A MATHEMATICAL MODEL FOR THE HEAT SEALING OF LINEAR, SEMI-CRYSTALLINE POLYMERS

摘要

A mathematical model and computer simulation describing the heat sealing process for linear, semi-crystalline polymer films has been developed. Accounting for the effects of conduction heat transfer with phase change, interfacial melting, and polymer chain scaling relationships based upon reptation theory to describe chain diffusion and strength development at the bonding interface during the transient, non-isothermal heat sealing process, the model demonstrates that interfacial melting, wetting, and chain interdiffusion are all important contributions to the development of the seal strength during rapid heat sealing. The model has been used successfully to compute the time dependence of interface strength development during the heat sealing process for linear polyethylene copolymers.