Synthesis of Azo Polyurethane-Urea and Investigation of its Thermo-Optic Properties

An azo chromophore molecular S(-)-1,2-bis(4-azophenyl-4-nitro)-ethylenediamine (OABANEDA) was synthesized with 4-nitroaniline and S(-)-1,2-diphenyl ethylenediamine by diazo-coupling reaction. The azo polyurethane-urea (OAAPUU) was obtained from OABANEDA, polyether diol (NJ-210) and isophorone diisocyanate (IPDI). The structure of OAAPUU was characterized by the Fourier transform infrared and UV-visible spectroscopy. The physical and mechanical properties of OAAPUU were investigated. The refractive index (

Synthesis and Thermal-Optic Properties of Azo Polyurethane Containing Chiral Unit

A new chromophore containing azo group, 3,3'-dichloro-4,4'–di-(4-amino-azo-phenyl) -diphenylmethane (CAAPM), was synthesized based on 3,3'-dichloro-4,4'-diamino– diphenylmethane, sodium nitrite and benzenamine via diazo-coupling reaction. Azobenzene polyurethane (PU) containing chiral unit was obtained from CAAPM, chiral reagent L(-)-tartaric acid and isophorone diisocyanate (IPDI). The chemical structures of CAAPM and PU were characterized by FT-IR and UV-Vis spectroscopy. The measurements of refractive index (n) and thermo-optic coefficient (dn/dT) of polyurethane were demonstrated at complex light. The values of n and dn/dT were used to calculate the dielectric constant (ε) and its variation with temperature (dε/dT). The dn/dT is 4.2000～-3.7000×10-4°C-1. The conclusion has a little significance to develop new the digital optical switch (DOS).