attempts have been made such as surface treatment of fine hollow bodies, addition of a reinforcing substance, improvement of the molding method, but none have been effective yet.

On the other hand, a resin composition comprising a crystalline polyolefin resin such as polyethylene, polypropylene and ethylene-vinyl acetate copolymer and a micro hollow body is tasteless and odorless and has no problem in health and safety. The melt viscosity of the product is too high, which makes molding by an ordinary resin molding method difficult.

Further, when the compounding amount of the resin is small, the mechanical properties of the obtained composition are remarkably low. On the contrary, when the compounding amount of the resin is large, the lightness and the heat insulating property which the obtained composition should have,
Not only are the advantages such as soundproofing lost, but they are also disadvantageous from an economical point of view.

[0007]

In the present invention, the amorphous polyolefin resin and the micro hollow body are mixed in a weight ratio of 25: 7.
The present invention provides a resin composition characterized in that it can be molded into an arbitrary shape by heat compression molding, extrusion molding or the like after mixing at a ratio of 5 to 75:25.

[0008]

The resin composition having the above-mentioned constitution can be used to obtain an arbitrary three-dimensional molded body by heat compression molding using a molding die or to obtain a plate-shaped molded body by extrusion molding. It is suitable for industrial materials, heat insulating materials, soundproofing materials, and other versatile materials.

[0009]

The present invention will be described below in a typical manner.

The resin composition according to the present invention comprises an amorphous polyolefin resin, shirasu balloon, calcium carbonate,
Small hollow bodies made of talf, clay and other natural mineral substances are mixed at a weight ratio of 25:75 to 75:25, and can be molded into any shape by heat compression molding or extrusion molding. Is.

The amorphous polyolefin resin is a homopolymer, a binary copolymer or a multicomponent copolymer selected from ethylene, propylene and α-olefins having 4 to 8 carbon atoms.

Particularly preferably, a propylene homopolymer, a propylene / ethylene copolymer, a propylene / butene-1 copolymer, or a propylene / ethylene.
An amorphous polyolefin resin containing a propylene component such as a terpolymer of butene-1 or a butene-1 component as a main component can be used.

The amorphous polyolefin resin is the lightest of the polyolefin resins, having a solid specific gravity of 0.85 to 0.95 g / cm ^{3 as} a simple substance, and an elastic modulus of 5 at room temperature.
Since it is very flexible at 0 to 500 kg / cm ² , it is an optimal material for applications requiring light weight and secondary workability.

The amorphous polyolefin resin is 150
Since the viscosity at the time of melting at up to 250 ° C. is very low such as hundreds to tens of thousands centipoise, even a resin composition obtained by mixing a large amount of micro hollow bodies with this amorphous polyolefin resin is a normal resin. It has a characteristic that it can be molded into an arbitrary shape by a heat compression molding or an extrusion molding which is a molding method.

The micro hollow bodies referred to in the present invention are, for example, glass micro balloons, shirasu balloons, pearlite,
It is an inorganic fired foam mainly composed of silicate, such as silica balloon, and has a shape of minute hollow sphere. The particle size (particle size) of these micro hollow bodies is generally preferably 50 to 300 μm.

The blending ratio of the amorphous polyolefin resin and the micro hollow body is generally a weight ratio of amorphous polyolefin resin: micro hollow body = 25: 75 to 75:25, preferably 35:65 to 65: 35. If the blending amount of the amorphous polyolefin resin is less than the above range, the mechanical properties of the resulting composition, particularly the strength, are deteriorated. Further, when the amount of the amorphous polyolefin resin is large, not only the advantages such as lightness, heat insulation and soundproofing that the composition should have are lost, but also it is disadvantageous from the economical aspect.

When mixing the amorphous polyolefin resin and the micro hollow body, it can be easily carried out by a mixing stirrer such as a kneader or a mixer. At this time, the temperature of the stirrer is 1
It is suitable to maintain the temperature at 50 to 250 ° C. and the mixing time is about 15 minutes.

