| abstract |
There is disclosed a method for the production of aliphatic copolyester films. The method comprises the steps of: n applying esterification or ester-interchange at below 220°C to a reaction mixture ofn an acid component selected from the group consisting of succinic acid, succinic anhydride and succinic acid ester, 1,4-butanediol as a diol component, 2,2-dimethyl-1,3-propanediol of 1 to 30% by mole based on the mole of the acid component, at least one multifunctional compound of 0.01 to 1% by mole based on the mole of the acid component , said multifunctional compound having at least three functional groups - identical or different - selected from hydroxy and carboxy groups; polycondensing the oligomer into an aliphatic copolyester at a temperature of 240 to 260°C under reduced pressure of not more than 133.3 Pa (1 mmHg) in the presence of a catalyst; and n melt-extruding the aliphatic copolyester using T die.n Improved in draw ratio, the aliphatic copolyester film provided by the method can be applied to various applications, such as films, bottles, glass fiber-reinforced plastics, adhesives, paints. |