| 摘要 |
1442681 Treating polypropylene CHEMIE LINZ AG 12 July 1973 [25 July 1972] 33384/73 Heading C3P Polypropylene having a narrow molecular weight distribution is prepared by treating fused polypropylene stabilized with a phenolic antioxidant and optionally a phenolic light stabilizer, with 0À005 to 0À5 weight per cent of a free radical forming agent selected from 2,5- dimethyl - 2,5 - di(t - butylperoxy)hexyne - 3, 1,3 - bis - (t - butylperoxyisopropyl) benzene, 3,3,6,6,9,9 - hexamethyl cyclo - 1,2,4,5, - tetraoxanonane, 2,5 - dimethyl - 2,5 - di(t-butylperoxy)hexane or a phthalide peroxide, for at least 10 seconds at 180‹ to 300‹ C. The antioxidant may be a pentaerythritol or octadecanol ester of 3,5-di-t-butyl-4-hydroxyphenylpropionic acid, 1,3,5-trimethyl-2,4,6-tri(3<SP>1</SP>,5<SP>1</SP>-di-tbutyl - 4<SP>1</SP> - hydroxyphenyl)benzene, 4 - hydroxymethyl - 2,6 - di - t - butylphenol, tris- (2<SP>1</SP> - methyl - 4<SP>1</SP> - hydroxy - 5<SP>1</SP> - t - butylphenyl)butane, 2,6 - di - t - butyl - pcresol, 3,5 - dimethyl - 4 - hydroxybenzyl glycolic acid stearyl ester or the 2 : 1 nickel complex of monoethyl 3,5-di-t-butyl-4-hydroxybenzyl phosphonate. The light stabilizer may be 2-(2<SP>1</SP>-hydroxy- 3<SP>1</SP>,5<SP>1</SP> - di - t - amylphenyl)benzotriazole, 2- (2<SP>1</SP> - hydroxy - 3<SP>1</SP>,5<SP>1</SP> - di - t - butylphenyl) - 5- chlorobenzotriazole or 2 - hydroxy - 4 - noctoxybenzophenone. Synergistic sulphur containing stabilizers, e.g. distearyl and dilauryl thiodipropionates, may also be present. The reaction may be effected in a screw injection moulding machine or kneader. |
