JPS61168643A - Flame-retardant polyolefin composition - Google Patents

Abstract

PURPOSE:To improve greatly thermal stability and to prevent moldings from causing blooming, by blending an org. halogen-contg. flame retarder and an aliph. carboxylic acid with a polyolefin. CONSTITUTION:A 100pts.wt. polyolefin (a), 0.5-30pts.wt. org. halogen-contg. flame retarder (b) and 0.01-5pts.wt. aliph. carboxylic acid (c) having a m.p. of 60 deg.C or below are blended together. Pref. 10-100wt% (based on the quantity of the halogen-contg. flame retarder) antimony trioxide is added thereto. Examples of component (c) are satd. fatty acids such as caproic or lauric acid and unsaturated fatty acids such as oleic or elaidic acid, among which the satd. fatty acids are preferred. Preferred examples of component (b) are etherified tetrabromobisphenol A, etherified tetrabromobisphenol S, brominated alkyl isocyanurate and chlorinated paraffin.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to flame-retardant polyolefin compositions having a high degree of thermal stability and blooming resistance.

[Prior Art and Problems] Since polyolefin is composed of hydrocarbons, ignition is difficult. Polyolefins have the disadvantage of being easily flammable, and for this reason various proposals have been made regarding the flame retardancy of polyolefins.

In recent years, polyolefins used in electrical products, building materials, etc. are increasingly required to have a higher degree of flame retardancy. For example, in the U.S. JL standard, parts of electrical products such as TV frames and audio parts are given V- to v-0, respectively.
, or a flame retardancy of V-2 or the like is required. Furthermore, in our country as well, various types of flame retardancy are naturally required.

In this background, various attempts have been made to use inorganic flame retardants and organic flame retardants as flame retardants for polyolefins. In general, inorganic flame retardants have good fire-retardant properties, but in order to impart a sufficient flame retardant effect, they require a large amount of filling. On the other hand, organic flame retardants have a greater flame retardant effect than inorganic flame retardants, so they only need to be added in small amounts.
On the other hand, due to its high reactivity, it partially decomposes during melt-kneading.
There were problems in that so-called "staining" occurred, yellowing was likely to occur, and thermal stability was lacking.

From this point of view, the inventors of Hyo have already proposed a heat-stabilized flame-retardant polyolefin composition containing etherified bisphenol tetrabromide, antimony trioxide, and a metal salt of a higher fatty acid (Japanese Patent Publication No. 51-1999). 25081). That is, the above proposal has greatly improved the thermal stability of flame-retardant polyolefin compositions. However, such flame-retardant polyolefin compositions may still not have sufficient thermal stability depending on the type of extruder or injection molding machine and the shape of their screws.

[Means for Solving the Problem] As a result of further intensive research into the above-mentioned flame-retardant polyolefin composition, the present inventors found that the blending of aliphatic carbon having a melting point of 60° C. or less resulted in a flame-retardant polyolefin composition. The present invention was developed based on the finding that the method is very effective in improving the thermal stability of olefin compositions and is also effective in preventing blooming (whitening) in molded products. That is, the present invention provides a flame retardant containing 0.5 to 30 parts by weight of an organic halogen flame retardant and 0.01 to 5 parts by weight of an aliphatic carboxylic acid having a melting point of 60° C. or less per 100 parts by weight of polyolefin. It is a flammable polyolefin composition.

In the present invention, it is possible to obtain a flame-retardant polyolefin composition that has good thermal stability during melt mixing and is less likely to be colored or so-called "scorched" due to decomposition.

Furthermore, this composition prevents the blooming phenomenon that occurs when various additives, including flame retardants, are deposited on the surface of the molded product and deteriorates the appearance of the molded product.

The polyolefin used in the present invention includes ethylene,
Homopolymers of α-olefins such as propylene and butylene, random copolymers and block copolymers of the α-olefins and other α-olefins, block copolymers, and mixtures thereof can be mentioned, and in particular those mainly composed of polypropylene. Polyolefins are preferably used.

