Process for the preparation of polyester resin
AssigneeSinco Ricerche S.p.A.
InventorsHussain Al Ghatta, Enrico Ballico, Arianna Giovannini
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Abstract
A process for the preparation of aromatic polyester resins, in which the resin obtained from the polycondensation phase in the molten state conducted by utilizing a titanium based compound as a catalyst, is subjected to a solid state polycondensation reaction in the presence of a dianhydride of a tetracarboxylic acid.
Claims8
A process for the preparation of polyester resins having an intrinsic viscosity greater than 0.7 dl/g starting from resins with an intrinsic viscosity of 0.2-0.7 dl/g obtained by polycondensation of diols with 2-12 carbon atoms and aromatic dicarboxylic acids or by transesterification of the lower alkyl esters of the dicarboxylic acids and subsequent polycondensation, using in the polycondensation phase a catalyst comprising a titanium compound, wherein the polyester resin obtained from the polycondensation is added with a dianhydride of a tetracarboxylic acid and subsequently subjected to solid state polycondensation to obtain an intrinsic viscosity increase of at least 0.1 dl/g.
Dependencies are inferred from the claim text.