ABSTRACT
ROHIT H. VORA,1’2’3 * P. SANTHANA GOP ALA KRISHNAN,1 S. VEERAMANI1 and SUAT HONG GOH2 1 Institute o f Materials Research and Engineering (IMRE), 3, Research Link, Singapore 117602 2Department o f Chemistry, National University o f Singapore (NUS), 10 Kent Ridge Crescent, S8-03, Science Drive 3, Singapore 117543 3 Department of Materials Science, National University o f Singapore (NUS), 10 Kent Ridge Crescent, S7-03-01, Science Drive 4, Singapore 117543
Abstract-Two series of co-poly(amic acid)s (Co-PAAs) containing various mole percents of ort/zo-Tolidine (o-TDA) and l,3-bis(3-aminopropyl) tetramethyl disiloxane (SiDA) were prepared by reacting with 3,3’,4,4’-biphenyl tetracarboxylic dianhydride (BPDA) or 3,3’,4,4’-benzophenone tetracarboxylic dianhydride (BTDA) in N-methyl-2-pyrrolidone (NMP) solvent at room tempera ture. Subsequently, from these Co-PAAs, we have formulated two series each of the ionic bond type photodefinable co-poly(amic acid)s (Co-PDPAA), i.e. ionic salts, using N,N-diethylamino ethyl methacrylate (DEEM) and N,N-dimethylamino ethyl methacrylate (DMEM) respectively. Storage stability of these solutions at room temperature was monitored for a period of one month by gel permeation chromatography (GPC), potentiometry and viscometry. Bulk viscosity, inherent viscos ity, acid number and molecular weight all decreased drastically as the storage time increased.
