Structural characterization and mass transfer properties of nonporous segmented polyurethane membrane: Influence of hydrophilic and carboxylic group

摘要: Abstract An attempt has been made to investigate the influence of hydrophilic and carboxylic groups on structure mass transfer properties polypropylene glycol (number average molecular weight 1000 g mol −1 , PPG 1000) based segmented polyurethane (SPU). Polyethylene 3400 g mol PEG 3400) (hydrophilic segment) or dimethylol propionic acid (DMPA) (carboxylic group) combination 3400 DMPA were used modify SPU. For comparison, SPU without hydrophilic/carboxylic group was also synthesized. Structures investigated by Fourier-transform infrared (FT-IR), wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) tensile tester. Mass equilibrium sorption water vapor permeability measurements. FT-IR spectra C O stretching indicated that with introduction in polymer backbone, hydrogen bonding urethane became weaker stronger respectively. Nearly amorphous structures all samples evidenced WAXD DSC results. The presence increases interaction between chains, which glass transition temperature ( T g ) make tough. In contrast flexible segment decreases percent strain at maximum load. Experimental results revealed not only influenced region but chains. Presence enhances as well (WVP). Abrupt changes observed for due more polar longer chains will originates holes membranes. membrane content, lowest permeabilities characterized a higher degree physical cross-linking imposed functionality.