JPH0733458B2 - Chlorinated polyethylene resin composition - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a chlorinated polyethylene resin composition. More specifically, it relates to a chlorinated polyethylene resin composition having excellent heat aging resistance.

[0002]

2. Description of the Related Art Conventionally, wiring materials for various electric and electronic devices,
For heat resistant wires such as motor lead wires and transformer lead wires,
As the insulating coating material, a heat-resistant and flame-retardant vinyl chloride resin composition and a flame-retardant cross-linked polyethylene resin composition containing a halogen-based flame retardant are used. It is difficult to maintain the characteristics,
The latter has a problem of environmental pollution due to the halogen-based flame retardant compounded. On the other hand, in recent years, with the downsizing of equipment and the increase in capacity of energizing current, there is a demand for insulating coating materials with even more excellent heat resistance and flame retardance. is there.

[0003]

DISCLOSURE OF THE INVENTION The present invention has excellent heat aging resistance, and is therefore preferably used as a coating material for various electric wires which are required to have heat resistance and flame retardancy. It is intended to provide a resin composition.

[0004]

Means for Solving the Problems As a result of repeated studies to achieve the above object, the present inventors have found that a chlorinated polyethylene having a specific chlorine content and having a specific crystallinity, It has been found that a resin composition suitable for the above purpose can be obtained by blending lead silicate produced by a specific method as a stabilizer with the present invention. That is, the gist of the present invention is to use lead oxide as a stabilizer with respect to 100 parts by weight of chlorinated polyethylene having a chlorine content of 15 to 30% by weight and a crystal residue of 5 to 15 cal / g by a differential scanning calorimetry. A chlorinated polyethylene resin composition is characterized by comprising 3 to 50 parts by weight of lead silicate obtained by melting and cooling and pulverizing a mixture with silicon dioxide.

The present invention will be described in detail below. The chlorinated polyethylene used in the composition of the present invention must have a chlorine content of 15 to 30% by weight. When the chlorine content is less than 15% by weight, there is a problem in production such that the composition adheres to a vessel wall or a stirrer during kneading of the composition, and it is difficult to impart excellent flame retardancy. On the other hand, if the chlorine content exceeds 30% by weight, a product having excellent heat resistance cannot be obtained. A particularly preferable chlorine content is 15 to 25% by weight.

The chlorinated polyethylene in the present invention also has a differential scanning calorimetry (DSC method, differen).
tial scanning calorimetr
It is necessary that the crystal residue due to y) is 5 to 15 cal / g. When the crystal residue according to the DSC method is less than 5 cal / g, good initial physical properties as a coating material cannot be obtained, while when it is more than 15 cal / g, excellent heat resistance cannot be obtained. Particularly preferred is chlorinated polyethylene having a crystal residue of 5 to 15 cal / g. The differential scanning calorimetry method (DSC method) is known as a general method for measuring the crystallinity of a polymer.

The composition of the present invention comprises the above chlorinated polyethylene and a lead silicate obtained by melting and cooling and pulverizing a mixture of lead oxide and silicon dioxide as a heat stabilizer. For example, lead silicate obtained by the coprecipitation method is unsuitable. The amount of lead silicate used is required to be 3 to 50 parts by weight, and particularly preferably 5 to 20 parts by weight, based on 100 parts by weight of chlorinated polyethylene. When the amount of lead silicate used is less than 3 parts by weight, the heat stabilizing effect of the composition is insufficient, and even if more than 50 parts by weight is used, the heat stabilizing effect is not further improved, and the tensile strength is increased. However, the elongation and the like decrease, which is not preferable.

In addition to the above essential components, the composition of the present invention further comprises metal oxides such as antimony trioxide and antimony pentoxide, tetrabromobisphenol A, hexabromobenzene, in order to further improve flame retardancy. Brominated and chlorinated organic substances such as chlorinated paraffin, and well-known heat stabilizers such as tribasic lead sulfate, dibasic lead stearate, dibasic lead phosphite, and basic lead sulfite are used together. Alternatively, a vinyl chloride resin may be blended with the resin component. Furthermore, if necessary, various well-known additives such as 1,
1,3-tris- (2-methyl-4-hydroxy-5-
Phenolic antioxidants such as t-butylphenyl) butane, tetrakis- [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, di-t-butylperoxide Oxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3 Etc., a crosslinking aid such as trimethylolpropane triacrylate, a lubricant, an ultraviolet absorber, a filler, a colorant and the like can be used in combination. In addition, for example, the resin component may be crosslinked by irradiation with ionizing radiation or addition of a peroxide.

To prepare the chlorinated polyethylene resin composition of the present invention, the above-mentioned chlorinated polyethylene, lead silicate and, if necessary, the above-mentioned additives are mixed in predetermined proportions, respectively, and then a ribbon blender and a cake are prepared. Disperse uniformly using a mixer, high-speed mixer, etc., and then use a mill roll, Banbury mixer, pressure kneader, single-screw extruder, twin-screw kneading extruder, plasticizer, cokneader, etc. After kneading at temperature, pelletize,
It may be formed into a desired shape.

