Process for the expeditious formation of a high strength shaped article of poly(6-oxy-2-naphthoate-4-oxybenzoate)
US4574066A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1984 |
| Grant date | Mar 4, 1986 |
| Priority date | — |
| Expiry date | Feb 27, 2004 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2367/00
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Melt extruded poly(6-oxy-2-naphthoate-4-oxybenzoate) shaped articles of relatively high strength and modulus are produced in a lesser period of time than commonly heretofore required in the prior art. The required polymer is capable of exhibiting an anisotropic melt phase and is formed through the reaction of 6-acetoxy-2-naphthoic acid and 4-acetoxybenzoic acid under a combination of melt polymerization conditions which surprisingly has been found to yield a shaped article following melt extrusion which may be heat strengthened in an unusually brief period of time (i.e. two hours or less). The polymerization is catalyzed by a potassium salt (e.g. potassium acetate), and the polymerization conditions require a relatively highly elevated final polymerization temperature. Substantially all of the acetic acid by-product is removed from the polymerization zone prior to concluding the polymerization under reduced pressure conditions. The process of the present invention through the reduction of the required heat strengthening time accordingly makes possible a substantial productivity increase for a given production facility.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.