摘要:
Disclosed is a method for preparing polyester resins copolymerized with glycol for modification such as 1,4-cyclohexanedimethanol, in which the content of said glycol ingredient for modification ranges from 20 to 80 mol % of the total glycol content. Dicarboxylic acid such as terephthalic acid is esterified with ethylene glycol and said glycol for modification. The esterification product is subjected to polycondensation in the presence of a titanium dioxide/silicon dioxide coprecipitate catalyst, said catalyst being in the form of 4% or less strength by weight suspension in glycol. The copolyester prepared as above shows excellent transparency and color properties in addition to being produced at high efficiency.
摘要:
Disclosed is a method for preparing polyester resins copolymerized with 1,4-cyclohexanedimethanol. In the preparation method, ethylene glycol and 1,4-cyclohexanedimethanol are fed with the molar ratio of the whole glycol component to terephthalic acid ranging from 1.3 to 3.0, and then esterified. Then, the esterified reaction product is polycondensed in the presence of titanium-based compound as a polycondensation catalyst and carboxy phosphonic acid typed compound represented by formula I below as a stabilizer, to give the polyester resins of the present invention having excellent clarity and good color: wherein R1, R2 and R3, which are the same or different, each being selected from the group consisting of hydrogen, alkyl groups having 1 to 10 carbon atoms, cycloalkyl groups having 1 to 10 carbon atoms and aryl groups having 6 to 10 carbon atoms; and R is selected from the group consisting of alkylene groups having 1 to 10 carbon atoms, cycloalkylene groups having 1 to 10 carbon atoms, and arylene groups having 6 to 10 carbon atoms.