On-line measurement of the P-V-T properties of polymer melts by a special testing mold

摘要

P-V-T(Pressure-Volume-Temperature) relationships of polymers, which are used by software such as Moldflow or C-Mold to predict shrinkage or warpage behavior in plastic components and applied to set processing conditions to achieve optimum results, become increasingly important in their value in material science. In this study, most of P-V-T testing techniques are described, including conventional techniques, improved experimental techniques at high cooling rates, techniques based on IMM under normal processing conditions and some other techniques utilizing ultrasonic technique. And a new P-V-T on-line testing apparatus was developed in order to measure specific volume at processing conditions. The feasibility of this new testing method is that it can be used to get P-V-T data of polymers in mold directly by a special testing mold based on an injection molding machine under normal processing conditions.