Park, KH Lim, JT Song, S Lee, YS Lee, CJ Kim, N 2024-01-21T15:33:31Z 2024-01-21T15:33:31Z 2021-09-05 1999-05-15 1381-5148 https://pubs.kist.re.kr/handle/201004/142187 We synthesized two new diol monomers with benzoxazole-based nonlinear optical (NLO) chromophores, one of which has an additional hydroxyl group as a crosslinkable moiety and the other has a nitrothiophene group as an electron withdrawing unit. The diol monomers were polymerized with 4,4'-methylenebis(phenyl isocyanate) to give NLO polyurethanes, respectively. Linear polyurethane with hydroxyl groups could be crosslinked between side chain chromophores themselves after poling using an additional crosslinking agent such as teramethyl-1,3-xylylene diisocyanate. Temporal stability of electro-optic coefficient of a crosslinked polyurethane was improved compared with that of a linear polyurethane. The second harmonic generation coefficient of linear polyurethane with benzoxazole-thiophene chromophores was 94 pm V-1 (1.064 mu m) and nonresonant d(33) value was 17.1 pm V-1 calculated by two-level model equation. (C) 1999 Elsevier Science B.V. All rights reserved. English ELSEVIER SCIENCE BV 2ND-ORDER NONLINEARITY AROMATIC POLYIMIDES THERMAL-STABILITY POLED-POLYMER DESIGN Nonlinear optical polymers with novel benzoxazole chromophores V. Linear and crosslinked polyurethanes using nitrothiophene and nitrophenol as electron acceptors Article 10.1016/S1381-5148(98)00019-4 1 REACTIVE & FUNCTIONAL POLYMERS, v.40, no.2, pp.177 - 184 REACTIVE & FUNCTIONAL POLYMERS 40 2 177 184 scie scopus 000080051200010 2-s2.0-0032663310 Chemistry, Applied Engineering, Chemical Polymer Science Chemistry Engineering Polymer Science Article 2ND-ORDER NONLINEARITY AROMATIC POLYIMIDES THERMAL-STABILITY POLED-POLYMER DESIGN nonlinear optical polyurethanes benzoxazole chromophores crosslinking second harmonic generation