JPH09278947A - Flame-retardant polyolefin resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition capable of synergistically improving flame-retardant effects and tensile properties and reducing the amount of flame retardant added by blending a polyolefin with melamine phosphate and ethylenediamine phosphate. SOLUTION: This flame-retardant polyolefin resin composition is obtained by blending (A) 100 pts.wt. of a polyolefin (e.g. low-density polyolefin or polypropylene) with (B) 3-30 pts.wt. of melamine phosphate and (C) 3-30 pts.wt. of ethylenediamine phosphate as a flame retardant. The total of the components B and C is preferably 6-40 pts.wt. based on 100 pts.wt. of the component A. The blending ratio of the components B and C is preferably 80:20 to 20:80 (weight ratio). A melamine phosphate having 10-30 wt.% phosphorus content and 30-50wt.% nitrogen content is preferable in terms of flame retardance and physical properties of resin. The component C is generally obtained by reacting equimolar amounts of ethylenediamine and phosphoric acid in an aqueous solution.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a flame-retardant polyolefin composition having a low content of a halogen-free flame retardant which is excellent in flame retardancy and resin properties.

[0002]

2. Description of the Related Art Conventionally, halogen-based flame retardants have been widely used as flame retardants for polyolefins because of their excellent flame retardancy, resin properties, and price. The generation of toxic gas at the time became problematic,
In recent years, conversion to a method of achieving flame retardance without using a halogen-based compound is progressing. As a non-halogen flame retardant,
Inorganic hydroxides such as magnesium hydroxide, nitrogen-based compounds such as isocyanuric acid, and phosphorus-based compounds such as red phosphorus and triphenyl phosphate are known.

On the other hand, as a flame retardant containing nitrogen and phosphorus, ammonium polyphosphate, melamine phosphate,
Ethylenediamine phosphate and the like are known. As examples of blending melamine phosphate with polyolefin, there are JP-A-56-18634 and JP-A-7-258479, both of which are used in combination with a metal hydroxide. Further, the blending of ethylenediamine phosphate with polyolefin is disclosed in Japanese Patent Publication No. 5-505409.

[0004]

In flame-retarding a polyolefin with an inorganic hydroxide such as magnesium hydroxide, a large amount of compound is required to obtain a flame-retardant effect, resulting in deterioration of resin physical properties, especially tensile physical properties. However, there is a problem that the decrease in Further, with respect to the nitrogen-based compound, it is difficult to obtain the flame-retardant effect by itself, and there is a problem that the number of parts to be added is increased or the combined use with the phosphorus-based compound cannot be avoided. Furthermore, red phosphorus may generate toxic phosphine due to heat during processing or fire.

On the other hand, when melamine phosphate is used alone, it is difficult to obtain flame retardancy, and when it is used in a larger amount, the workability during molding is greatly reduced, or the physical properties of the resin are significantly reduced. . Further, although ethylenediamine phosphate has a flame retardant effect, it requires a higher compounding amount as compared with a halogen-based flame retardant, so that there is a problem that deterioration of mechanical properties and deterioration of water resistance cannot be avoided. .

The present invention has been made in view of the above problems, and an object thereof is to show excellent flame retardancy even in a flame retardant containing no halogen-based compound at a low compounding amount, and further, a low flame retardant compounding. It is an object of the present invention to provide a flame-retardant polyolefin composition having improved resin properties, particularly tensile properties, depending on the composition.

[0007]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have surprisingly found that the combined use of melamine phosphate and ethylenediamine phosphate has a synergistic flame retardant effect. It has been found that the flame retardancy of polyolefin can be achieved with a low compounding amount, and the present invention has been completed.

That is, the present invention relates to polyolefin 100
It is a flame-retardant polyolefin composition obtained by blending 3 to 30 parts by weight of melamine phosphate and 3 to 30 parts by weight of ethylenediamine phosphate as a flame retardant with respect to parts by weight.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.

The polyolefin used in the present invention contains ethylene, propylene, and other olefinic monomers as main components, and is not particularly limited. Specifically, low-density polyethylene, high-density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-α-olefin copolymer, α-olefin-
Butadiene copolymer, ethylene-vinyl acetate copolymer,
Examples thereof include ethylene-acrylic acid ester copolymers and ethylene-methacrylic acid ester copolymers. Examples of the acrylate copolymerized with ethylene or the like include methyl acrylate and ethyl acrylate, and examples of the methacrylate include methyl methacrylate and ethyl methacrylate. These resins may be used alone or in combination of two or more.

The melamine phosphate used in the present invention is not particularly limited, and a commercially available product can be used as it is. The phosphorus content and the nitrogen content in melamine phosphate are not particularly limited, but the phosphorus content is 10 to 30% and the phosphorus content is 30 to 50%.
It is preferable that the nitrogen content is within the range from the viewpoint of flame retardancy and resin physical properties.

The ethylenediamine phosphate used in the present invention is not particularly limited, and a commercially available product can be used as it is. This ethylenediamine phosphate is obtained by reacting ethylenediamine and phosphoric acid in an equimolar amount of an aqueous solution.

In the present invention, the blending amounts of melamine phosphate and ethylenediamine phosphate used as flame retardants vary depending on the type of resin to be blended and the intended flame retardant performance. It is in the range of 3 to 30 parts by weight, and preferably the total amount of melamine phosphate and ethylenediamine phosphate is in the range of 6 to 40 parts by weight with respect to 100 parts by weight of the polyolefin. If the total amount of melamine phosphate and ethylenediamine phosphate is less than 6 parts by weight, sufficient flame retardancy cannot be imparted. If the total amount exceeds 40 parts by weight, the resin properties of the flame-retardant polyolefin composition, which is the object of the present invention, may not be improved. As an effect of the present invention, as compared with the case where the polyolefin is flame-retarded with ethylenediamine phosphate alone, even if the amount of the flame retardant compounded is reduced by about 30 to 60% with respect to 100 parts by weight of the polyolefin, the same flame retardancy is obtained. Performance is obtained.

