JPH0261508B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a flame retardant for synthetic resins that has excellent heat resistance. In recent years, there has been a growing demand for flame retardant properties in synthetic resin products, mainly for housing interior materials, electrical and electronic equipment, etc., and a large number of flame retardants have been developed for this purpose. This type of flame retardant is mainly halogen-based or phosphorus-based, but phosphorus-based ones in particular have problems with bleeding, heat resistance, and water resistance, probably because they use relatively low molecular weight phosphoric acid compounds. Ta. The present invention eliminates these drawbacks and provides a phosphorus-containing organic flame retardant that can be stably used in synthetic resins in general. The flame retardant of the present invention comprises a phenol formaldehyde condensate and an organic phosphorous acid monohalodate represented by the general formula K0070 (wherein R ₁ and R ₂ represent a haloalkyl group having 1 to 8 carbon atoms, and X represents Cl or Br). The phosphorous acid ester component is characterized in that it is obtained by condensing the phosphorous acid ester component with the phosphorous acid ester component, and then converting at least a part of the phosphorous acid ester component into a phosphonate by heating. A phenol-formaldehyde condensate is obtained by reacting phenols and formaldehyde (formalin, paraformaldehyde, etc.) under an acidic or alkaline catalyst. , propylphenol, butylphenol, amylphenol, nonylphenol, phenylphenol, phenylphenol ether, phenoxyphenol, styrenated phenol, monobrominated styrenated phenol, hydroquinone, resorcinol, dihydroxydiphenyl, bis(hydroxyphenyl) ) pentane, dihydroxydiphenylmethane, bis(hydroxyphenyl)butane, dihydroxydiphenyl sulfone, dihydroxydiphenylketone, bis(hydroxyphenyl)propane, methylenebis(ethyltertiary butyl cresol) and mixtures thereof. It will be done. In the present invention, the average degree of condensation of the phenol formaldehyde condensate is preferably 2 to 15,
In particular, it is more preferably 2 to 10. Further, the ratio of phenols and formaldehyde used in the production thereof is preferably 0.6 to 2.5 mols of formaldehyde per 1 mol of phenol. If the amount of formaldehyde is less than 0.6 mol per 1 mol of phenol, there will be problems with the heat resistance and bleedability of the compound produced by the reaction with the organic phosphorous monohalodate, and if it exceeds 2.6 mol, the organic phosphorous monohalodate will It is impractical because gelation tends to occur during the reaction with. Next, examples of the organic phosphorous monohalodate represented by the general formula (1) include di(chloroethyl) phosphorous monochloridate, di(bromoethyl) phosphorous monochloridate, di(chloropropyl) phosphorous monochloridate, Bis(dibromopropyl)
Monochloridate phosphite, di(bromoethyl) monobromidate phosphite, di(bromopropyl) monobromidate phosphite, bis(dibromopropyl) monobromidate phosphite, and mixtures thereof are used. The flame retardant of the present invention is prepared by preparing a phenolic resin and an organic phosphite monohalodate in approximately equimolar amounts, heating the mixture preferably in a nitrogen stream, and converting it into a phosphite ester compound through a dehydrohalogenation reaction.
It is obtained by heating at 100 to 250°C, preferably 150 to 200°C to phosphonate at least a part of the phosphite component. The phosphonatization reaction is completed by heating for about 10 to 20 hours;
A sufficient effect can be obtained without converting everything to phosphonate, and generally the phosphonate rate is 50%.
% or more is practical. Phosphonation rate is the difference between P-OCH ₂ and P-CH ₂
This can be confirmed by tracking the proton ratio in the ^1HNMR spectrum. The method for applying the flame retardant of the present invention to synthetic resin includes:
The same addition method as usual can be adopted, and it is also possible to use it in combination with other flame retardants, such as antimony trioxide, organic halogen-containing compounds, and phosphoric acid compounds.
Examples of organic halogen-containing compounds include halogenated phenols, halogenated bisphenols, halogenated diphenyl ethers, and halogenated polyphenyls, and phosphoric acid compounds include tricresyl phosphate, triphenyl phosphate, and cresyl diphenyl phosphate. and so on. Since the flame retardant of the present invention contains halogen and phosphorus as flame-retardant atoms in the same molecule, it has an excellent flame-retardant effect, and it also has a phosphonate skeleton in the molecule, which could not be used in the past mainly due to economic reasons, at a low cost. Therefore, the water resistance and heat resistance of the phosphonate are also taken into consideration. Note that the flame retardant of the present invention can be effectively used for both thermosetting resins and thermoplastic resins. These resins include, for example, phenolic resins, urea resins,
Melamine resin, polyester resin, silicone resin, acrylic resin, polystyrene resin, polyethylene resin, polypropylene resin, AS resin, ABS
Includes resins, polyvinyl chloride resins, etc. Next, examples of the present invention will be shown. In the examples, parts and % indicate parts by weight and % by weight unless otherwise specified. Example 1 In a reactor equipped with a stirrer and a reflux condenser, 94 parts of phenol, 81.1 parts of 37% formalin and 35% as a catalyst were added.
% hydrochloric acid was added and stirred at 90-100°C for 90 minutes. 322.5 parts of bis(2,3-dichloropropyl)phosphorous acid chloridate was added to the obtained phenol formaldehyde condensate with stirring, and dehydrochlorination was carried out at 100°C for 3 hours in a N ₂ stream to dissolve the phenol formaldehyde condensate. A phosphorous acid ester compound was obtained. This compound was heated to 180° C. and stirred at the same temperature for 6 hours, and then the phosphonate conversion rate of the compound was measured by ¹ H NMR spectrum. The phosphonate conversion rate was about 80%. This product is called A. Products B to G were obtained in the same manner as A except that the amounts of phenols and 37% formalin were varied and the ingredients shown in Table 1 were used. Table 1 shows the phosphonate conversion rate of each product.

[Table] * Comparative Example Example 2 Flame retardants shown in Table 2 were added to 100 parts of styrene resin, and kneaded at 140-150°C for 5 minutes using a hot roll. The resulting mixture is then heated to 140~
After pressurizing at 160°C and 150 atm for 3 minutes, it was placed in a screw press for cooling. The plastic sheet taken out from the cooling screw press is ASTM-D
It was cut according to the method described in -635-56T, a test piece (127 mm x 12.7 mm x 1.5 mm) was prepared, and the following tests were conducted. The results are shown in Table 2. Combustion test: ASTM D635-56T Heat deformation test: JIS K7207 Heat resistance test: Examine coloring after being left in air at 180°C for 3 hours.

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[Table] Example 3 To 100 parts of the resin shown in Table 3, 10 parts of the flame retardant obtained in Example 1 was added and kneaded for 5 minutes using hot rolls at a predetermined temperature. The obtained mixture was pressure-molded using a heating compressor at 150 atmospheres for 5 minutes. Flammability of each molded product was measured using the UL-94 (1/8 inch) test method. The results are shown in Table 3.

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Claims (1)

[Scope of Claims] 1. A phenol formaldehyde condensate and an organic phosphorous acid monohalodate represented by the general formula K0069 (wherein R ₁ and R ₂ represent a haloalkyl group having 1 to 8 carbon atoms, and X represents Cl or Br). 1. A flame retardant for synthetic resins, characterized in that it is obtained by condensing the phosphite component with the phosphite component, and then converting at least a part of the phosphite component into a phosphonate by heating.