JPS6234784B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a flame-retardant styrenic composition with excellent heat resistance. Due to its excellent processability, styrene resin is used in large quantities as a molding or foaming material for a wide variety of applications such as electrical appliances, interior decoration, building materials, insulation materials, cushioning materials for heavy objects, and structures. There is. In recent years, with the tightening of various flame retardant regulations such as regulations on the storage of combustible plastics, better flame retardancy is required, and on the other hand, improvements in the physical properties of resins have particularly increased mechanical strength, making them lighter and saving resources. Consideration is underway to change the A method of using hexabromocyclododecane to make styrene resin flame retardant was published in 1973.
-Described in Publication No. 16837. When hexabromocyclododecane is used as a flame retardant for styrenic resins, as described in the same publication, it is necessary to
Suitable for use at relatively low temperatures such as: On the other hand, when used in injection molding, extrusion molding, etc., a temperature condition of 180°C to 220°C is generally required, and the heat resistance of hexabromocyclododecane poses a problem. For example, when increasing the amount of hexabromocyclododecane added to obtain a flame-retardant styrenic resin molded product that complies with various flame-retardant regulations by injection molding or extrusion molding, the thermal decomposition during molding is particularly important. Due to the generation of hydrogen bromide, the depolymerization of the styrene resin base material is accelerated, the physical properties of the resin are deteriorated, and the resin molded product is significantly colored. Therefore, in order to improve the heat resistance of hexabromocyclododecane, a method of using hexabromocyclododecane or a mixture thereof in combination with an organotin compound and an organophosphorus compound is described in JP-A-56-145939, and is an excellent method. Although it is effective,
Recently, resin modification etc. have been carried out to further increase the heat resistance of styrene resin base materials, and in order to prevent deterioration of resin flow due to resin modification, the temperature condition during molding is 230 ° C or higher, and There is a tendency for flame-retardant styrenic resin compositions to be used in places exposed to high temperatures during practical use. Even if the above method is applied under such circumstances, it is not possible to obtain results that sufficiently improve the prevention of coloring or deterioration of physical properties of flame-retardant styrenic resin compositions or molded products thereof. This is the reality. The present inventors have conducted intensive research to improve the above-mentioned drawbacks, and as a result, they have now provided the present invention. That is, (a) hexabromocyclododecane or a mixture of hexabromocyclododecane and halogenated aromatic allyl ether as a flame retardant, (b) an organotin compound, and (c) an organophosphorus compound blended into a styrene resin. This flame-retardant styrenic resin composition has excellent heat resistance and is characterized by containing an epoxy compound as a stabilizer. Epoxy compounds used as stabilizers in the present invention include, for example, phenyl glycidyl ether, tribromophenyl glycidyl ether, dibromophenyl glycidyl ether, monobromophenyl glycidyl ether, cresyl glycidyl ether, 2,2-
Glycidyl ether of bis(4-oxyphenyl)propane, glycidyl ether of 2,2-bis(4-oxyphenyl)sulfone, glycidyl ether of phenol novolak, propyl glycidyl ether, butyl glycidyl ether, glycidyl ether of ethylene glycol, glycidyl ether of polypropylene glycol. Examples thereof include glycidyl ether, glycidyl ether of glycerin, glycidyl ether of cyclohexanol, glycidyl ester of cyanuric acid, and condensates thereof. The blending amount of the epoxy compound is the total amount of the epoxy compound, organotin compound, and organophosphorus compound, and is 0.4 to 20% by weight with respect to the blending amount of the flame retardant, and the blending ratio of the epoxy compound in the total amount is Epoxy compound: (organotin compound+organophosphorus compound)=1-10:10-1. Next, examples of the flame retardant include hexabromocyclododecane alone or a mixture of hexabromocyclododecane and halogenated aromatic allyl ether. Examples of hexabromocyclododecane include those obtained by known methods.
Examples of the halogenated aromatic allyl ether used in combination with hexabromocyclododecane in the mixture include tribromphenyl allyl ether, trichlorophenyl allyl ether, pentabromphenyl allyl ether, and bis(allyloxybromphenyl)propane. , bis(aryloxydibromophenyl)propane, bis(aryloxydibromophenyl)methane, 2(2-bromoethoxydibromophenyl)-2(aryloxydibromophenyl)propane, and other halogenated aromatics. Examples include allyl ethers and mixtures thereof. The mixing ratio (weight) of hexabromocyclododecane and halogenated aromatic allyl ether in the mixture is 1:1, or the amount of halogenated aromatic allyl ether is smaller than that of hexabromocyclododecane. When the amount of halogenated aromatic allyl ether is greater than that of hexabromocyclododecane,
