JPH0458469B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention discloses 2,2'-methylenebis(4-tert-octyl-6-benzotriazolylphenol) useful as a light stabilizer for organic materials such as synthetic polymers.
It provides: 2-Hydroxyphenylbenzotriazole compounds are known to be light stabilizers for various organic materials such as synthetic resins, but because of their low molecular weight, they may volatilize during resin processing or The organic substances were extracted from the resin by water, organic solvents, etc., and as a result, the organic substances could not be stabilized for a long period of time. For this reason, it has been proposed to introduce large substituents or to dimerize the compound with aldehydes. For example, Japanese Patent Publication No. 55-39180 describes dimerization with higher aldehydes, and Japanese Patent Publication No. 49-61071 describes dimerization with specific bonds. The publication also describes methylenebis(benzotriazolylphenol). However, the effects of these compounds are still not fully satisfactory, and there has been a demand for compounds with even better photostabilizing effects. The inventors of the present invention have made intensive studies to obtain a compound with excellent photostabilizing effect and good heat resistance and extraction resistance. The inventors have discovered that octyl-6-benzotriazolylphenol) can solve all of the above problems and have arrived at the present invention. The above compound can be produced by, for example, dimerizing 2-benzotriazolyl-4-tertiary octylphenol with formaldehydes, or converting 2,2'-methylenebis(4-tertiary octylphenol) into benzotriazolyl by a conventional method. It can be easily manufactured by a method such as oxidation. The 2,2'-methylenebis(4-tert-octyl-6-benzotriazolylphenol) of the present invention is useful as a light stabilizer for organic materials such as various synthetic resins, rubbers, waxes, oils and fats. Examples of the organic material stabilized by the compound of the present invention include α-olefin polymers such as polyethylene, polypropylene, polybutene-1, poly-3-methylpentene, ethylene-vinyl acetate copolymers, ethylene-propylene copolymers, etc. α-olefin copolymers such as polymers, polyvinyl chloride,
Polyvinyl bromide, polyvinyl fluoride, polyvinylidene chloride, chlorinated polyethylene, chlorinated polypropylene, polyvinylidene fluoride, chlorinated rubber, vinyl chloride-vinyl acetate copolymer, vinyl chloride-ethylene copolymer, vinyl chloride Halogen-containing resins such as vinylidene chloride copolymer, vinyl chloride-urethane copolymer, petroleum resin, coumaron resin, polystyrene, polyvinyl acetate, acrylic resin, methacrylic resin, polyacrylonitrile, styrene and other monomers (e.g. anhydrous (maleic acid, butadiene, acrylonitrile, etc.), acrylonitrile-butadiene-styrene terpolymer, methacrylic acid ester-butadiene-styrene terpolymer, polyvinyl alcohol, polyvinyl butyral, polyethylene terephthalate, polybutylene terephthalate , linear polyester or polyether ester such as polytetramethylene ether glycol terephthalate, polyphenylene oxide, polyamide, polycarbonate, polyacetal, polyurethane, cellulose resin, phenolic resin, urea resin, melamine resin, epoxy resin, unsaturated polyester polymeric substances such as resins, silicone resins, isoprene rubber, butadiene rubber, acrylonitrile-butadiene rubber, styrene-butadiene rubber, and blends thereof;
Examples include natural oils and fats, synthetic ester oils, and mineral oils. The present invention will be explained in more detail with reference to the following examples, but the present invention is not limited by these examples. Example 1 2,2'-methylenebis(4-tert-octyl-6
32.3 g of 2-benzotriazolyl-4-tertiary octylphenol, 11.0 g of diethylamine and 5.2 g of paraformaldehyde were dissolved in 25 ml of butanol and stirred under reflux for 24 hours. Thereafter, the solvent was removed under reduced pressure to obtain 39.2 g of 2-diethylaminomethyl-4-tert-octyl-6-benzotriazolylphenol. 37 g of the above product and 2-benzotriazolyl-
25g of 4-tertiary octylphenol and 60ml of xylene
3.1 g of sodium methoxide (28% methanol solution) was added. The mixture was stirred under reflux for 10 hours while bubbling nitrogen gas, and then the solvent was removed under reduced pressure to obtain 55.2 g of a crude product, which was recrystallized from n-heptane to give a product with a melting point of 200.
℃ white crystals were obtained. The above product was dissolved in deuterated chloroform and NMR
When measured, there was a singlet line at a δ value of 4.9, confirming that it was the target object. Example 2 In order to examine the excellent photostabilizing effect of the compound of the present invention, a press sheet with a thickness of 0.3 mm was prepared using the following formulation, and a light resistance test was conducted on this sheet using a high-pressure mercury lamp. In addition, 48% in hot water at 80℃
A light resistance test was also conducted on the sheet after being immersed for a period of time. The results are shown in Table-1. [Formulation] Polypropylene 100 parts by weight Calcium stearate 0.2 Pentaerythritol tetrakis (3,5-di-tert-butyl-4-hydroxyphenyl) propionate 0.1 Stabilizer (see Table 1) 0.2

【table】

[Table] Example 3 The compound of the present invention has excellent heat resistance,
Its effectiveness remains unchanged even under harsh processing conditions. In this example, the effect of repeating extrusion processing at high temperatures was examined. The resin and additives were mixed in a mixer for 5 minutes according to the following formulation, and then a compound was prepared in an extruder (cylinder temperature 230°C and 240°C, head die temperature 250°C, rotation speed 20 rpm). After repeating extrusion five times, test pieces were made using this compound using an injection molding machine (cylinder temperature 240°C, nozzle temperature 250°C, injection pressure 475°C).
kg/ ^cm2 ). A light resistance test was conducted using the obtained test piece using a high-pressure mercury lamp. In addition, a light resistance test was also conducted on a test piece using a compound that had been extruded once. The results are shown in Table-2. [Formulation] Ethylene-propylene copolymer resin 100 parts by weight Calcium stearate 0.2 Stearyl-3,5-di-tert-butyl-4-hydroxyphenylpropionate 0.1 Dilaurylthiodipropionate 0.2 Stabilizer (see Table 2) 0.2

[Table] From the results in Tables 1 and 2, the compound of the present invention has a significantly greater photostabilizing effect than monomeric benzotriazolylphenol and similar dimeric compounds, and has excellent extraction resistance and It is clear that it has excellent heat resistance.

Claims (1)

[Scope of Claims] 1 2,2'-methylenebis(4
-tertiary octyl-6-benzotriazolylphenol).