JP3306759B2 - Flame retardant polypropylene resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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 which generates little corrosive gas and harmful gas and has high flame retardancy.

[0002]

2. Description of the Related Art Due to its excellent properties, polypropylene resin is used in the form of injection molded products, films and blow molded products.
It is widely used in fields such as automobiles, building materials, and electrical components.

[0003] However, polypropylene resins have the drawback of being extremely flammable, and as their applications have spread, there have been many demands for flame retardancy and the level of flame retardancy has also increased.

In general, the flame retardation of an organic polymer is achieved by (1) adding a flame retardant to a resin, (2) blending a flame retardant resin, and (3) producing a flame retardant polymer by reaction with a flame retardant monomer. It is done in the method of. Of these, the most commonly used method is to add a flame retardant to the resin, and the polypropylene resin is usually used in this method. Addition-type flame retardants include halides such as organic chlorinated compounds and bromide compounds, phosphorus-containing compounds such as phosphate esters, phosphite esters, phosphorus and ammonium phosphate, and water-containing inorganic compounds such as aluminum hydroxide and magnesium hydroxide. Antimony trioxide is usually used as a flame retardant aid.

[0005] Of these, the most commonly used method for making a polypropylene resin flame-retardant is the combined use of a halogen-based flame retardant and antimony trioxide. However, a resin composition containing a halogen-based flame retardant generates corrosive gas during processing and combustion, causing equipment trouble,
It also has the disadvantage of generating harmful gases such as hydrogen halide. As such a flame-retardant polypropylene resin composition to which no halogen-based flame retardant is added, a method of adding magnesium hydroxide or ammonium polyphosphate has been proposed. However, the composition to which magnesium hydroxide is added requires a large amount of magnesium hydroxide to obtain sufficient flame retardancy.
This leads to a reduction in workability. Further, in the composition using ammonium polyphosphate, a nitrogen compound used as a co-reactant,
Poor dispersibility of pentaerythritol, occurrence of bleed, and decrease in water resistance are observed.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to have high flame retardancy, generate very little corrosive gas and harmful gas, and have excellent workability, physical properties, water resistance and bleed resistance. To provide a flame-retardant polypropylene-based resin composition.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, it has been found that ammonium polyphosphate or modified ammonium polyphosphate, melamine compounds, pentaerythritols and polyamides are added to polypropylene resin. Or by adding an amide compound, it has a high degree of flame retardancy, and extremely low generation of corrosive gas and harmful gas, 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) a polypropylene resin, (B) an ammonium polyphosphate or a melamine-modified ammonium polyphosphate, (C) a melamine compound,
(D) a pentaerythritol and (E) a polypropylene-based resin composition comprising a polyamide or an amide compound, the resin composition comprising (B) an ammonium polyphosphate or a melamine-modified ammonium polyphosphate, (C) a melamine compound, D) The composition ratio of the pentaerythritols on the triangular coordinates is point a (80, 10, 10), point b (60, 30, 10), point c (60, 10, 30) (in parentheses, the composition B, C) and (D), and the total amount of the three components is 25 to 45% by weight of the total composition. It is a polypropylene-based resin composition containing 20% by weight of a polyamide and an amide compound.

[0009] 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 bleed resistance.

The polypropylene resin used in the present invention includes 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.

As the 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 alone, melamine cyanurate, melamine homopolymer, melamine formaldehyde polymer and the like.

As the pentaerythritol used in the present invention, pentaerythritol and dipentaerythritol which are usually commercially available can be used.

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

The total amount of these three components is 20 to
It is 45% by weight, more preferably 25 to 40% by weight.
If the amount is less than 20% by weight, sufficient flame retardancy cannot be obtained. If the amount is more than 45% by weight, physical properties, water resistance and bleed resistance tend to deteriorate.

The polyamides and amide compounds used in the present invention are generally commercially available polyamide resins (nylon 6, nylon 66, nylon 12, nylon 11),
Additives for resins (such as stearic acid amide) can be used. The 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, poor flame retardancy and poor dispersion may result. On the other hand, if the blending amount is more than 10% by weight, the flame retardant effect hardly changes.

