JPH06184374A - Flame-retardant polypropylene resin composition - Google Patents

Abstract

PURPOSE:To provide the subject composition which has high flame retardancy and excellent bleeding resistance, very scarcely forms corrosive gases and noxious gases and is excellent in processability and physical properties. CONSTITUTION:This resin composition is prepared by mixing a polypropylene resin with a polyammonium phosphate or a melamine-modified polyammonium phosphate, a melamine compound, a pentaerythritol and a polyamide or an amide compound.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a flame-retardant polypropylene resin composition. More specifically, the present invention relates to a flame-retardant polypropylene-based resin composition having a high degree of flame-retardant property with less generation of corrosive gas and harmful gas.

[0002]

2. Description of the Prior Art Polypropylene resins are excellent in their properties and can be used in the form of injection molded products, films and blow molded products.
Widely used in the fields of automobiles, building materials, electric parts, etc.

However, polypropylene resins have the drawback that they are extremely flammable, and as their applications are widespread, there are many demands for flame retardancy, and the flame retardancy level is increasing.

Generally, in order to make an organic polymer flame-retardant, (1) a flame-retardant agent is added to a resin (2) a flame-retardant resin is blended (3) a flame-retardant polymer is produced by a reaction with a flame-retardant monomer, etc. It is done by the method of. The most commonly used method among these is the method of adding a flame retardant to the resin, which is usually used for polypropylene resins. Addition-type flame retardants include organic chlorides, bromides and other halides, phosphates, phosphites, phosphorus, phosphorus-containing compounds such as ammonium phosphate, aluminum hydroxide, magnesium hydroxide and other hydrous inorganic compounds. Also, antimony trioxide is commonly used as a flame retardant aid.

Of these, the method of adding a halogen-based flame retardant and antimony trioxide together is most commonly used for flame retarding polypropylene resins. However, a resin composition containing a halogen-based flame retardant generates a corrosive gas during processing and combustion, causing equipment trouble,
Further, it has a drawback that it emits harmful gas such as hydrogen halide. As a flame-retardant polypropylene resin composition to which such a halogen-based flame retardant is not added, a method of adding magnesium hydroxide or ammonium polyphosphate has been proposed. However, a composition to which magnesium hydroxide is added requires addition of a large amount of magnesium hydroxide in order to obtain sufficient flame retardancy, and as a result, physical properties,
It causes a decrease in workability. Further, in a composition using ammonium polyphosphate, a nitrogen compound used as a co-reactant,
Poor dispersibility of pentaerythritol, occurrence of bleeding, and deterioration of water resistance are observed.

[0006]

The object of the present invention is to have a high degree of flame retardancy, generate very little corrosive gas and harmful gas, and be excellent in workability, physical properties, water resistance and bleeding resistance. Another object of the present invention is to provide a flame-retardant polypropylene resin composition.

[0007]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that ammonium-based polyphosphates or modified ammonium polyphosphates, melamine compounds, pentaerythritols and polyamides are added to polypropylene resins. Or by adding an amide compound, it has a high degree of flame retardancy, and extremely little corrosive gas, harmful gas generation, processability, physical properties, water resistance,
It has been found that a flame-retardant polypropylene resin composition having excellent bleed resistance can be obtained.

That is, the present invention provides (A) polypropylene resin, (B) ammonium polyphosphate or melamine-modified ammonium polyphosphate, (C) melamine compound,
(D) Pentaerythritols and (E) Polypropylene-based resin composition comprising polyamide or amide compound, wherein the resin composition is (B) ammonium polyphosphate or melamine-modified ammonium polyphosphate, (C) melamine compound, ( D) The composition ratio of pentaerythritols on the triangular coordinate is a point (80, 10, 10), b point (60, 30, 10), c point (60, 10, 30) (in parentheses, composition B, C and D), and a polypropylene resin composition having a total content of three components of 25 to 45% by weight based on the total composition and a composition of these compositions of 0.05 It is a polypropylene resin composition containing about 20% by weight of polyamide and an amide compound.

The resin composition of the present invention is a flame-retardant polypropylene resin composition which is extremely excellent in processability, physical properties, water resistance and bleeding resistance.

