Novel Soluble Propargylether-Terminated Ester-Imide Prepolymers: I. Their Syntheses and Characteristics:

Novel ester-imide prepolymers terminated by 3-(4-aminophenoxy)-propane-1-yne (4-APE) as a thermally curable group were successfully synthesized. The practical preparation route for 4-APE via tosylate (2) is newly developed. Prepolymers were prepared from bisphenol-A bis(trimellitate)dianhydride (ESDA) having an ester moiety of dianhydride, aromatic diamine, and 4-APE. The properties of the cured resins of the prepolymers were evaluated and showed excellent mechanical and thermal properties, i.e. flexural strength of 269–370 MPa and Tg’s of 225–269 °C. Moisture absorption of 0.20–0.78%, and dielectric constants of 3.0–3.2 were also measured.