In the resin composition of the present invention, a compound usually used as a flame retardant auxiliary agent, for example, an inorganic tin salt and zinc borate can be used in a usual range. By blending these, improvement in flame retardancy and suppression of glowing can be achieved.

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

In the resin composition of the present invention, rubber and the like can be used in the range where they are usually used, and physical properties such as impact strength can be improved.

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

In the present invention, in addition to the above, additives usually used as polyolefin resin additives, for example, antioxidants, light stabilizers, ultraviolet absorbers and stabilizers can be added.

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

[0023]

EXAMPLES The present invention will be described in detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto. still,
Various test methods performed in the examples and comparative examples are as follows.

Flame Retardancy Test Oxygen Index: According to JIS K7201 “Method for Combustion Test of Polymer Materials by Oxygen Index Method”.

UL94: According to the UL94 vertical combustion test.

The test pieces were prepared using an injection molding machine.

Evaluation of Bleed Resistance A flat plate of 100 × 65 × 3 mm was prepared using an injection molding machine. This was placed in a thermo-hygrostat at 70 ° C. and 90% humidity for 1 hour.
After processing for 68 hours, it was taken out and visually inspected for the bleed state.

Example 1 Polypropylene resin (manufactured by Tosoh Corporation: J5100)
A, MFR 10, homopolymer) 65% by weight of ammonium polyphosphate (Exolit 4 manufactured by Hoechst KK)
62) 22% by weight, melamine (manufactured by 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 The antioxidant was added in the composition 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 mmφ to produce pellets. Next, test pieces were prepared from the pellets at a resin temperature of 230 ° C. using a 150-t injection molding machine and evaluated. The results are shown in Table 1. The obtained resin composition 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 obtained resin composition 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 in the same manner as described above and evaluated. The results are shown in Table 1. The obtained resin composition was good in both flame retardancy and bleed resistance.

Example 4 Test pieces were 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 obtained resin composition 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.
Test pieces were prepared and evaluated in the same manner as described above. The results are shown in Table 1. The obtained resin composition was good in both flame retardancy and bleed resistance.

Comparative Example 1 Ammonium polyphosphate 24% by weight, melamine 8% by weight,
A test piece was 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 obtained resin composition 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 weight parts of pentaerythritol were used. Table 1 shows the results.
The resulting resin composition is inferior in both flame retardancy and bleed 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 18% by weight of ammonium polyphosphate, 12% by weight of melamine and 4% by weight of pentaerythritol were used. The results are shown in Table 1. The obtained resin composition had bleed resistance,
Poor flame retardancy.

COMPARATIVE EXAMPLE 5 18% by weight of ammonium polyphosphate, 8% by weight of melamine,
Test pieces were prepared and evaluated in the same manner as in Example 1 except that pentaerythritol was 8% by weight. 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 clear from the above description, the composition of the present invention has a high degree of flame retardancy and excellent bleeding resistance, generates very little corrosive gas and harmful gas, and has good processability. It is a composition with excellent physical properties.

Claims (2)

(57) [Claims] (A) a polypropylene resin, (B) ammonium polyphosphate or melamine-modified ammonium polyphosphate, (C) a melamine compound, (D) pentaerythritols, and (E) a polyamide resin or a fatty acid polyamide.
(B) ammonium polyphosphate or melamine
Modified ammonium polyphosphate, (C) melamine compound,
(D) The composition ratio of pentaerythritols on triangular coordinates
Point a (80, 10, 10), point b (60, 30,
10), point c (60, 10, 30) (in parentheses, composition
B, C, and D in that order), and
Polyamide having a total of 20 to 45% by weight of the three components
The total amount of the resin and the fatty acid amide is 0.01 to 20 weight
% Flame-retardant polypropylene-based resin composition. 2. The polyamide resin is nylon 12, Nylon.
2. The flame-retardant polypropylene-based material according to claim 1,
Resin composition.