JPH0517632A - Highly filled inorganic resin composition and method for producing the same - Google Patents

Abstract

(57) [Summary] [Purpose] The lubrication properties at the interface between the highly filled inorganic powder and the polyolefin resin and the tackiness of the polymer are improved to improve workability and prevent bleed-out of the lubrication component. Moreover, to provide a modified inorganic highly filled resin composition. [Structure] An inorganic highly filled composition containing a polyolefin resin, an inorganic powder and a silicone oil having a functional group at one or both ends. A method for producing an inorganic highly-filled composition, which comprises chemically crosslinking or irradiating and crosslinking the composition with ionizing radiation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inorganic highly-filled composition, and more particularly to an inorganic highly-filled polyolefin resin composition suitable for a construction material field represented by folded plates and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, it is a known technique to use a composition obtained by filling a polyolefin resin with an inorganic powder in a field where flame retardancy is required such as a building material (Japanese Patent Publication No. 62-16217). JP-B-56-51181, JP-A-59-81345, JP-A-1-126346.
issue). In these conventional techniques, there is also an example in which a polyolefin resin is highly filled with an inorganic powder to obtain flame retardancy, and a flame retardant is added to improve the flame retardant effect.
Further, a cross-linking foam can be prepared by adding a foaming agent to these inorganic filling compositions.

By the way, when a low crystalline resin such as ethylene-vinyl acetate copolymer (EVA) is used as the polyolefin resin for high filling of the inorganic powder, the polymer is sticky, and the processing is difficult. is there. Further, even if ultra-low density polyethylene (VLDPE) is used, the composition with high lubricity becomes relatively inferior, and thus the processing is still not easy. In addition, the highly filled composition has a large torque load during kneading due to the oil absorption of the filled material. Therefore, when silicone oil is added to reduce tackiness and torque during kneading, the silicone oil bleeds out on the surface of the resin composition in a short time, and it is as if the silicone oil was applied to the surface. Silicone oil film is generated. This bleed-out silicone oil film adheres and contaminates when it comes into contact with other substances. Moreover, the appearance of the molded product is impaired due to the bleed-out of the silicone oil.

On the other hand, it has been proposed to add an organopolysiloxane polymer to a polyolefin resin composition highly filled with an inorganic powder (Japanese Patent Publication No. 59-301).
No. 78). It is expected that the addition of the organopolysiloxane polymer will improve the lubrication characteristics at the interface between the inorganic powder and the polyolefin resin and the lubricity of the molded product, but the torque at the initial stage of melt kneading will be excessive and the processing There is difficulty in sex. Organopolysiloxane polymers have poor compatibility with polyolefin resins and require a long time for kneading in order to be highly dispersed.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to improve the lubrication characteristics at the interface between the highly filled inorganic powder and the polyolefin resin and the tackiness of the polymer to improve the processability, and to improve the lubrication component. Another object of the present invention is to provide a modified inorganic highly-filled resin composition which prevents the bleeding out of the resin.

The present inventors have conducted extensive studies to overcome the above-mentioned problems of the prior art, and as a result, as a lubrication-imparting component,
It has been found that by using a silicone oil having a functional group at one end or both ends, the torque during kneading can be reduced and the dispersibility of the filler and the resin can be improved. Further, bleed-out of the silicone oil can be prevented and physical properties of the resin composition can be improved by performing chemical crosslinking or irradiation crosslinking with ionizing radiation. The present invention has been completed based on these findings.

[0007]

According to the present invention, (a)
An inorganic highly filled composition containing 100 parts by weight of a polyolefin resin, (b) 50 to 500 parts by weight of an inorganic powder, and (c) 0.1 to 15 parts by weight of a silicone oil having a functional group at one or both ends. Provided.

Further, according to the present invention, (a) 100 parts by weight of a polyolefin resin, and (b) 50 to 5 inorganic powders.
100 parts by weight and (c) 0.1 to 15 parts by weight of a silicone oil having a functional group at one or both ends, and then chemically crosslinking or irradiation crosslinking with ionizing radiation. A method of making a filling composition is provided.

The present invention will be described in detail below. The silicone oil used in the present invention is a dimethyl polysiloxane represented by the following general formula [1] or [2] having a reactive functional group at one or both ends.

[0010]

[0011]

In the above general formulas [1] and [2], R represents a functional group, specifically, a methacryl group, a carbinol group, an amino group, a carboxyl group, an epoxy group, a mercapto group, a phenol group or the like. Can be mentioned. Among these functional groups, a methacrylic group is preferable.

When a silicone oil having a functional group is added to the resin composition, a part thereof functions as an external lubricant and the remaining part is present at the interface between the inorganic powder and the resin to provide lubricity. Further, compared with the case where the organopolysiloxane polymer is added, it is advantageous in terms of torque and dispersion, and the sliding effect can be obtained.

Further, when the resin composition is chemically crosslinked or irradiated with an ionizing radiation (electron beam, α-ray, β-ray, γ-ray, etc.) to be crosslinked, bleed-out of the silicone oil, which is a conventional problem, can be prevented. In addition to the above properties, the functions of the resin composition (impact resistance, flexibility, water repellency, etc.) can be improved. It is presumed that the bleed-out is prevented because the functional group of the silicone oil having a functional group is bonded to, for example, the main chain or side chain of the polymer in these crosslinking steps.

The silicone oil having a functional group is added in an amount of 0.1 to 15 parts by weight based on 100 parts by weight of the polyolefin resin. If it is less than 0.1 part by weight, the effect of imparting lubricity is small, and if it exceeds 15 parts by weight, the physical properties of the resin composition deteriorate.

