Polyoxalate copolymer and method of producing the same
AssigneeToyo Seikan Group Holdings, Ltd.
InventorsTsutaki KATAYAMA, Seishi YOSHIKAWA
Life of this patent
Estimating the term…
Abstract
A polyoxalate copolymer including an acid-constituting unit derived from an oxalic acid and a diol-constituting unit derived from a diol component, the diol-constituting unit being derived from a combination of an ethylene glycol and other diols, and having a temperature differential between a 5% weight loss temperature as measured by the TG-DTA and a melting point thereof in a range of 50 to 80° C.
Claims6
A polyoxalate copolymer including an acid-constituting unit derived from an oxalic acid and a diol-constituting unit derived from a diol component, the diol-constituting unit being derived from a combination of an ethylene glycol and other diol, and having a temperature differential between a 5% weight loss temperature as measured by the TG-DTA and a melting point thereof in a range of 50 to 80° C.
A method of producing a polyoxalate copolymer by using, as a diol component, an ethylene glycol and other diol in combination, and subjecting the diol component and a dimethyl oxalate to an esterification polymerization reaction, wherein:
- the esterification polymerization reaction is executed through a step that includes:
- a step of a normal-pressure polymerization inclusive of the esterification polymerization reaction of a oxalic acid formed from the dimethyl oxalate and the ethylene glycol, and
- a step of a reduced-pressure polymerization that is accompanied by a removal of diol after the step of the normal-pressure polymerization;
- and wherein;
- the other diol is added to a polymerization system at a predetermined temperature in the step of the normal-pressure polymerization.
Dependencies are inferred from the claim text.