JPH0680132B2 - Stabilized flame-retardant styrene resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a heat-stabilized flame-retardant styrene resin composition.

Since styrene resins have excellent physical properties, they are used in various applications such as electric appliances, upholstery and building materials. However, styrene resins are flammable. Flame retardancy is regulated for some applications.

[Conventional technology]

To make the styrene resin flame-retardant, flame retardants such as polychlorinated organic compounds, polybrominated organic compounds, antimony trioxide, and phosphorus compounds are added. Of these, halogen-based flame retardants are particularly effective and are often used. However, halogen-based flame retardants are unstable at high temperatures and are easily decomposed, so styrene-based resins containing them are colored during processing.

Therefore, in order to prevent coloring by these flame retardants, organic tin compounds (Japanese Patent Publication No. 47-22090), organic tin compounds and antioxidants (Japanese Patent Publication No. 46-16481, Japanese Patent Publication No. 47-9744),
Hydrotalcite (JP-A-60-86143) and the like are added.

[Problems to be solved by the invention]

However, since the above styrenic resin has a particularly high processing temperature (200 ° C or higher), the addition of an organic tin compound (and an antioxidant) has an insufficient effect of suppressing coloration during processing, and the addition of hydrotalcite When added, plate-out is significant, and thermal stability and initial colorability are unsatisfactory. There is a demand for the development of excellent stabilizers that prevent these thermal deterioration and plate-out.

[Means for solving problems]

As a result of various studies, the present inventors have found that styrene resin containing halogen flame retardant can be thermally stabilized even at high temperature processing by adding perhydrochloric acid ion exchange and adding hydrotalcites incorporating polyhydric alcohol. The present invention has been completed by finding out that it is possible to improve the plate-out.

That is, the present invention, when heat-stabilizing a flame-retardant resin consisting of 100 parts by weight of styrene resin and 1 to 50 parts by weight of halogen-based flame retardant, Mg-Al-2 valent anion type hydrotalcites, By contacting with perchloric acid in the presence of water and a polyhydric alcohol or its partial ester, 20 to 80% of the divalent anions of hydrotalcites are exchanged with perchlorate ions, and at the same time, polyhydric alcohol or A stabilized flame-retardant styrene-based resin composition, which comprises adding 0.01 to 5 parts by weight of a composite hydroxide having the partial ester incorporated in a crystal layer structure or a dried or calcined product thereof.

Further, the present invention provides a method for thermally stabilizing the above flame retardant resin,
(A) 0.01 to 5 parts by weight of the above-mentioned hydrotalcites containing polyhydric alcohol exchanged with perchlorate ion, and (b) dialkyltin maleate, dialkyltin maleate, dialkyltin thiodiene. A stabilized flame-retardant styrenic resin composition, characterized in that one or more propionates or dialkyltin dithiodipropionates are added together with 0.01 to 5 parts by weight.

In the present invention, perchlorate ion exchange-polyhydric alcohol-incorporated hydrotalcites added to heat-stabilize the flame-retardant resin have the general formula MgxAly (OH) _{2x + 3y-2z} (A ^2- ) _z・ KH ₂ O (In the formula, A ²⁻ is a divalent anion such as CO ₃ ²⁻ and SO ₄ ²⁻ , x, y and z are Is a positive number that satisfies The hydrotalcites represented by the formula (4) and perchloric acid are brought into contact with each other in the presence of water and a polyhydric alcohol or a partial ester thereof to obtain 20 to 80 divalent anions of hydrotalcite. % together with exchanged perchlorate ion, a polyhydric alcohol or a partial ester obtained by incorporating the crystal layer structure, the general formula _{MgxAly (OH) 2x + 3y-} z (a 2-) p (a - ) _q・ aZ ・ bH ₂ O (wherein A ²⁻ is a divalent anion such as CO ₃ ²⁻ , SO ₄ ²⁻ , A ⁻ is a perchlorate ion, Z is a polyhydric alcohol or a partial ester thereof,
x, y, z are Is a positive number satisfying and p and q are And a and b are Is a composite hydroxide or a dried or calcined product thereof.

