초록

Dopes from which shaped articles of oxadiazole/N-alkylhydrazide copolymers are provided. The dopes are prepared in a matter of minutes by combining and mixing a slurry of aromatic dihydrazide in aromatic diester with a mineral acid such as oleum.

대표청구항 ▼

A process for preparing a dope comprising an acid and a copolymer consisting essentially of recurring units (I) of the formula [Figure] and recurring units (II) of the formula [Figure] wherein the mole ratio of units I to II is between 20:80 and 95:5, consisting of a. combining and mixing (i) a slur

A process for preparing a dope comprising an acid and a copolymer consisting essentially of recurring units (I) of the formula [Figure] and recurring units (II) of the formula [Figure] wherein the mole ratio of units I to II is between 20:80 and 95:5, consisting of a. combining and mixing (i) a slurry of monomers consisting essentially of one or more dihydrazides in particulate form of the formula [Figure] in one or more diesters in the liquid state of the formula [Figure] wherein the mole ratio of dihydrazide to diester is between about 1:1 and about 2:1, and (ii) an acid selected from the group consisting of oleum, chlorosulfonic acid, polyphosphoric acid, and mixtures thereof, whereby a monomer solution is formed, and then b. maintaining said monomer solution for a period of time at a temperature sufficient to polymerize said monomers, thereby obtaining a dope comprising said fiber-forming copolymer in said acid, wherein Ar represents a divalent aromatic radical, R represents a C1 to C4 alkyl, and -X represents an anion present in said acid.