Synthesis and characterization of a novel bisfuran/bismaleimide resin

The synthesis of a novel bisfuran/bismaleimide resin based upon 4,4{dollar}spprime{dollar}-bis(2-furfuryl)phenyl ether (BFPE) and 4,4{dollar}spprime{dollar}-bis(maleimido)diphenylmethane (BMI) is explored. The reactions occurring during the thermal cure the BFPE resin are explored via a model compound study utilizing 2-furfurylbenzene (FB) and N-phenylmaleimide (NPMI). The thermodynamics of the Diels-Alder reaction are reported, along with the charge transfer complex formation and the copolymerization properties. The Diels-Alder reaction occurs readily at room temperature, but easily reverses as low as 40{dollar}spcirc{dollar}C, and returns nearly exclusively to starting materials by 60{dollar}spcirc{dollar}C. The charge transfer complex between FB and NPMI was shown to occur, but not to play a significant role in the copolymerization process. The copolymerization reactivity ratios of FB and NPMI are reported, and show FB to react nearly exclusively with NPMI radicals during the polymerization process.; The polymerization pathways of the resin itself are reported. An initial Diels-Alder reaction between the BFPE and BMI produce a linear polymer with molecular weights in the thousands. The subsequent thermal polymerization is postulated to occur mainly through a reverse Diels-Alder reaction followed by a radical copolymerization. The formation of an aromatic polyimide structure yielding water does not occur to a significant extent.; The mechanical properties of the BFPE/BMI resins and of the graphite fiber composites are reported along with two commercial bismaleimide resins: neat 4,4{dollar}spprime{dollar}-bis (maleimido)diphenylmethane (a generic version of Rhone Poulenc's first generation Kerimide resin) and Ciba Geigy's Matrimide{dollar}sp{lcub}rm TM{rcub}{dollar} 5292. Different stoichiometries of each resin were aged at 260{dollar}spcirc{dollar}C and the weight loss data are reported. In the neat resin form, the BFPE and Matrimide show comparable rates of weight loss, but BFPE resin shows superior high temperature performance, both mechanically and thermal-oxidatively, when formulated into a composite.; A commonly studied commercial polyimide, Kapton H film, was studied via {dollar}sp{lcub}13{rcub}{dollar}C cross polarization/magic angle spinning (CP/MAS) to determine the potential of this technique in characterizing the behavior of absorbed water in insoluble, imide containing polymers. {dollar}sp{lcub}13{rcub}{dollar}C spin lattice relaxation times (T{dollar}sb1{dollar}'s) were measured for dry and moisture absorbed, and D{dollar}sb2{dollar}O films to determine the sites of bound water. {dollar}sp{lcub}13{rcub}{dollar}C rotating frame relaxations and inversion recovery cross polarization (IRCP) measurements were performed to determine the effects of bound water on the motional parameters of the polymer itself.