In addition, organic halogen flame retardants include hexabromobenzene, pentabromobenzene, pentabromotoluene,
Brominated aromatic compounds such as tetrabromotoluene, tetrabromoxylene, tribromoxylene, pentabromophenol, tetrabromoresorcin, tribromopyrogallol, brominated biphenyls, brominated diphenyl ethers, brominated diphenylthioethers, brominated naphthalene derivatives; hexa Chlorobenzene, pentachlorobenzene,
Chlorinated aromatic compounds such as pentachlorotoluene, tetrachlorotoluene, tetrachloroxylene, trichloroxylene, pentachlorphenol, tetrachlorresorcin, trichlorpyrogallol, chlorinated biphenyls, chlorinated diphenyl ethers, chlorinated diphenylthioethers, chlorinated naphthalene derivatives, etc. Brominated aliphatic compounds such as tetrabromobutane, pentachlorpentane, hexabromohexane, heptabromohebutane, brominated paraffin; Chlorine such as tetrachlorobutane, pentachlorpentane, hexachlorohexane, heptachlorhebutane, chlorinated paraffin, etc. Brominated aliphatic compounds; brominated bisphenol A, chlorinated bisphenol A, brominated bisphenol A
(brominated aliphatic ether), chlorinated bisphenol A (
halogenated bisphenol A derivatives such as chlorinated aliphatic ether); brominated bisphenol S, chlorinated bisphenol S, brominated bisphenol (brominated aliphatic ether), chlorinated bisphenol S (chlorinated aliphatic ether)
halogenated bisphenol derivatives such as tris(dibromopropyl) cyanurate, bis(dibromopropyl)
Brominated alkyl cyanurates such as cyanurate, tris(tetrabromopentyl) cyanurate; brominated alkyl isocyanurates such as tris(dibromopropyl)isocyanurate, bis(dibromopropyl)isocyanurate, tris(tetrabromopentyl)isocyanurate : Chlorinated alkyl cyanurates such as tris(dichlorpropyl) cyanurate, bisdiculbrovir) cyanurate, tris(tetrachlorpentyl) cyanurate; tris(dichloropropyl) isocyanurate,
Bis(dichloropropyl)isocyanurate, tris(
chlorinated alkyl isocyanurates such as (tetrachlorpentyl) isocyanurate; and the like, in particular 51CH315r (wherein R and R are an alkyl group having 2 to 10 carbon atoms bonding at least two bromine atoms of the same or different types). )
Etherified tetrabrominated bisphenol A1 having the following formula (wherein R3 and - are an alkyl group having 2 to 10 carbon atoms bonding at least two bromine atoms of the same or different type) S1 I (However, R3, R6 and R7 are alkyl groups having 2 to 10 carbon atoms bonding at least two bromine atoms of the same or different types.) Brominated alkyl isocyanurate,
Chlorinated paraffin and the like are preferably used.

The blending amount of organic halogen flame retardant is polyolefin 10
0.5 to 30 to 0 parts by weight! Quantity part, preferably 1~
It is 20 parts by weight. When the amount of the organic halogen flame retardant is less than the above lower limit, a sufficient flame retardant effect cannot be exhibited, and when it is more than the above upper limit, thermal stability deteriorates, which is not preferable.

In addition, fatty acids with melting points of 60°C or lower include caproic acid,
Examples include saturated fatty acids such as caprylic acid, capric acid, lauric acid, and myristic acid; unsaturated fatty acids such as oleic acid, erucic acid, and elaidic acid; saturated fatty acids are particularly preferably used. The blending amount of the fatty acid with a melting point of 60°C or lower is 0.01 parts by weight per 100 parts by weight of the polyolefin.
~5 parts by weight, preferably 0.03 to 3 parts by weight. If the blending amount of the fatty acid with a melting point of 60°C or less is less than the lower limit, sufficient heat stabilizing effect cannot be achieved, and if it is greater than the upper limit, it may be difficult to produce polyolefin molded products. The problem is that it is too slippery, making it impossible to produce stable molded products.

In the present invention, a highly flame-retardant polyolefin composition is achieved by further blending antimony trioxide with a polyolefin, an organic halogen flame retardant, and an aliphatic carboxylic acid having a melting point of 60° C. or less. The content of antimony trioxide is generally 10 to 100% by weight based on the organic halogen flame retardant.

In the present invention, the order of mixing polyolefin, organic halogen flame retardant, aliphatic carboxylic acid having a melting point of 60°C or lower, and antimony trioxide is not particularly limited, and each component may be mixed at the same time, or several types may be mixed. The ingredients may be mixed in advance and the rest may be mixed later.

The mixing method is also not particularly limited, and is generally carried out using a tumbler blender, a type blender, a Henschel mixer, a ribbon mixer, or the like.

Furthermore, it is also possible to use a method in which several types are mixed in advance in a Henschel mixer, and then the remaining ingredients are added and mixed in a tumbler, changing the mixing order and equipment.

The polyolefin composition of the present invention is based on components consisting of a polyolefin, an organic halogen system, a flame retardant, an aliphatic carboxylic acid with a melting point of 60°C or less, and further antimony trioxide, but other than these components If necessary, conventionally known stabilizers, colorants, antistatic agents, lubricants, nucleating agents, etc. may be added.