As the polyhydric alcohol, any polyhydric alcohol is used, but a substantially non-volatile polyhydric alcohol, particularly a semi-solid to solid polyhydric alcohol is advantageously used. Suitable polyhydric alcohols include, for example, mono- and dipentaerythritol, other polypentaerythritol, mannitol, sorbitol, glucose, fructose, trimethylolpropane, polyethylene glycol (having a molecular weight of 200 to 9500), polypropylene glycol (for example a molecular weight of 1000 or more). , Polyoxypropylene-polyoxyethylene-block polymers (for example, those having a molecular weight of 1900 to 9000), polyhydric alcohols such as glycerin, pentaerythritol and sorbitol, and solid polyhydric compounds such as adducts of ethylene oxide or propylene oxide. Mention may be made of alcohol.

Instead of polyhydric alcohol, partial esters of polyhydric alcohol can also be used. That is, a compound obtained by esterifying a part of the hydroxyl groups of the above-mentioned polyhydric alcohol with a monobasic or polybasic carboxylic acid or a composition containing the same is used as a suitable partial ester, for example, mono- or mono- or Examples include di-pentaerythritol mono- or di-acetate, mono- or di-benzoate, mono-malate, mono-fumarate, mono-adipate, mono-sebacate, mono-succinate and the like. Of course, it is also possible to use a mixture of a polyhydric alcohol and a partial ester.

Examples of the styrene resin used in the present invention include polystyrene, methylstyrene mainly containing styrene, divinylbenzene, butadiene, acrylonitrile copolymer, acrylonitrile-butadiene-styrene terpolymer, acrylonitrile-butadiene-methyl. Examples thereof include a styrene terpolymer, a mixture of butadiene and styrene or acrylonitrile, and a mixture of styrene and acrylonitrile.

In the present invention, a halogen-based flame retardant of a polychlorinated organic compound and a polybrominated organic compound is used for flame retarding the styrene resin. Examples of polychlorinated organic compounds include perchloropentacyclodecane, tetrachlorophthalic anhydride, chloroendo acid, hexachloroethane, hexachlorohexane, and pentachlorobenzene, and examples of polybrominated organic compounds include tetrabromoethane. , Bromides of aliphatic hydrocarbons such as tetrabromobutane and tribromopropane, tribromotrichlorocyclohexane, tetrabromodichlorocyclohexane, pentabromocyclohexane, tetrabromocyclooctane, hexabromocyclododecane, bis (dibromocyclohexyl) -1,2 Alicyclic hydrocarbon bromide such as dibromoethane, hexabromobenzene, decabromodiphenyl, decabromodiphenyl ether, hexabromodiphenyl ether, pentabromo Phenyl ether, pentabromotoluene, pentabromoethylbenzene, pentabromophenol, tribromophenol, 1,2-dibromopropyltribromophenyl ether, tetrabromobisphenol A, tetrabromobisphenol S, tetrabromophthalic anhydride, 1,2-bis Aromatic bromides such as (pentabromophenoxy) ethane, bis (tribromophenoxy) ethane, polydibromophenylene oxide, and carbonate oligomers of tetrabromobisphenol A can be used.

The flame retardant resin of the present invention can be sufficiently heat-stabilized by adding perchlorate ion exchange-polyhydric alcohol-incorporated hydrotalcites, but when higher heat stabilization is required, dialkyl tin is used. The purpose can be achieved by further adding one or more of maleic acid salt, dialkyltin maleic acid ester salt, dialkyltin thiodipropionate or dialkyltin thiodipropionate.

Examples of the dialkyltin maleate include compounds of the general formula [1], and examples of dialkyltin maleate salts include compounds of the general formulas [2] and [3].

