Polyester compositions, shaped articles obtained from them and processes for preparing them
AssigneeImperial Chemical Industries PLC
InventorPatrick J. Horner
Life of this patent
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Abstract
UV stable linear polyesters, e.g. PET, contain in their chain copolymerized bis(hydroxyalkoxy)xanth-9-ones, preferably 3,6-bis-(2-hydroxyethoxy)xanth -9-ones. The polymers are obtained by polymerization in the presence of a tetrahydroxy benzophenone, preferably the 2,2',4,4'- isomer. The method of polymerizing in the presence of dihydric phenols to obtain ethoxyaryloxy polyesters is also described.
Claims7
A linear polyester which contains polymerized in its molecule polymerized units of bis(hydroxyalkoxy)xanth-9-ones, the amount of said bis(hydroxyalkoxy)xanth-9-ones being 0.05 to 10% by weight based on the total polymer.
A linear polyester which has an IV above 0.50 and which contains in its molecule polymerized units of:
- (A) Dicarboxylic acids selected from
- (i) terephthalic acid,
- (ii) isothphthalic acid,
- (ii) naphthalene-2,6-dicarboxylic acid, and
- (iv) bis(carboxyphenoxy)ethane,
- (B) Glycols with 2 to 10 carbon atoms in the molecule,
- (C) Bis(hydroxyalkoxy)xanth-9-ones,
- (D) 2,4-dihydroxybenzoic acid,
- the amount of (C) being 0.05 to 10% and the amount of (D) being 0 to 10%, both percentages being by weight and based on the amount of (A)+(B)+(C)+(D).
A linear polyester which has as repeating units:
- --OYO--CO--X--CO--
- wherein
- at least 80 mole % of the X-groups represent p-phenylene and the remainder represent m-phenylene
- at least 90% of the Y groups represent C.sub.2 H.sub.4 and at least 0.1% of the Y groups represent polymerized units of 3,6-bis(hydroxyethoxy)xanth-9-one.
Dependencies are inferred from the claim text.