The polypropylene resin used in the present invention is a polypropylene homopolymer, a block copolymer or a random copolymer of propylene and ethylene, butene-1, pentene-1, hexene-1, 4-methylpentene-1. , As well as mixtures thereof can be used.

As the ammonium polyphosphate melamine-modified ammonium polyphosphate used in the present invention, those commercially available for flame retardants can be used. These ammonium polyphosphates may be microencapsulated by a usual method using a thermosetting resin.

The melamine compound used in the present invention may be a commercially available one such as melamine simple substance, melamine cyanurate, melamine homopolymer and melamine formaldehyde polymer.

As the pentaerythritols used in the present invention, those commercially available as pentaerythritol and dipentaerythritol can be used.

The composition of (B) ammonium polyphosphate (C) melamine or melamine compound (D) and pentaerythritol to be blended in the present invention has a composition ratio of three components at point a (80, 10, 10), point b (6
0, 30, 10), a range surrounded by points c (60, 10, 30), more preferably point d (75, 15, 10), b
It is preferably within the range surrounded by the points (60, 30, 10) and the point e (60, 15, 25). If it exceeds the range, sagging may occur, foaming may be insufficient, or carbide may not be sufficiently generated, so that sufficient flame retardancy may not be obtained.

The total blending amount of these three components is 20 to
It is 45% by weight, more preferably 25-40% by weight.
When the content is less than 20% by weight, sufficient flame retardancy cannot be obtained, and when it is more than 45% by weight, physical properties, water resistance and bleeding resistance tend to be deteriorated.

Polyamides and amide compounds used in the present invention are generally commercially available polyamide resins (nylon 6, nylon 66, nylon 12, nylon 11),
Resin additives (such as stearic acid amide) can be used. The blending amount is preferably 0.01 to 20% by weight, more preferably 0.05 to 10% by weight. If the blending amount is less than 0.05% by weight, flame retardancy and dispersion may be poor. On the other hand, if the blending amount is more than 10% by weight, the flame retardant effect hardly changes.

Further, the resin composition of the present invention may be used in combination with those which are usually used as a flame retardant aid, for example, an inorganic tin salt and zinc borate within a usual range of use. By blending these, flame retardancy is improved and glowing is suppressed.

It is also possible to improve the physical properties by adding an inorganic filler to the resin composition of the present invention within the range usually used. For these purposes, talc, mica, silica, calcium silicate, glass fiber, carbon fiber, calcium carbonate and the like are usually used.

Further, it is possible to improve physical properties such as impact strength by using rubber or the like in the resin composition of the present invention in a range usually used.

Further, in the resin composition of the present invention, a modified polypropylene resin used for the purpose of improving the compatibility with additives and improving the physical properties can be used within the range usually used.

Further, in the present invention, in addition to the above substances, those which are usually used as additives for polyolefin resins, for example, antioxidants, light stabilizers, ultraviolet absorbers and stabilizers can be added.

The flame-retardant polyolefin resin composition thus obtained can be molded into a molded product by a usual processing method such as injection molding, extrusion molding, blow molding and the like.

[0023]

The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. still,
Various test methods carried out in Examples and Comparative Examples are as follows.

Flame retardant test Oxygen index: According to JIS K7201 "Combustion test method for polymer materials by oxygen index method".

UL94: According to the UL94 vertical burning test.

The test pieces were prepared using an injection molding machine.

Evaluation of bleeding resistance A flat plate of 100 × 65 × 3 mm was prepared using an injection molding machine. 1 in a thermo-hygrostat at a temperature of 70 ° C and a humidity of 90%
After the treatment for 68 hours, it was taken out and the bleeding state was visually evaluated.