In the present invention, the blending ratio of melamine phosphate and ethylenediamine phosphate is 80: 20-2.
It is preferably in the range of 0:80 (weight ratio). When the amount of melamine phosphate in the flame retardant is less than 20% by weight, it is difficult to obtain the so-called combined effect which is the object of the present invention, and in order to obtain the same flame retardant effect, the same blending amount as in the case of ethylenediamine phosphate alone. May be required. On the other hand, when the amount of melamine phosphate in the flame retardant exceeds 80% by weight,
The required blended amount may increase significantly, and even if the blended amount is increased, the required flame retardant effect may not be obtained.

The flame-retardant polyolefin composition of the present invention may further contain, if necessary, other compounding agents such as inorganic fillers such as talc, mica, calcium carbonate and the like, glass fibers, carbon fibers and the like. Agents, ultraviolet absorbers, light stabilizers, antioxidants, antistatic agents, pigments, release agents, impact modifiers and the like can be added.

The method for producing the flame-retardant polyolefin composition of the present invention is not particularly limited, but for example,
Polyolefin, melamine phosphate, ethylenediamine phosphate and, if necessary, other reagents are mixed using a conical blender, a tumbler mixer, etc., pelletized using a twin-screw extruder, etc., and the obtained pellets are extruded and injected. The desired molded article can be obtained by performing molding or the like.

Applications of the flame-retardant polyolefin composition of the present invention include coating materials for electric wires / cables, metal pipes, household electrical appliances, various sheets and the like.

[0018]

The flame-retardant polyolefin composition of the present invention requires only a small amount of a flame-retardant compound to obtain the required flame-retardant effect. It is possible to improve the deterioration of the physical properties of the resin, particularly the deterioration of the tensile properties.

[0019]

EXAMPLES The present invention will now be specifically described with reference to examples, but the present invention is not limited to the examples.

The evaluation as a flame-retardant resin composition was carried out by the following method.

(Combustion test) The oxygen index was measured according to JIS-K-7201, and the UL combustion test was performed according to the UL94V vertical flammability test.

(Tensile test) In accordance with JIS-K-7113, a No. 2 test piece described in JIS-K-7113 was used.

(Measurement of Resin Density) JIS-K-7112
The measurement was carried out by an underwater substitution method in conformity with.

(Water resistance) The dissolution rate of the flame retardant when a 0.5 × 1.5 × 0.125 inch (about 1.7 g) test piece was immersed in 100 ml of hot water at 70 ° C. for 2 days It was evaluated by measuring.

Example 1 To 100 parts by weight of polypropylene (7030B manufactured by Tosoh Corporation), 1 melamine phosphate (MPP-A manufactured by Sanwa Chemical Co., Ltd.) was used.
Two parts and 12 parts of ethylenediamine phosphate (Amgard NK manufactured by Albright & Wilson Americas) were mixed, and roll kneading was performed at 180 ° C. Next, the resin composition obtained by roll kneading is heated to 190 ° C. and 120 kg.
/ Cm 2 was press-molded for 4 minutes, various test pieces for evaluation were prepared from this molding resin, and measurement and evaluation were performed. Table 1 shows the results.

[0026]

[Table 1]

Examples 2 to 5 Melamine phosphate, 100 parts by weight of polypropylene,
Various test pieces for evaluation were prepared in the same manner as in Example 1 except that ethylenediamine phosphate was mixed in the weight parts shown in Table 1, and the measurement and evaluation were performed. The results are shown in Table 1.

Comparative Example 1 100 parts by weight of polypropylene (7030B manufactured by Tosoh Corporation) was mixed with 100 parts by weight of melamine phosphate, and Example 1 was used.
Various test pieces for evaluation were prepared by the same method as described above, and measurement and evaluation were performed. The results are shown in Table 1.

Comparative Example 2 100 parts by weight of polypropylene (7030B manufactured by Tosoh Corporation) was mixed with 100 parts by weight of ethylenediamine phosphate, and various kinds of test pieces for evaluation were prepared in the same manner as in Example 1 and evaluated. It was The results are shown in Table 1.

Comparative Example 3 Various comparative test pieces were prepared in the same manner as in Comparative Example 1 except that magnesium hydroxide (Kisuma 5B manufactured by Kyowa Kagaku Co., Ltd.) was used instead of melamine phosphate. . The results are shown in Table 1.

Comparative Example 4 In Example 1, ammonium polyphosphate (Exolit 46 manufactured by Hoechst) was used instead of melamine phosphate.
Various evaluation test pieces were prepared by the same method except that 2) was used, and measurement and evaluation were performed. The results are shown in Table 1.

As is clear from the above examples and comparative examples, the combined use of melamine phosphate and ethylenediamine phosphate synergistically enhances the flame retardant effect, and shows excellent flame retardancy even at low compounding amounts. It was

Claims (3)

[Claims] 1. A flame-retardant polyolefin resin composition comprising 100 parts by weight of polyolefin and 3 to 30 parts by weight of melamine phosphate and 3 to 30 parts by weight of ethylenediamine phosphate as a flame retardant. 2. The total amount of melamine phosphate and ethylenediamine phosphate is 6 with respect to 100 parts by weight of polyolefin.
The flame-retardant polyolefin composition according to claim 1, wherein the flame-retardant polyolefin composition is about 40 parts by weight. 3. The flame-retardant polyolefin according to claim 1, wherein melamine phosphate and ethylenediamine phosphate are mixed in a ratio of 80:20 to 20:80 (weight ratio). Composition.