Effect of polyol structure and molecular weight on the thermal stability of segmented poly(urethaneureas)

摘要: The thermal stabilities of two series segmented poly(urethaneureas) have been correlated with their soft-segment molecular weights and structure. Thermal stability was measured by thermogravimetric analysis (TGA) differential (DTA) in air nitrogen. It shown that polyurethanes based on polytetramethylene glycol (PTMG) are generally more stable for both nitrogen than polyethene (PEG) polypropylene (PPG). In contrast, the lower PPG-based may be attributed to extent interurethane hydrogen bonding arising from incomplete phase separation between soft hard segments an inferior mutual stabilization effect this polyurethane. TGA curves also revealed higher increase PTMG or PEG. is suggested crystallization kinds enhances increases degrees samples. a atmosphere, importance decreases due dissociation at elevated temperature. Hence, B show decomposition temperatures segment concentrations these materials.