Jt. Gu et Cs. Wang, THE INTERFACIAL POLYCONDENSATION OF TETRABROMOBISPHENOL-A POLYCARBONATE .2. REACTIVITIES AND PHASE DISTRIBUTION OF CATALYSTS, Journal of applied polymer science, 50(1), 1993, pp. 149-157
Tetrabromobisphenol-A (TBBPA), a sterically hindered bisphenol, is kno
wn to give only low molecular weight polymers using the interfacial pr
ocess. The low reactivity is attributed to the bulkiness and electron-
withdrawing bromine substituents at the ortho positions. The optimum r
eaction conditions for the interfacial polymerization of TBBPA using p
yridine derivatives as a catalyst have been developed. From the two-ph
ase concentration distribution constant (K(e)) and pK's values of trie
thylamine, 4-dimethylaminopyridine (DMAP), and TBBPA, the critical pro
cess parameters were obtained. Because of its high nucleophilicity and
facile leaving character, the DMAP catalyst system produces a high mo
lecular weight TBBPA-polycarbonate (PC) successfully. The profile of t
he process was followed to obtain a better understanding of the reacti
on mechanism. (C) 1993 John Wiley & Sons, Inc.