| 摘要 |
<p>1,209,207. Polyhydrazides. GLANZSTOFF A.G. 8 May, 1968 [10 May, 1967],No. 21776/68. Heading C3R. A novel composition comprises a solution of a polyhydrazide containing units of formula where R is naphthylene or phenylene and R<SP>1</SP> is phenylene or a diphenyl ether group, in aqueous alkali metal hydroxide solution. The polyhydrazide may be dissolved in the alkali metal hydroxide solution, e.g. a solution of sodium or potassium hydroxide, the solution shaped, e.g. by spinning fibres or casting films, and the polyhydrazide precipitated. e.g. by dilution or acidification: the material may then be heated to convert it to insoluble and infusible polyoxadiazole polymer.</p> |