In the formula, R is an alkyl group such as a methyl group, a butyl group, an octyl group or a lauryl group, and R ¹ is a methyl group,
Ethyl group, butyl group, peptyl group, octyl group, isooctyl group, 2-ethylhexyl group, nonyl group, lauryl group, cetyl group, stearyl group, behenyl group, oleyl group, myristyl group, benzyl group, cyclohexyl group, methoxybutyl group , Hydrocarbon groups such as higher alkyl groups derived from higher alcohols synthesized by the oxo method, where n is 1
Each represents an integer of ~ 10.

As the dialkyltin thiodipropionate, for example, a compound having the repeating unit of the structure of the general formula [4] is used, and as the dialkyltin dithiodipropionate, for example, the structure of the general formula [5] is the repeating unit. Each of these compounds can be mentioned.

In the formula, R represents an alkyl group such as a methyl group, a butyl group, an octyl group and a lauryl group.

In the present invention, the addition amount of perchlorate ion exchange-polyhydric alcohol-incorporated hydrotalcites is 0.01 to 5 parts by weight with respect to 100 parts by weight of the styrene resin. If it is used below the lower limit of this amount, the thermal stability is not improved, and if it is above the upper limit, it is uneconomical. If higher thermal stability is required, one of dialkyltin maleate, dialkyltin maleate, dialkyltin thiodipropionate or dialkyltin dithiodipropionate can be used.
0.01 to 5 parts by weight may be added. If it is used below the lower limit of this amount, the thermal stability is not improved, and if it is above the upper limit, it is uneconomical.

In the composition of the present invention, if necessary, an antioxidant, an ultraviolet absorber, boric acid, a boric acid ester, an epoxy compound, a metallic soap, a diketone compound, a flame retardant other than a halogen-based compound (for example, a phosphorus compound, antimony trioxide, boron). Acid salt, aluminum hydroxide, etc.), smoke remover (smokeless agent), pigment, filler,
A lubricant or the like can be added.

[Action]

According to the present invention, perchlorate ion exchange-polyhydric alcohol-incorporated hydrotalcites obtained by contacting hydrotalcites with perchloric acid in the presence of water and polyhydric alcohol or its partial ester are added. By doing
Since the styrene resin containing halogen flame retardant can be highly heat-stabilized, it becomes easy to process the flame retardant resin at high temperature. When hydrotalcites that are not treated with perchloric acid and do not incorporate a polyhydric alcohol or a partial ester thereof are used, plate-out occurs during processing and the effect of the present invention cannot be achieved. By adding the dialkyltin compound of the present invention to perchlorate ion exchange-polyhydric alcohol-incorporated hydrotalcites, the thermal stability of the flame-retardant resin can be further improved.

〔Example〕

Next, the present invention will be described with reference to examples, but parts in the examples represent parts by weight.

Perchlorate Ion Exchange-Preparation of Polyhydric Alcohol-Incorporated Hydrotalcite Preparation 1 0.591 mol of commercially available synthetic hydrotalcite (DHT-4A, manufactured by Kyowa Chemical Industry Co., Ltd.) was dispersed in 3 l of methanol with stirring to prepare liquid A. To do. On the other hand, 0.394 mol of dipentaerythritol (manufactured by Koei Chemical Co., Ltd.) is dissolved in 0.518 mol of 70% aqueous solution of perchloric acid to prepare a solution B. Solution B was added to solution A with stirring, and stirring was continued until generation of carbon dioxide gas stopped. Thereafter, the pressure was reduced, and the cake was dried at 110 ° C. for 3 hours to obtain a sample A.

Preparations 2 to 7 Addition of solution B to solution A prepared in exactly the same manner as in preparation 1 except that 0.394 mol of dipentaerythritol was used instead of 0.394 mol of the polyhydric alcohol or its partial ester in Table 1, and the mixture was stirred and stirred. , And dried to obtain samples B to G.

These are summarized in Table 1.