[0010]

EXAMPLES Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to the following examples unless it exceeds the gist thereof. In the following Examples and Comparative Examples, “parts” and “%” represent “parts by weight” and “% by weight”, respectively, unless otherwise specified.

Example 1 100 parts of chlorinated polyethylene having a chlorine content of 22% and a crystal residue by DSC method (hereinafter, simply referred to as crystal residue) of 7 cal / g, and a mixture of lead oxide and silicon dioxide were melted and cooled. 20 parts of lead silicate obtained by crushing was mixed, and 10 parts of antimony trioxide, 2 parts of dibasic lead stearate, tetrakis- [methylene-3- (3 ', 5'-di-t-butyl- 4'-hydroxyphenyl) propionate] methane (phenolic antioxidant) 2 parts, trimethylolpropane triacrylate (crosslinking aid) 10 parts and 2,5-dimethyl-2,5-di (t-butylperoxy) 2.0 parts of hexane (crosslinking agent) was blended, uniformly dispersed using a ribbon blender, and then kneaded with a mill roll to form pellets.

The pellets obtained above were kneaded with a 9-inch mill roll at 150 to 170 ° C. for 7 minutes to obtain a sheet having a thickness of about 0.3 mm. Then, several sheets of this sheet are stacked and press-molded at 200 kg / cm ² through a mirror press plate between hot plates at 180 to 200 ° C. to form a bridge having a thickness of 1 mm.
A dumbbell-shaped test piece was prepared. For this test piece,
A heat aging test is performed in accordance with JIS K-6723, and the elongation residual ratio is 158 ° C. × 168 hrs and 175 ° C.
It was measured under the condition of 168 hrs, and the degree of coloring was measured by visual judgment. The results are shown in Table 1.

Example 2 The same compounding ingredients as in Example 1 were used in the same amounts as in Example 1 except that the amount of lead silicate used in Example 1 was changed to 10 parts. A test piece was prepared by mixing, kneading and press-molding in exactly the same manner as in. The obtained test piece was subjected to a heat aging test by the method of Example 1 to measure the residual elongation and the degree of coloring, and the results are shown in Table 1.

Example 3 Except that the amount of lead silicate used in Example 1 was changed to 5 parts,
The same compounding ingredients as in Example 1 were used in the same amounts as in Example 1, respectively, and mixing, kneading and press molding were performed in exactly the same manner as in Example 1 to prepare test pieces. About the obtained test piece,
A heat aging test was conducted by the method of Example 1, the residual elongation and the degree of coloring were measured, and the results are shown in Table 1.

Example 4 The same compounding ingredients as in Example 1 were used, except that the amount of lead silicate used in Example 1 was 5 parts and 5 parts of tribasic lead sulfate was added. Using the same amount, mixing, kneading, and press molding were performed in the same manner as in Example 1 to prepare a test piece. The obtained test piece was subjected to a heat aging test by the method of Example 1 to measure the residual elongation and the degree of coloring, and the results are shown in Table 1.

Example 5 Instead of the chlorinated polyethylene used in Example 1, 100 parts of chlorinated polyethylene having a chlorine content of 23% and a crystal residue of 15 cal / g was used, and the amount of lead silicate used was 10%. The same components as in Example 1 were used in the same amounts as in Example 1 except for the parts, and the test pieces were prepared by mixing, kneading and press-molding in exactly the same manner as in Example 1. The obtained test piece was subjected to a heat aging test by the method of Example 1 to measure the residual elongation and the degree of coloring, and the results are shown in Table 1.

Example 6 Instead of the chlorinated polyethylene used in Example 1, 100 parts of chlorinated polyethylene having a chlorine content of 30% and a crystal residue of 15 cal / g was used, and the amount of lead silicate used was 10. The same components as in Example 1 were used in the same amounts as in Example 1 except for the parts, and the test pieces were prepared by mixing, kneading and press-molding in exactly the same manner as in Example 1. The obtained test piece was subjected to a heat aging test by the method of Example 1 to measure the residual elongation and the degree of coloring, and the results are shown in Table 1.

Example 7 The lead silicate used in Example 1 was used in an amount of 10 parts, and 2,5-dimethyl-2,5-di (t-butylperoxy) hexane (crosslinking agent) was not used. Other than the above, the same compounding ingredients as in Example 1 were used in the same amounts as in Example 1, respectively, and mixing, kneading and press molding were performed in exactly the same manner as in Example 1 to prepare test pieces. 10 Mrad was added to the obtained test piece.
After irradiating with radiation to perform crosslinking treatment, a heat aging test is performed by the method of Example 1 to measure the residual elongation and the degree of coloring,
The results are shown in Table 1.

