Light-stable modified polyethylene terephthalate prepn. by di:methyl terephthalate alcoholysis with ethylene glycol in presence of 1,1'-di:acyl-ferrocene

摘要

Light-stable, colour-fast modified polyethylene terephthalate is of formula (where A is (i): R is 1-4C alkyl; m= 0.9996-0.9830; n= 0.0004-0.0070; m + n= 1; p= 50-100). (I) is prepd. by (a) alcoholysis of dimethyl terephthalate with ethylene glycol at 150-225 degrees C in the presence of 0.05-1 wt. % 1,1'-diacylferrocene, and then (b) polycondensation of prod. at 275-290 degrees C under residual pressure 0.5-1 Torr. S and-coloured to brown fibres and films are prepd. from (I). Addn. of a 1,1'-diacyl-ferrocene (II) as modifier improves light stability of polyethylene terephthalate. E.g. incorporation of 0.05 wt. % (II) improves fibre breaking strength from 16.4 to 24.2 g/tex after Uv. irradiation for 10 days at 40 degrees C and 80% RH. (II) also acts as catalyst for alcoholysis of dimethyl terephthalate with ethylene glycol and dyes the polymer sand-coloured to brown. Modified polyethylene terephthalate prepn. comprised dimethyl terephthalate and ethylene glycol alcoholysis with addn. of 0.05-1 wt. % 1,1'-diacetyl-ferrocene.