An engineering study of the film embossing process

Abstract

A mathematical model of the dynamics and heat transfer of the film embossing process has been developed. The thermal analysis around the preheat roll is determined from an unsteady, two‐dimensional heat conduction equation along with appropriate boundary conditions by neglecting the curvature of the preheat roll and choosing a Lagrangian reference frame. The heat transfer occurring between the preheat roll and the embossing rolls is based on a one‐dimensional analysis, including both convective and radiative effects. The deformation occurring in the nip region is analyzed for two different situations. For the case where the surface features are small in comparison with the film thickness, a modified one‐dimennsional calendering analysis is given, accounting for the irregular geometry of the embossing roll surface. For the case where the polymer does not make complete contact with the surface of the engraved channel, the local deformation is determined by means of a simple one‐dimensional cavity filling model. The required pressure distribution is determined by means of a simple one‐dimensional cavity filling model, The required pressure distribution is determined by means of a conventional calendering analysis. The analysis for the case of a Newtonian and power‐law model is presented in detail. The model yields qualitatively correct results and is computationally simple.

New epoxy composite thermosets with enhanced thermal conductivity and high Tg obtained by cationic homopolymerization

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Experimental analysis of the thermoplastic film embossing process

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Anomalous first normal stress difference behavior of polymer nanocomposites and liquid crystalline polymer composites

“…The interaction between the fiber-like fillers offsets the force attempting to align the fibers with the direction of the flow where substantial resistances to deformation were observed at low shear rates [19]. The stated interactions are overcome due to the orientation of fibers in the direction of flow at higher shear rates; hence, the arrangement of LCPs matrix and fibers is disrupted [20]. For filled LCPs, negative first normal stress differences were observed in the low-shear rate regions.…”