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Novel photoluminescent donor–acceptor poly(p-phenylenevinylene)-type conjugated polymers containing thiophene and 1,3,4-thiadiazole units in the main chain were synthesized from 2,5-bis(5-bromomethyl-2-thienyl)-1,3,4-thiadiazole and 1,3/1,4-benzenedialdehyde by Wittig–Horner reaction. The synthesized polymers were characterized by the use of thermal analysis and spectroscopic (infrared, UV-visible absorption, and photoluminescence) measurement. The resultant material exhibited bluish green, green, and orange fluorescence in their solution and thin film and solid forms, respectively. The redox property of the polymers has also been studied by cyclic voltammetry. The optical and electrochemical studies reveal that these novel polymers are new promising materials for the development of efficient polymer light-emitting diodes. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Novel dibenzylpiperidinium salts with nonnucleophilic anions (DBPi-SbF6, DBPi-PF6) have been prepared as latent cationic initiators. Utility of these salts in the photo and thermal-induced cationic polymerizations of epoxide and vinyl ether monomer systems has been studied. The new initiator, DBPi-SbF6 showed good solubility, high reactivity, and high thermal latency for polymerizations of epoxide and vinyl ether monomers with only 1 wt % of concentration. Cationic polymerization of vinyl ether monomer was significantly faster than epoxide monomer by the synthesized initiators. This article describes the synthesis, characterization, and activity of novel initiators. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Novel Sulfonium salts with non-nucleophilic anions were synthesized and applicability of these salts as initiators was demonstrated by carried out polymerization (photo and thermal) of epoxides as well as vinyl ether monomers. Newly synthesized initiators showed good activity for the photo and thermal polymerization. Synthesis, characterization, and activity of initiators have been described. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008.

Atom transfer radical polymerization (ATRP) was used to prepare poly(acetoxystyrene) (PAS) with a controlled molecular weight and narrow polydispersity. Using 1-phenylethylbromide (PEBr)/CuBr/Cu(0)/2,2′-bipyridine as an initiating system, the heterogeneous ATRP of 4-acetoxystyrene was carried out to form PAS as a precursor polymer. The reaction follows the first-order kinetics with respect to the conversion of monomer. A linear molecular weight (polydispersities Mw/Mn = 1.07–1.27) indicates the “living”/controlled nature of polymerization. The obtained PAS was chemically modified to obtain succinylated poly(hydroxystyrene) (Succ-PHS). The formulation of Succ-PHS, crosslinker (benzoguanamine-formaldehyde), and triphenylsulfonium triflate (TPST) as a photo acid generator (PAG) was carried out by UV irradiation using an i-line tool. The performance of the resultant polymer as the negative resist pattern photoresist for photolithography was studied with instrumental techniques. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3560–3566, 2007

Novel 1-methoxycarbonylethylmethylphenylsulfonium salts with nonnucleophilic anions, namely, hexafluorophosphate, hexafluoroantimonate, and tetrafluoroborate, were synthesized by the reaction of 1-methoxycarbonylethylphenylsulfide and dimethyl sulfate followed by anion exchange with potassium hexafluorophosphate, sodium hexafluoroantimonate, and sodium tetrafluoroborate, respectively. The cationic polymerization (photopolymerization and thermal polymerization) of epoxy and vinyl ether monomers was carried out to demonstrate the applicability of the newly synthesized sulfonium salts. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3157–3163, 2007

Two diamine monomers, 4-[4-(1-methyl-1-phenylethyl)phenoxy]-1,3-diamino benzene and 4-{4-[(4-methylphenyl)sulfonyl]phenoxy}-1,3-diamino benzene, were synthesized, and both diamines were polycondensed with three commercial dianhydrides to obtain aromatic polyimides containing pendant groups. The polyimides were characterized by solubility tests, viscosity measurements, IR, 1H-NMR, and 13C-NMR spectroscopy, X-ray diffraction studies, and thermogravimetric analysis. The polyimides had inherent viscosities of 0.33–0.58 dL/g in m-cresol at 30 ± 0.1°C. All the polyimides were amorphous and were soluble in solvents such as N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N,N-dimethylformamide, and m-cresol. Thermogravimetric analysis of the polyimides indicated no weight loss below 410°C under a nitrogen atmosphere. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1377–1384, 2005