Surface Roughness and Energy on Slip of Polymer Melts
نویسندگان
چکیده
Effect of surface topology and energy on slip velocity of high-density polyethylenes (HDPEs) was studied using treated and non-treated smooth and patterned slit dies. In order to examine the effect of surface roughness, laser ablation method was utilized to micro/nano-pattern the surface of dies. Moreover, effect of surface energy on slip was investigated by applying fluoroalkyl silane-based coatings on smooth and patterned substrates. It was found that slip velocity is decreased for rough dies, due to high friction and penetration of polymer melt into the cavities of the substrates. In addition, silanization increases the slip velocity of polymers extruding from smooth die, but has negligible effect on patterned dies.
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