Modeling Research Of Polymer Transformation From Bulk State To Solid In Vane Plastication Conveying

This thesis builds theoretical model of the process of polymer transformation from bulkstate to solid in vane plastication conveying, and carries out experiments to get parametersand testify the model. Propose the concept ofC pwhich means for the coefficient of pressuretransformation in vane plastication conveying unit for the first time, and quantify the effectsof different parameters on. By deeply understanding the whole process, the function ofbulk density between pressure and temperature in polymer transformation from bulk state tosolid is built. In addition, the related parameters in the model function are simulated bycalculating and testified by experiments.Experiments are carried out in self-designed device to study the effects of materialparameters (crystallization, shape), device parameters (eccentricity, outlet, friction coefficient),and process parameters (rotating speed, temperature) on the transformation of polymer frombulk to solid state. The results show that: the bulk density of non-crystalline material has closerelationship with glass transition temperatureTg, which higher means higher bulkdensity can reach; during the initial stage of compression, polymer powder and pellets canalmost reach the same bulk density, but in the final stage, powder can reach higher bulkdensity than pellets; the bigger of eccentricity, the greater change of bulk density (smallerinitial bulk density but higher final bulk density); discharging lately can reach more higherbulk density; the addition of epoxidized soybean oil (ESO) can reduce friction coefficient,which can reach smaller bulk density; in lower rotating speed (<10r/min) range, polymerbulk density change little according to the rise of rotating speed, but in higher rotating speed(>20), the rise of rotating speed will result in lower bulk density; in the rangeexperiments, the higher of processing temperature, the higher of bulk density can reach.By the comparison of theoretic model and experimental data, the proposed model ofpolymer transformation from bulk to solid state in vane plastication conveying is accord withreality, which can guide the optimizing of device and process. In the meantime, the proposedmodel can provide theory and experimental data support for the subsequent computersimulation.