Homogenous wettability modification of cohesive polyethylene powders in a plasma-enhanced spouted bed enriched by adding coarser particles and vibration

Abstract

Surface modification of C group powders is complex due to its strong inter-particle forces. In this paper, a plasma-enhanced spouted bed was proposed to ameliorate the hydrophilicity of 3 µm polyethylene powders. The effect of fluidization optimization on wettability modification was primarily investigated by introducing mechanical vibration and coarser aeratable particles. As a results, complete fluidization of all particles was obtained when the spouted bed was agitated. The method of combined vibration and adding 80 µm particles achieved the lowest fluidization gas velocity. Moreover, optimal hydrophilicity and uniformity was achieved, suggesting more intensive gas–solid mixing between plasma and powder surfaces leading to a better modification. SEM and FT-IR results show carbonyl and carboxyl groups were incorporated on powder surfaces without affecting their bulk morphology. This study gives novel insights into the fluidization quality for wettability modification and vital findings necessary to promote the application of plasma-enhanced spouted bed for industrial powder processing.