[Actions and Effects] The flame-retardant polyolefin composition of the present invention has high thermal stability and blooming resistance.

The reason why such a high degree of thermal stability is obtained is not clear, but in the polyolefin composition of the present invention, the carboxylic acid first melts in the extruder, creating a state in which the specified flame retardant and polyolefin are easily mixed uniformly. For,
It is presumed that this prevents the flame retardant from being present in high concentrations locally.

Furthermore, flame-retardant polyolefin compositions generally often contain various substances such as the above-mentioned additives in addition to flame retardants. Among these, they may precipitate on the surface of the molded product, causing a blooming phenomenon (whitening phenomenon). In the flame-retardant polyolefin composition of the present invention, since the blended aliphatic carboxylic acid has a low melting point of 60°C or less, it migrates to the surface of the molded product of the polyolefin composition, exhibiting the phenomenon of lowering the melting point, and causing blooming. It is assumed that this will have the effect of preventing this phenomenon.

[Examples] In order to explain the present invention more specifically, Examples and Comparative Examples will be described below, but the present invention is not limited to these Examples.

In addition, the results of the combustion tests shown in Examples and Comparative Examples are Ul,
It complies with Section 94 of the standard (test piece thickness 178
inches), and the yellowness measurement results are from Suga! ! ll5M
Using a color computer SM-3-CH, it was indicated by yellow index (Y[). The higher the yellowness, the higher the value.

Example 1 100 parts by weight of polypropylene (PN640 manufactured by Tokuyama Soda Co., Ltd.), dibromopropyl etherified tetrabromobisphenol S, (nonnene PR-2 manufactured by Marubishi Yuka) aliphatic carboxylic acid in the proportions shown in Table 1 , aliphatic carboxylic acid metal salt, antimony trioxide, and heat stabilizer were mixed in a super mixer. In addition, the heat stabilizer is 2,6-diter
t-Butyl-4-methylphenol and dilaurylthiopropionate were added to the total composition at 0.1% and 0.2%, respectively.Then, they were melted using a 40 m/m extruder. The mixture was kneaded and pelletized. This pellet was molded using a 207 injection molding machine to obtain a combustion test piece and a color plate for color measurement.

Using this combustion test piece, a combustion test (Ul, standard 5b94
), and the results are also listed in Table 1.

Further, the color plate for color measurement was measured with a colorimeter manufactured by Suga Co., Ltd. to obtain yellowness (Y, 1.). These results are also listed in Table 1.

Furthermore, this color plate should be kept free from dust (40℃).
After buying the product for three months, the surface was observed and the presence or absence of the blooming phenomenon was determined. These results are also listed in Table 1.

Example 2 The flame retardant, fatty acid, fatty acid metal salt, and antimony trioxide shown in Table 2 were added to 100 parts by weight of polypropylene (PN240 manufactured by Tokuyama Soda Co., Ltd.) in the proportions shown in Table 2. An experiment was conducted in the same manner as in Example 1, and measurement results of flame retardancy and yellowness were obtained. These values are also listed in Table 2.

Margin below

Claims (7)

[Claims] (1) 0.5 to 30 parts by weight of an organic halogen flame retardant and a melting point of 60°C per 100 parts by weight of polyolefin
A flame-retardant polyolefin composition containing 0.01 to 5 parts by weight of the following aliphatic carboxylic acid. (2) The composition according to claim 1, wherein the organic halogen flame retardant is etherified tetrabrominated bisphenol A having the following general formula. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R_1 and R_2 are alkyl groups with 2 to 10 carbon atoms that bond at least two bromine atoms of the same or different types.) (3) The composition according to claim 1, wherein the organic halogen flame retardant is etherified tetrabrominated bisphenol S having the following general formula. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R_3 and R_4 are alkyl groups with 2 to 10 carbon atoms that bond at least two bromine atoms of the same or different types.) (4) The composition according to claim 1, wherein the organic halogen flame retardant is an ester of isocyanuric acid and brominated aliphatic alcohol having the following general formula. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (However, R_5, R_6, and R_7 are alkyl groups with 2 to 10 carbon atoms that bond at least two bromine atoms of the same or different types.) (5) The composition according to claim 1, wherein the organic halogen flame retardant is a chlorinated paraffin. (6) The composition according to claim 1, wherein the polyolefin is polypropylene. (7) 0.5 to 30 parts by weight of an organic halogen flame retardant, 0.01 to 5 parts by weight of an aliphatic carboxylic acid with a melting point of 60°C or less, and antimony trioxide to 100 parts by weight of the polyolefin. 10-10 for halogenated flame retardants
A flame-retardant polyolefin composition containing 0% by weight.