Comparison of gas separation properties of Polyurethane membranes containing two different bulky chain extenders
1Isfahan University of Technology
2University of Twente
In this assay preparation and gas separation evaluation of the bulky groups contained polyurethane membranes were investigated. Two bulky chain extenders based on Cyanuric Chloride/Aniline/Hydrazine and Cyanuric Chloride/Naphthylamine/Hydrazine were synthesized and used to synthesize two types of Polyurethanes containing Polytetramethyleneglycol (PTMG2000) and Isophorone diisocyanate (IPDI) as polyol and Diisocyanate, respectively. The PUs were synthesized by a two-step bulk polymerization method. Based on DSC results less bulky chain extender contained PU (Aniline/Hydrazine based PU) with more chain mobility showed higher permeability and less CO2/N2 and CO2/CH4 selectivities. The permeabilities in both PUs decrease in the order of: P(CO2) > > P(CH4) > P(O2) > P(N2) which means solubility is the dominant mechanism in gas permeation process in PU membranes. Based on FTIR spectra more phase separation was inferred for PU containing less bulky chain extender (Aniline/Hydrazine based PU). The results showed more phase separation in PU is in favor of higher permeability.