Multistage drawing scCO2-assisted ultrahigh molecular weight polyethylene/activated nanocarbon fibers and their performance.

Extremely large specific surface area (~ 2400 m2/g) of modified activated nanocarbon (MANC) particles were prepared from bamboo activated carbon particles. The UHMWPE/MANC fibers gelated with scCO2-assistance were drawn to a remarkably large achievable draw ratio, orientation factor and ultimate tensile tenacity by applying a 5-stage drawing technique. The ultimate tensile tenacity acquired for 5-stage drawn scCO2UHMWPE/MANC fiber approached 164 g/d, which is ~ 370%, ~ 60% and ~ 30% higher than those of the proper one-stage drawn UHMWPE, UHMWPE/MANC and scCO2UHMWPE/MANC fibers, respectively. Considerably reduced dynamic transition temperature and lamellar thickness values were evaluated for the scCO2UHMWPE/MANC fibers compared with the equivalent UHMWPE and UHMWPE/MANC as-spun fibers gelated in nitrogen atmosphere, respectively. Probable reasons accounting for these considerably improved ultimate tensile tenacities of 5-stage drawn scCO2UHMWPE/MANC fibers and lower dynamic transition temperatures of their as-spun fibers are proposed. [ABSTRACT FROM AUTHOR]