Example 1 100 parts of acrylonitrile-butadiene-styrene resin (Cycolac Ex211, manufactured by Ube Cycon Co., Ltd.), 15 parts of tetrabromobisphenol A, 5 parts of antimony trioxide, and perchlorate ion exchange-polyhydric alcohol incorporation type shown in Table 2 below. 0.5 parts of hydrotalcite (Samples A, B, C and F) was added and mixed with a kneading roll at 150 ° C. for 4 minutes to prepare a sheet having a thickness of 0.5 mm. At this time, the plate-out property on the roll was observed. This sheet was sandwiched between aluminum plates and a thermal stability test was conducted in a gear oven maintained at 230 ° C. Further, the same test and observation were performed when 0.5 part of commercially available synthetic hydrotalcite (DHT-4A) was added and when 0.5 part of the mixture of synthetic hydrotalcite and polyhydric alcohol or its partial ester was added. .

The numbers and symbols in the table represent the following evaluations.

Thermal stability test 1: White color 2: Light yellow 3: Yellow color 4: Light brown 5: Brown 6: Black brown Plate-out property ○: No plate-out ×: Plate-out The results are shown in Table 2.

Example 2 100 parts of acrylonitrile butadiene styrene resin (Cycolac Ex211), 20 parts of a carbonate oligomer of tetrabromobisphenol A (Fireguard 7000, manufactured by Teijin Chemicals Ltd.), 8 parts of antimony trioxide, perchlorate ion exchange-many 0.3 part of hydrotalcite (Sample D) incorporating a hydric alcohol and 0.2 part of the organotin compound shown in Table 3 below were added and mixed by a kneading roll at 150 ° C. for 4 minutes to prepare a sheet having a thickness of 0.5 mm. This sheet was sandwiched between aluminum plates and a thermal stability test was conducted in a gear oven maintained at 230 ° C.

The numbers in the table have the same meaning as the evaluation in Example 1.

The results are shown in Table 3.

Example 3 100 parts of styrene resin (Styron 666, manufactured by Asahi Kasei), 15 parts of hexabromocyclododecane, 1 part of titanium oxide, and perchlorate ion exchange-polyhydric alcohol-incorporated hydrotalcite shown in Table 4 below (Sample B) , D, E and G) 0.5 part was added and mixed by a kneading roll at 130 ° C. for 3 minutes to prepare a sheet having a thickness of 0.5 mm. At this time, the plate-out property on the roll was observed. The sheet was subjected to a thermal stability test in a gear oven maintained at 220 ° C.

The numbers in the table represent the following evaluations, and the symbols have the same meanings as in Example 1.

1: White color 2: Light yellow 3: Yellow color 4: Light brown 5: Light black brown 6: Black brown The results are shown in Table 4.

Example 4 100 parts of styrene resin (Stylon 666), 10 parts of hexabromocyclododecane, 7 parts of antimony trioxide, 0.2 parts of perchlorate ion exchange-polyhydric alcohol-incorporated hydrotalcite (sample A) and Table 5 below. 0.5 part of the organotin compound was added and mixed with a kneading roll at 130 ° C for 3 minutes to form a sheet with a thickness of 0.5 mm. This sheet was subjected to a thermal stability test in a gear oven maintained at 230 ° C.

The numbers and evaluations in the table have the same meanings as in Example 3.

The results are shown in Table 5.

[Effects of the Invention] As is clear from the results of the thermal stability tests of Examples 1 to 4, in the present invention, perchlorate ion exchange-polyhydric alcohol-incorporated hydrogels are added to a styrene resin containing a halogen flame retardant. Addition of talcite or this and an organotin compound allowed the resin to be highly heat-stabilized and facilitated processing at high temperatures. Further, as is apparent from Examples 1 and 3, by adding perchlorate ion-exchange-polyhydric alcohol-incorporated hydrotalcite, a commercially available hydrotalcite or a mere mixture thereof with a polyhydric alcohol or a partial ester thereof is added. The drawbacks of the addition of
Plate out can now be prevented. Such an effect is first achieved by the present invention.