The object of the invention is not achieved. The amount of the flame retardant to be blended is 0.5 to 20 parts by weight, preferably 0.5 to 10 parts by weight, per 100 parts by weight of the styrene resin. Examples of organic tin compounds include di-n-octyltin malate polymer, monobutyltin trioctyl maleate, dibutyltin dioleyl maleate,
Aliphatic tin compounds such as dibutyltin methoxymethyl malate, dibutyltin dioctyl thioglycolate, dibutyltin diurarate, aromatic tin compounds such as tribenzyltin octyl maleate, and fats such as dibutyltin diuralyl mercaptide. Examples include tin mercaptide compounds or mixtures thereof. Examples of organic phosphorus compounds include isopropylidene diphenol decyl phosphite, isopropylidene diphenol dodecyl phosphite, isopropylidene diphenol pentadecyl phosphite, isopropylidene diphenol octadecyl phosphite, diphenol isooctyl phosphite, and diphenol isooctyl phosphite. Diaryl monoalkyl phosphite such as phenolisodecyl phosphite, triethyl phosphite, tricresyl phosphite, triisodecyl phosphite, trioleyl phosphite,
Trialkyl phosphites such as triethylhexyl phosphite, dialkyl monoaryl phosphites such as dioctyl phenyl phosphite, triaryl phosphites such as diphenylnonylphenyl phosphite and tricylenyl phosphite, trischloroethyl phosphite, etc. trihalogenated alkyl phosphites or mixtures thereof. The amount of the organic tin compound and the organic phosphorus compound is the total amount of the epoxy compound, the organic tin compound, and the organic phosphorus compound, and is 0.4 to 20% by weight based on the amount of flame retardant. The blending ratio of the organotin compound and the organophosphorus compound is epoxy compound: (organotin compound + organophosphorus compound) = 1 to 10:10 to 1, and the ratio of the organotin compound and the organophosphorus compound is The blending ratio is organotin compound:organophosphorus compound=10
~1:1~10. In the present invention, an organotin compound and/or
Alternatively, if an organic phosphorus compound is used, the object of the present invention will not be achieved. Next, as styrene resin, styrene, α-
Methylstyrene, chlorostyrene, dichlorostyrene, bromostyrene, dimethylstyrene, t-
Homopolymers of styrene derivatives such as butylstyrene and vinyltoluene, or copolymers of combinations thereof, or copolymers of styrene derivatives with olefinic compounds such as divinylbenzene, methyl methacrylate, acrylonitrile, or butadiene, etc. etc. Note that additives such as coloring agents, spreading agents, ultraviolet absorbers, and blowing agents used during molding can be used in the present invention in the amounts normally used. According to the present invention, in injection molding or extrusion molding, not only flame retardance but also excellent heat resistance,
A resin molded product of a styrene resin composition that is free from coloring and exhibits little deterioration in physical properties can be obtained. Examples of the present invention are listed below. Example 1 A flame retardant, an organic tin compound, and an organic phosphorus compound were added to styrene resin (S-Brite-8, manufactured by Sumitomo Chemical KK), and an epoxy compound was further added, and the mixture was kneaded at 200°C for 6 minutes using a hot roll. .
Next, the obtained mixture was pressed at 200° C. and 200 atm for 3 minutes, and then applied to a screw press for cooling. Next, it was taken out from a cooling screw press to obtain a plastic sheet. Using this plastic sheet, color change, flame retardancy, physical properties, heat resistance, etc. were measured. Comparative examples were also carried out in the same manner. The results are shown in Table 1. Example 2 A flame retardant, an organic tin compound, an organic phosphorus compound, and an organic phosphorus compound were added to styrene resin (Estyrene H1-H61, manufactured by Nippon Steel Chemical Industry KK) and heated at 200 to 210°C using a hot roll. The mixture was kneaded for 6 minutes. Next, the obtained mixture is pressed at 190-200°C and 200 atm for 3 minutes, and then applied to a screw press for cooling. A plastic sheet was obtained from the cooling screw press. Using this plastic sheet, color change, flame retardancy, and physical properties were measured. Comparative examples were also carried out in the same manner. The results are shown in Table 2.

【table】

【table】

【table】

Claims (1)

[Scope of Claims] 1. A flame-retardant styrenic resin composition in which (a) hexabromcyclododecane as a flame retardant, (b) an organotin compound, and (c) an organophosphorus compound are blended into a styrene resin. , a flame-retardant styrenic resin composition with excellent heat resistance, characterized in that it contains an epoxy compound as a stabilizer. 2. Flame-retardant styrenic resin containing (a) a mixture of hexabromocyclododecane and halogenated aromatic allyl ether as a flame retardant, (b) an organotin compound, and (c) an organophosphorus compound in a styrene resin. A flame-retardant styrenic resin composition with excellent heat resistance, characterized in that the resin composition contains an epoxy compound as a stabilizer.