Example 1 Polypropylene resin (manufactured by Tosoh Corporation: J5100)
A, MFR 10, homopolymer) 65% by weight ammonium polyphosphate (manufactured by Hoechst KK, Exorit 4)
62) 22% by weight, melamine (Nissan Chemical Co., Ltd .: general product) 8% by weight, pentaerythritol (Koei Chemical Industry Co., Ltd .: general product) 4% by weight and stearic acid amide 1.0% by weight, and An antioxidant was added according to the formulation shown in Table 1, mixed with a Henschel mixer, and extruded at 220 ° C. with a twin-screw kneading extruder having a diameter of 30 mm to produce pellets. Then, a test piece was prepared from the pellet with a 150-ton injection molding machine at a resin temperature of 230 ° C. and evaluated. The results are shown in Table 1. The resin composition obtained was good in both flame retardancy and bleed resistance.

Example 2 A test piece was prepared and evaluated in the same manner as in Example 1 except that a block polymer (J7250B, MFR 25 manufactured by Tosoh Corporation) was used as the polypropylene resin. The results are shown in Table 1. The resin composition obtained was good in both flame retardancy and bleed resistance.

Example 3 Example 1 was repeated except that nylon 12 (3024 LU manufactured by Ube Industries, Ltd.) was used instead of stearic acid amide.
A test piece was prepared and evaluated in the same manner as in. The results are shown in Table 1. The resin composition obtained was good in both flame retardancy and bleed resistance.

Example 4 A test piece was prepared and evaluated in the same manner as in Example 1 except that melamine cyanurate was used instead of melamine. The results are shown in Table 1. The resin composition obtained was good in both flame retardancy and bleed resistance.

Example 5 Ammonium polyphosphate 24% by weight, melamine 6% by weight,
Example 1 except that pentaerythritol was 4% by weight.
A test piece was prepared and evaluated in the same manner as in. The results are shown in Table 1. The resin composition obtained was good in both flame retardancy and bleed resistance.

Comparative Example 1 Ammonium polyphosphate 24% by weight, melamine 8% by weight,
Test pieces were prepared and evaluated in the same manner as in Example 1 except that pentaerythritol was 2% by weight. The results are shown in Table 1. The resin composition obtained has good bleeding resistance but poor flame retardancy.

Comparative Example 2 Ammonium polyphosphate 22% by weight, melamine 4% by weight,
Test pieces were prepared and evaluated in the same manner as in Example 1 except that 8 parts by weight of pentaerythritol was used. The results are shown in Table 1.
However, the obtained resin composition is inferior in both flame retardancy and bleeding resistance.

Comparative Example 3 A test piece was prepared and evaluated in the same manner as in Example 1 except that the amide compound was not added. The results are shown in Table 1, and the obtained resin composition is inferior in flame retardancy and bleed resistance.

Comparative Example 4 A test piece was prepared and evaluated in the same manner as in Example 1 except that ammonium polyphosphate was 18% by weight, melamine was 12% by weight, and pentaerythritol was 4% by weight. The results are shown in Table 1. The resin composition obtained had bleed resistance,
Inferior in flame retardancy.

Comparative Example 5 Ammonium polyphosphate 18% by weight, melamine 8% by weight,
Test pieces were prepared and evaluated in the same manner as in Example 1 except that 8% by weight of pentaerythritol was used. The results are shown in Table 1, and the obtained resin composition is inferior in bleed resistance and flame retardancy.

[0038]

[Table 1]

[0039]

As is apparent from the above description, the composition of the present invention has a high degree of flame retardancy and excellent bleeding resistance, and has extremely little generation of corrosive gas and harmful gas, and has excellent processability. It is a composition having excellent physical properties.

Claims (3)

[Claims] 1. A flame-retardant material comprising (A) polypropylene resin, (B) ammonium polyphosphate or melamine-modified ammonium polyphosphate, (C) melamine compound, (D) pentaerythritol and (E) polyamide or amide compound. Polypropylene resin composition. 2. (B) Ammonium polyphosphate or melamine-modified ammonium polyphosphate, (C) Melamine compound,
(D) The composition ratio of pentaerythritols is a point (80, 10, 10), b point (60, 30,
10) and point c (60, 10, 30) (inside the parentheses are listed in order of composition B, C, D), and within the region surrounded by three components, and the total of the three components is 20 to 45% by weight. Item 2. The polypropylene resin composition according to Item 1. 3. The total amount of polyamide and amide compound is from 0.01 to 20% by weight.
The flame-retardant polypropylene-based resin composition described in 1.