abstract |
A method of making polyetherimide comprising reacting a first diamine having four bonds between the amine groups, a second diamine having greater than or equal to five bonds between the amine groups, 4-halophthalic anhydride and 3-halophthalic in the presence of a solvent and a polymer additive to produce a mixture comprising 3,3'-bis(halophthalimide)s, 3,4'-bis(halophthalimide)s, 4,4'-bis(halophthalimide)s, solvent and the polymer additive wherein the molar ratio of 3-halophthalic anhydride to 4-halophthalic anhydride is 98:02 to 50:50 and the molar ratio of the first diamine to the second diamine is 98:02 to 02:98; and reacting the mixture with an alkali metal salt of a dihydroxy aromatic compound to produce a polyetherimide having a cyclics content less than or equal to 5 weight percent, based on the total weight of the polyetherimide, wherein the polymer additive dissolves in the solvent at the imidization reaction temperature and pressure. |