Claims (2)

[Claims] 1. When heat-stabilizing a flame-retardant resin comprising 100 parts by weight of a styrene-based resin and 1 to 50 parts by weight of a halogen-based flame-retardant, a general formula [1] Mg _x Al _y (OH) _{2x + 3y is used. -2z} (A ^2- ) _z · kH ₂ O [1] (In the formula, A ^2- is a divalent anion of CO ₃ ^2- or SO ₄ ^2- , and x, y, and z are 8
A positive number satisfying ≧ x / y ≧ 1/4 and z / (x + y)> 1/20, and k is a number satisfying 0.25 ≦ k / (x + y) ≦ 1.0) Anionic hydrotalcites and perchloric acid are brought into contact with each other in the presence of water and a polyhydric alcohol or a partial ester thereof, and 20 to 80% of divalent anions of hydrotalcites are converted to perchlorate ions. polyhydric alcohols or the general formula incorporated in the crystal layer structure in its partial esters with exchange (2) _{Mg x Al y (OH) 2x} + 3y-z (a 2-) p (a -) q · aZ · bH ₂ O [2] (In the formula, A ²⁻ is a divalent anion of CO ₃ ²⁻ or SO ₄ ²⁻ , A ⁻ is a perchlorate ion, Z is a polyhydric alcohol or its partial ester, and x, y, z are z = 2p + q, 8 ≧ x / y ≧ 1/4 and z / (x + y)>
It is a positive number that satisfies 1/20, and p and q are 1 ≧ q / (2p +
q) is a number satisfying ≧ 1/10, and a and b are 0.01 ≦ a /
(X + y) ≦ 1.0 and 0 ≦ b / (x + y) ≦ 1.0) represented by 0.01
A stabilized flame-retardant styrene-based resin composition, characterized by being added in an amount of up to 5 parts by weight. 2. When heat-stabilizing a flame-retardant resin comprising 100 parts by weight of a styrene-based resin and 1 to 50 parts by weight of a halogen-based flame-retardant, (a) the general formula [1] Mg _x Al _y (OH) _{2x + 3y-2z} (A ^2- ) _z · kH ₂ O [1] (In the formula, A ^2- is a divalent anion of CO ₃ ^2- or SO ₄ ^2- , and x, y, z are 8
A positive number satisfying ≧ x / y ≧ 1/4 and z / (x + y)> 1/20, and k is a number satisfying 0.25 ≦ k / (x + y) ≦ 1.0) Anionic hydrotalcites and perchloric acid are brought into contact with each other in the presence of water and a polyhydric alcohol or a partial ester thereof, and 20 to 80% of divalent anions of hydrotalcites are converted to perchlorate ions. polyhydric alcohols or the general formula incorporated in the crystal layer structure in its partial esters with exchange (2) _{Mg x Al y (OH) 2x} + 3y-z (a 2-) p (a -) q · aZ · bH ₂ O [2] (In the formula, A ²⁻ is a divalent anion of CO ₃ ²⁻ or SO ₄ ²⁻ , A ⁻ is a perchlorate ion, Z is a polyhydric alcohol or its partial ester, and x, y, z are z = 2p + q, 8 ≧ x / y ≧ 1/4 and z / (x + y)>
It is a positive number that satisfies 1/20, and p and q are 1 ≧ q / (2p +
q) is a number satisfying ≧ 1/10, and a and b are 0.01 ≦ a /
(X + y) ≦ 1.0 and 0 ≦ b / (x + y) ≦ 1.0) represented by 0.01
To 5 parts by weight and (b) 0.01 to 5 parts by weight of one or more of dialkyltin maleate, dialkyltin maleate, dialkyltin thiodipropionate or dialkyltin dithiodipropionate. Stabilized flame-retardant styrene-based resin composition, characterized in that