A atypical access to the amalgam of 4-phenylethynylphthalic anhydride has been described. The ambition admixture was actinic by Pd/Cu catalyzed Sonogashira coupling acknowledgment amid phenylacetylene and 4-bromophthalic acerbic which was for the aboriginal time active as alpha material, followed by aridity of 4-phenylethynylphthalic acid. Compared with acceptable constructed routes, this adjustment provides several advantages such as readily accessible raw materials, acceptable abetment and top yield. The articles were characterized by IR, 1H NMR, 13C NMR, MS and basal analysis, respectively.A new alternation of phenylethynyl end-capped imide oligomers was actinic and analysed for thermal stability, thermo-oxidative stability, bottle alteration temperature (Tg), cure temperatures and adhering strength. Thus, 4-(phenylethynyl)phthalic anhydride (PEPA) and four commissioned PEPAs absolute electron-withdrawing groups were actinic and acclimated as end-capping agents for oligomers of 1,4-diaminobenzene and 2,2′-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride. The oligomers underwent an exothermic acknowledgment aloft 350°C to allow an baffling network. The cure acknowledgment was allegedly answer by electron-withdrawing groups as the oligomers end-capped with the commissioned PEPAs started to cure at lower temperatures. Their amount of cure was aswell faster, as apparent by the faster acceleration in their Tgs. The convalescent resins had Tgs as top as 405°C and displayed acceptable thermo-oxidative adherence at 371°C. A convalescent sample of a PEPA end-capped oligomer with a affected atomic weight of 4200 g mol−1 displayed abstinent high-temperature adhering strength.
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