Development and Application of Die Swell Data Gathering System Based on Multi-function and All-electric Rheometer

摘要

A real-time die swell data gathering system was developed based on laser diameter gauge in order to measure the die swell of the viscoelastic materials. Software of the system is compiled by C language. Data gathering, date display, data saving and date analysis were realized. Experimental procedures were established, by which the die swell can be acquired. The laser gauge is put 5 cm under the die of self-developed multi-function and all-electric rheometer (MAR) to measure the diameter of the extrudate. The rheological behaviors of the PP/PS blends are tested. The change laws of the melt die swell ratio in the condition of different frequency and amplitude were obtained. Compared with the steady-state extrusion, after introducing vibration force field, the melt die swell ratio decreases obviously. The die swell ratio of the blends decrease in fluctuation state with the increase of the frequency; while decreases gradually with the increase of the amplitude. In addition, with the die length-diameter ratio increases, die swell ratio of the blends decreases gradually.