Siloxane-based segmented poly(urethane-urea) elastomer: Synthesis and characterization

摘要

A series of segmented poly(urethane-urea) block copolymers were synthesized with varying proportions of polydimethylsiloxane diols in combination with polytetramethylene ether glycol (PTMG) using 4,4'-methylenediphenyl diisocyanate followed by chain extension with a (50:50 mol %) mixture of 4,4'-methylene-bis(3-chloro-2,6-diethylaniline) (M-CDEA) and 1,4-butanediol (BD). The molecular structures of polydimethylsiloxane urethane-ureas were characterized by ATR-FTIR and ~1H-NMR spectroscopic techniques. Distribution of siloxane domain and its influence on surface roughness were investigated by scanning electron microscopy (SEM) and atomic forced microscopy (AFM), respectively. The mechanical and thermal properties of the elastomers were studied by thermogravimetric analysis, dynamical mechanical thermal analysis, and tensile measurement. The results showed that by incorporation of polydimethylsiloxane diol and M-CDEA chain extender in polyurethane formulation, some improvements in thermal stability, fire resistance and surface hydrophilicity were achieved.