Long carbon chain polyamide based thermoplastic elastomer (LCPAE) represents a category of high-performance thermoplastic elastomer, consisting of long carbon chain polyamide (LCPA) as hard segments (HS) and polyether as soft segments (SS) [1].Commercial LCPAE, as Pebax and Vestamide E, covers the Shore hardness from 25D to 70D, with tunable properties for an extended range of application fields[2, 3]. A series of Novel PA1012-based LCPAEwere synthesized by polycondensation of carboxyl-terminated PA1012 HS with PTMEG（polytetramethylene ether glycol）SS. A family of high-performance LCPAE materials was obtained by adjusting the molecular weight of HS, SS and their relative ratio(Fig1). LCPAE1, 2 were typical thermoplastic elastomers, while LCPAE3, 4, 5were plastics according to their engineering strain-stress behaviors.Based on the In-situ infrared dichroism and in-situ WAXD/SAXS measurements, the microstructural evolution during uniaxial deformation was probed, and the structure-properties relationship was established in this work. We acknowledge generous financial support by following grants: National Natural Sciences Foundation of China (21574140). References: [1]Jiri George Drobny. Handbook of Thermoplastic Elastomers, 1st ed.Newyork: William Andrew Publishing; 2007. [2]Jignesh P. Sheth, Jiannong Xu, Garth L. Wilkes. Polymer, 2003, 44, 743-756. [3]Subiman Ghosh, D.Khastgir, Anil K. Bhowmick. Polymer, 1998, 39, 3967-3975.