| 摘要 |
High thermal stabilities are achievable in linear or multidimensional sulfone, solvent resistant oligomers by incorporated oxazole, thiazole, or imidazole linkages into the oligomer backbone. Blended oligomers of crosslinking oligomers and noncrosslinking compatible polymers are also described. The oligomers include residues of fourfunctional compounds of the formula: (or isomers thereof) wherein M = -CO-, -S-, -O-, -SO2- or -(CF3)2C-; and Y = -OH, -SH, or -NH2. In an improved method, the reactants are condensed at or below ambient temperature in the presence of pyridine in a suitable solvent such as N,N'-dimethylacetamide (DMAC). |
