ISSN:
1022-1352
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Two types of new polyurethanes with a highly NLO active chromophore, 2-[4-[4-[bis(2-hydroxyethyl)amino]phenylazo]benzylidene]malonitrile (HAPM), in the polymer side chain were synthesized (PU1-DCN and PU2-DCN) and characterized. The diisocyanate components of the polymers are 2,4-tolylene diisocyanate and 3,3′-dimethoxybiphenyl-4,4′-ylene diisocyanate. The molecular weights of PU1-DCN and PU2-DCN were determined to be M̄w = 23000 (M̄w/M̄n = 2.19) and M̄w = 22000 (M̄w/M̄n = 2.34), respectively. The final products are readily soluble in polar aprotic organic solvents, like tetrahydrofuran, N,N-dimethylformamide, cyclohexanone, etc. Good optical quality films were obtained by spin coating. The glass transition temperatures of both polymers were found to be 158-159°C. They showed no melting points in the DSC curves, suggesting an amorphous phase. It was found that the electro-optic coefficient of PU1-DCN was r33 = 62.7 pm · V-1 at 633 nm wavelength. The macroscopic second-order hyperpolarizability at 1064 nm wavelength was determined to be χ(2) = 136 pm · V-1 for PU1-DCN and χ(2) = 120 pm · V-1 for PU2-DCN.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
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