Process for producing wet spun or shaped structures
US3992504A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 23, 1975 |
| Grant date | Nov 16, 1976 |
| Priority date | — |
| Expiry date | Jul 23, 1995 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD01F6/74
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Fibers and yarn and a process for preparing them comprising dissolving in concentrated sulfuric acid a polymer containing at least 75 mol percent of an aromatic poly-(1,3,4-oxadiazole) having the repeating structural formul a ##SPC1## In which Ar is ##SPC2## the benzene rings in A or B being substituted or unsubstituted; the linking bonds in A being situated m- or p- with respect to each other, and in B situated m- or p- with respect to X; X being --SO.sub.2 -- or --CO--; and n being 1 or 2. The solution is then spun through a spinneret into a substantially water-free precipitating medium of at least one liquid having the formula (II) ##EQU1## IN WHICH R.sub.1, R.sub.2 and R.sub.3 may be the same or different and are alkyl groups having 1 to 4 carbon atoms, and R.sub.3 may also be H, and in which R.sub.1 and R.sub.2 or R.sub.1 and R.sub.3 may together comprise a divalent alkylene radical, the total number of carbon atoms in R.sub.1, R.sub.2 and R.sub.3 being not more than 8, and in which Z is ##EQU2## a being equal to 1 or 2, b being equal to the valence of Z.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.