[0019]

[Table 1]

As shown in Table 1, 158 ° C. × 168 hours
In the heat aging test under the condition of s, all of the compositions of the present invention of Examples 1 to 6 show a high elongation residual ratio of 60% or more and a low coloring degree. Especially, chlorine content is about 20% and crystal residue is 7
The composition of the present invention in which 5 to 20 parts of lead silicate is mixed with 100 parts of cal / g chlorinated polyethylene (Examples 1 to 1)
It is recognized that the elongation residual ratio of 4) is 90% or more, and the degree of coloring is extremely small. Also, 175 ° C x 168 hr
Also in the heat aging test under the condition of s, the compositions of Examples 1 to 4 showed a residual elongation ratio of 65% or more, showing that the compositions can be used under high temperature conditions. Example 5,
In No. 6, the elongation residual ratio is slightly low, but the effect of adding lead silicate is sufficiently observed.

Comparative Example 1 Instead of the chlorinated polyethylene used in Example 1, 100 parts of chlorinated polyethylene having a chlorine content of 40% and a crystal residue of 15 cal / g was used, and the amount of lead silicate used was 10. The same components as in Example 1 were used in the same amounts as in Example 1 except for the parts, and the test pieces were prepared by mixing, kneading and press-molding in exactly the same manner as in Example 1. The obtained test piece was subjected to a heat aging test by the method of Example 1 to measure the residual elongation and the degree of coloring, and the results are shown in Table 2.

Comparative Example 2 Instead of the chlorinated polyethylene used in Example 1, 100 parts of chlorinated polyethylene having a chlorine content of 35% and a crystal residue of 5 cal / g was used, and the amount of lead silicate used was 10%. Except that the same components as in Example 1 were used,
Used in the same amount as above and mixed exactly as in Example 1 below,
A test piece was prepared by kneading and press molding. The obtained test piece is subjected to a heat aging test by the method of Example 1,
The residual elongation and the degree of coloring were measured, and the results are shown in Table 2.

Comparative Example 3 Instead of the chlorinated polyethylene used in Example 1, 100 parts of chlorinated polyethylene having a chlorine content of 30% and a crystal residue of 1 cal / g or less was used, and the amount of lead silicate used was changed. 10
The same components as in Example 1 were used in the same amounts as in Example 1 except for the parts, and the test pieces were prepared by mixing, kneading and press-molding in exactly the same manner as in Example 1. The obtained test piece was subjected to a heat aging test by the method of Example 1 to measure the residual elongation and the degree of coloring, and the results are shown in Table 2.

Comparative Example 4 Instead of the chlorinated polyethylene used in Example 1, 100 parts of chlorinated polyethylene having a chlorine content of 23% and a crystal residue of 15 cal / g was used, and lead silicate was not used. The same compounding ingredients as in Example 1 were used in the same amounts as in Example 1 except that 10 parts of tribasic lead sulfate was used instead, and mixing, kneading and press molding were performed in exactly the same manner as in Example 1. Then, a test piece was prepared. The obtained test piece was subjected to a heat aging test by the method of Example 1 to measure the residual elongation and the degree of coloring, and the results are shown in Table 2.

Comparative Example 5 In place of the chlorinated polyethylene used in Example 1, 100 parts of chlorinated polyethylene having a chlorine content of 23% and a crystal residue of 1 cal / g was used, and lead silicate was not used, Example 1 except that 10 parts of dibasic lead phthalate was used instead.
Using the same compounding ingredients as in Example 1 in the same amounts as in Example 1,
In the same manner as in Example 1 below, a test piece was prepared by mixing, kneading and press molding. About the obtained test piece, Example 1
The heat aging test was carried out by the method of No. 1, and the elongation residual ratio and the coloring degree were measured, and the results are shown in Table 2.

Comparative Example 6 Instead of the chlorinated polyethylene used in Example 1, 100 parts of chlorinated polyethylene having a chlorine content of 23% and a crystal residue of 15 cal / g was used, and the amount of lead silicate used was 2%. Except that the same components as in Example 1 were used,
Used in the same amount as above and mixed exactly as in Example 1 below,
A test piece was prepared by kneading and press molding. The obtained test piece is subjected to a heat aging test by the method of Example 1,
The residual elongation and the degree of coloring were measured, and the results are shown in Table 2.

[0027]

[Table 2]

As shown in Table 2, when the chlorine content or crystal residue of the chlorinated polyethylene is out of the range of the present invention (Comparative Examples 1 to 3), or lead silicate is not used (Comparative Examples 4 to 5). Even when used, if the amount used is outside the range specified in the present invention (Comparative Example 6), the elongation residual ratio of the composition is extremely low and remarkable even in the heat aging test under the condition of 158 ° C. × 168 hrs. Coloring is observed, 175 ° C x 168hr
Under the condition of s, it is clear that the heat aging property is further deteriorated.

[0029]

As described above, since the chlorinated polyethylene resin composition of the present invention has excellent heat aging resistance,
It is extremely suitable as a coating material for various heat-resistant electric wires and the like that require heat resistance and flame retardancy.

Claims (1)

[Claims] 1. The chlorine content is 15 to 30% by weight,
5-15 cal / g of crystal residue by differential scanning calorimetry
3 to 50 parts by weight of lead silicate obtained by melting and cooling and pulverizing a mixture of lead oxide and silicon dioxide as a stabilizer with 100 parts by weight of chlorinated polyethylene. Polyethylene resin composition.