Sintering kinetics of UHMWPE nascent powders by high velocity compaction: Influence of molecular weight

► Welding of UHMWPE powders via HVC is much faster than via conventional sintering. ► Complete chain reptation is not necessary for efficient welding. ► Wool's welding criterion is not fulfilled for Mw > 106 g/mol. ► Efficient welding is obtained after chain diffusion over the stacking long period. ► Co-crystallization of chains through the interface is a major process of welding.