| 摘要 |
1,155,005. Poly (glycol terephthalates). TEIJIN Ltd. 19 Aug., 1966 [21 Aug., 1965], No. 37345/66. Heading C3R. In the manufacture of poly (glycol terephthalates) by reacting a glycol with terephthalic acid or an alkyl ester thereof to produce a diglycol ester of terephthalic acid or an oligomer thereof which is thereafter polycondensed, the polycondensation reaction is effected in the presence of (a) a catalyst which is a cerium or lanthanum compound ; and (b) a colour stabilizer which is a phosphorus compound of formula wherein R 1 is an aralkyl radical, R 2 and R 3 are hydrogen atoms or alkyl, cycloalkyl or aryl groups and wherein R 1 , R 2 and R 3 may be substituted by hydroxyl, carboxyl, alkoxycarbonyl or hydroxyalkyl groups. Specified catalysts are cerium (III or IV) and lanthanum acetates, oxalates, malonates, citrates, benzoates, terephthalates, nitrates, borates, carbonates, chlorides, bromides, alcoholates (e.g. of ethylene glycol) and hydroxides and in one example a mixture of the acetates of cerium, lanthanum, neodymium and other lanthamide elements. Antimony oxide may be used as an additional polycondensation catalyst. The glycol may be ethylene glycol, trimethylene glycol, hexamethylene glycol, neopentylene glycol, 1: 4- cyclohexanedimethanol, 1:4 - bis(hydroxyethoxy) benzene or 2: 2: 4: 4-tetramethylcyclobutanediol-1: 3. Part of the terephthalic acid may be replaced by other dicarboxylic acids or hydroxycarboxylic acids. Chain-terminating agents or chain-branching agents may also be included. Examples describe the manufacture of polyesters by reacting ethylene glycol with terephthalic acid, dimethyl terephthalate or a mixture of dimethyl terephthalate and dimethyl isophthalate. Reference has been directed by the Comptroller to Specification 819,640. |
