Influence of Hard Segment Content on the Water Vapor Permeability of Segmented Shape Memory Polyurethane Membranes
Segmented shape memory polyurethanes (SMPUs) with various hard segment content were synthesized by two- step polymerization from poly (butylenes adipate) glycol (PBAG) as soft segment, toluene-2, 4- diisocyanate (TDI) and 1, 4-butanediol (BDO) as hard segment. The molecular weight of PBAG used was 2000 and 3000. The SMPUs were characterized using differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD). The DSC results indicated that SMPUs had descending phase transition temperature (soft segment crystal melting point, T <,sm>) with the hard segment content increasing and the molecular weight of PBAG decreasing. The phase separation of SMPU increased with the decrease of hard segment content as Well as with the increase of the molecular weight of soft segment, which proved by the WAXD measurements. Water vapor permeability of PU membranes was investigated as a function of PU hard segment content (HSC) by water vapor permeabililty <,1>ty (WVP) measurements. Temperature-sensitive water vapor permeability of SMPU at the phase transition temperature was observed, which was changed slightly with different SMPU hard segment content.
hard segment content water vapor permeability segmented shape memory polyurethane
HUANG He ZHANG Dan WANG Tianjin MAO Zhiping YU Weidong YAN Haojing
Textile Material and Technology Lab, Donghua University, Shanghai 201620, P. R. China Key Lab of Science and Technology of Eco-extile (Donghua University), Ministry of Education, Shangha Key Lab of Science and Technology of Eco-textile (Donghua University), Ministry of Education, Shangh Textile Material and Technology Lab, Donghua University, Shanghai 201620, P. R. China Textiles and M College of Textile, Donghua University, Shanghai 201620, P. R. China
国际会议
上海
英文
546-548
2007-10-15（万方平台首次上网日期，不代表论文的发表时间）