Properties of Poly(ether-b-amide)/MMT Composites Prepared with in-situ Polymerized PA12/MMT Nanocomposites

PA12/montmorillonite nanocomposites (M-PA), polyamidel2 (PA12) oligomers intercalated into the crystalline layers of MMT, were synthesized by in-situ polymerization with 4,4'-methylene bis(cyclohexyl amine), 12-aminododecanoic acid, and MMT. Poly(ether-b-amide) (PEBA)/MMT nanocomposites (C-PEBA) consisting of crystalline hard segment and amorphous soft segment from M-PA block and PTMG block repectively were prepared with M-PA and isocyanate terminated poly(tetramethylene glycol) prepolymer by hexamethylene diisocyanate (HDI). As a result, the crystalline melting enthalpy increased up to 5 wt% and then decreased with increasing the MMT content. The maximum strain and strength of the C-PEBA were shown at 3 wt% of MMT content and the values were larger than those of the control PEBA (B-PEBA), simply MMT blended one. However, the permanent setting of C-PEBA decreased with increasing the MMT content, especially at more than 5 wt%, similar to or less than those of Pebax (R) commercialized PEBA and a typical polyurethane thermoplastic elastomer (TPU).