The polyolefin resin used in the present invention is, for example, polyethylene (low density, medium to high density, linear low density, VLDPE), ethylene-vinyl acetate copolymer (EVA), ethylene-acryl. Ethyl acid copolymer, ethylene-acrylic acid copolymer, ethylene-α
-Olefin copolymer, polypropylene, propylene-
Butene copolymers, ethylene-propylene copolymers, and mixtures thereof can be mentioned.

Examples of the inorganic powder include aluminum hydroxide, magnesium hydroxide, calcium hydroxide, barium hydroxide, tin oxide hydrate, basic magnesium carbonate, hydrotalcite, heart crew, talc and mica. Examples thereof include hydrated metal oxides and mixtures thereof. The blending ratio of the inorganic powder is 50 to 500 parts by weight, preferably 50 to 350 parts by weight, based on 100 parts by weight of the polyolefin resin. If it is less than 50 parts by weight, the flame retarding effect due to the addition of the inorganic powder is small, and if it exceeds 500 parts by weight, moldability and physical properties are deteriorated.

A flame retardant and a flame retardant aid may be appropriately added to the composition of the present invention to impart higher flame retardancy.
Examples of the flame retardant include decabromodiphenyl ether, pentabromochlorocyclohexane, hexabromocyclododecane, 2,3,5,6-pentabromoethylbenzene, 1,2-bis (2,4,5-tribromophenoxy) ethane. , Halogenated flame retardants such as chlorinated paraffin, hexachloropentacyclodecane, hexabromobenzene, and tetrabromobisphenol A / derivative. Examples of the flame retardant aid include antimony trioxide, sodium antimonate, tin oxide, red phosphorus and the like. When using these flame retardants, the amount is usually 3 to 30 parts by weight, preferably 5 to 25 parts by weight, based on 100 parts by weight of the polyolefin resin. When the flame retardant aid is used, it is usually 1 to 20 parts by weight, preferably 2 to 15 parts by weight, based on 100 parts by weight of the polyolefin resin.

A foaming agent may be added to the composition of the present invention to carry out chemical crosslinking or ionizing radiation irradiation crosslinking, and heat-foamed to obtain a foam.

[0020]

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

[Example 1] 5 parts by weight of trimethylpolysiloxane having a methacryl group at one end, based on 100 parts by weight of commercially available polyethylene (density 0.923, MI = 2.0) and 100 parts by weight of magnesium hydroxide. Was added.
This composition was sufficiently kneaded with two rolls heated to 130 ° C., and then press-formed into a plate having a thickness of 3 mm. On the other hand, for comparison, a plate-shaped molded product was prepared in the same manner as above except that the silicone oil having a functional group was not added.

Observation of the surfaces of the obtained two kinds of plate-shaped molded products revealed that the one to which the functional group-containing silicone oil was added was very beautiful.

Example 2 Polyethylene (density 0.92
3, MI = 2.0) 100 parts by weight and magnesium hydroxide 100 parts by weight, 5 parts by weight of trimethylpolysiloxane having a methacryl group at one end is added, roll-mixed, and hot pressed to form a plate. I created a thing. This plate-shaped molded product was irradiated with an electron beam at a dose of 5 Mrad. On the other hand, for comparison, a plate-shaped molded product was obtained in the same manner as above except that trimethylpolysiloxane having no functional group was added, and similarly irradiated with an electron beam.

In the plate-shaped molded article to which trimethylpolysiloxane having no functional group was added, a silicone oil layer as if silicone oil was applied to the surface was clearly observed after 48 hours, but a methacrylic group was formed at one end. No such bleed-out was observed in the plate-shaped moldings added with trimethylpolysiloxane having s.

Example 3 Ethylene-vinyl acetate copolymer (density 0.94, vinyl acetate content 25% by weight) 10
0 parts by weight and 100 parts by weight of magnesium hydroxide,
5 parts by weight of trimethylpolysiloxane having a methacryl group at one end was added, and the mixture was kneaded with two rolls heated to 130 ° C. On the other hand, for comparison, and kneading with a two-roll mill in the same manner as above except that the silicone oil having a functional group was not added.

The composition to which the silicone oil having a functional group was added could be easily kneaded, but the composition to which the silicone oil was not added adhered to the roll during kneading and was difficult to mold.

When the kneading operation was performed with a 3 liter kneader mixer instead of the two rolls, the composition to which the silicone oil having a functional group was added could be easily kneaded. The missing composition was difficult to discharge due to sticking to the casing during kneading.

[0028]

EFFECTS OF THE INVENTION According to the present invention, it is possible to provide a resin composition having improved interfacial properties between an inorganic powder and a resin and improved lubricity of a molded product. Further, by crosslinking, bleed-out of silicone oil can be prevented and the resin composition can be modified.

Claims (2)

[Claims] 1. (a) 100 parts by weight of a polyolefin resin, (b) 50 to 500 parts by weight of an inorganic powder, (c) a silicone oil having a functional group at one or both ends.
An inorganic highly-filled composition containing 1 to 15 parts by weight. 2. (a) 100 parts by weight of a polyolefin resin, (b) 50 to 500 parts by weight of inorganic powder, and (c)
A method for producing an inorganic highly-filled composition, comprising adding 0.1 to 15 parts by weight of a silicone oil having a functional group at one end or both ends, and then crosslinking by irradiation with chemical crosslinking or ionizing radiation.