Development of a pressure–volume–temperature measurement method for thermoplastic materials based on compression injection molding

Abstract

The pressure-volume-temperature (pvT) relationship of polymers is vitally important information in designing and manufacturing polymers. Due to the special behavior of polymers, however, it is extremely difficult to accurately measure the data in a way that matches the thermal conditions of injection molding, one of the most widely used processing methods. As neither widely used, commercially available measuring devices, nor special equipment mentioned in the literature can fully satisfy this need, it was decided to build a new device able to determine the pvT relationship during injection molding of the polymer. The new device consists of a special mold that can be used on an injection molding machine and a data collection system connected to it. With the help of this device, pvT data can be measured during processing according to the thermal conditions of injection molding, and also considerably faster, and even in an industrial setting.

A Review of Thermoplastic Resin Transfer Molding: Process Modeling and Simulation

“…Also, both methods are limited by the maximum achievable cooling rate, which is far below the cooling rate during injection molding. Szabo and Kovacs [97,98] developed a measurement procedure, which enables the measurement of the pvT properties of amorphous thermoplastics during injection molding, directly in an injection unit. The method works well for ABS, PS, SAN and PC in the pressure range of 7 to 28 MPa.…”