After sufficient mixing and stirring, the resin composition may be supplied to the next molding step while being heated and kept warm.
It is also possible that the material is once cooled and solidified, pulverized into particles or an appropriate size, and then stored until the next molding.

The molding method is not particularly limited, but it is most preferable to employ heat compression molding or extrusion molding.
When using heat compression molding, the molding pressure is 10 to 30 kg /
It is preferably about cm ² . If the molding pressure is too high,
The micro hollow body may be destroyed. Molding conditions such as temperature and time vary depending on the size and shape of the molded product, but generally a pressure time of 5 to 30 minutes at a temperature of 150 to 250 ° C. is suitable.

The thickness of the molded body is not particularly limited, but is preferably 5 mm or more. 5mm thick
When it is below, the strength of the molded product is low and it becomes difficult to handle in practical use.

In addition, fillers such as calcium carbonate, kaolin, talc, barium sulfate, calcium sulfate, glass powder and wood powder, and glass fibers, synthetic fibers, metal fibers, carbon fibers and the like can be used as long as the effects of the present invention are not lost. Materials generally used for polyolefin resin compositions such as fiber reinforcing materials, thermoplastic resins such as polyethylene and polypropylene, lubricants, pigments, colorants, and release agents may be added appropriately.

Of these, the filler has a role of adjusting the specific gravity of the molded product, and is added in an appropriate amount to give a feeling of weight to the molded product.

The present invention will be further described with reference to Examples and Comparative Examples. However, the present invention is not limited to the following examples.

[0024]

Example 1 As an amorphous polyolefin resin, 60% of a propylene / ethylene copolymer (manufactured by Ube Lexen: trade name "Ubetack" UT2215) was used, and as a micro hollow body, Shirasu balloon ("Windlight" manufactured by Ichikasei Co., Ltd.). "
40% by weight of WB-601) was stirred and mixed with a kneader in a heating atmosphere at 200 ° C. The obtained composition was press-compressed and molded at 180 ° C. and a temperature of 20 kg / cm ² for 10 minutes under a pressure of 220 × 220 × thickness 10 (m
A plate-shaped molded product of m) was obtained. The evaluation results are shown in Table 1.

[0025]

[Table 1]

[0026]

Example 2 As Example 1 except that 60% by weight of a copolymer of propylene / butene-1 (manufactured by Ube Lexen Co., Ltd .: trade name “Ubetack” UT2715) was used as the amorphous polyolefin resin. A plate-shaped molded body was obtained in the same manner. The evaluation results are shown in Table 1.

[0027]

Comparative Example 1 Example 1 was repeated except that 40% by weight of ethylene-vinyl acetate copolymer (EVA "V319" manufactured by Ube Industries, Ltd.) was used as the crystalline polyolefin instead of the amorphous polyolefin resin. A plate-shaped molded body was obtained in the same manner as. The evaluation results are shown in Table 1.

In the above table, the secondary workability is judged by ○ when the molded product is cut with a chisel, the chips are arcuate and the sharpened corners are firm and have hardness suitable for engraving. Those that are not are marked with x.

[0029]

EFFECTS OF THE INVENTION The resin composition of the present invention is lightweight and excellent in secondary workability because it is made by mixing the amorphous polyolefin resin and the micro hollow body. To obtain a three-dimensional molded body, or a plate-shaped molded body by extrusion molding, to obtain synthetic wood, furniture materials, engraving materials,
It is suitable for industrial materials, heat insulating materials, soundproofing materials, and other versatile materials, and has the practical effects of achieving the object of the invention.

Claims (1)

[Claims] 1. A non-crystalline polyolefin resin is mixed with a micro hollow body made of shirasu balloon, calcium carbonate, talf, clay or any other natural mineral substance at a weight ratio of 25:75 to 75:25. A resin composition, which can be molded into an arbitrary shape by heat compression molding, extrusion molding, or the like.