접합형 이성분 용융고분자물 유동의 Die 출구에서의 휨 현상에 대한 이론적 해석

Theoretical Analysis of the Exit Bending Phenomenon in Bicompanent Polymer Melt Flow

A bending phenomenon at the die exit was theoretically analyzed in the case of stratified bicomponent polymer melt flow through a slit die. A bending angle $\theta$ is theoretically predicted by solving the dynamic equation of two phases and assuming that the melt viscosity differences of two phases mainly contribute to the bending phenomenon. The equation of predicting theoretical bending angles is given as: $\theta$=$\theta$P-$\theta$P*/$\theta$D* $\theta$D where, $\theta$P=tan-1(2Ddif/H) $\theta$P*=tan-1(2D*dif/H) $\theta$D=$\theta$*D=[tan-1(L/[H-Δ])-tan-1(L/Δ)]/2 The exit bending angles were also determined as functions of melt viscosity differences, phase portions and die dimensions for a Newtonian and a power law fluids.