Study On Thermodnamics Of Phasebehavior For Homopolymer Blends

Technology of material forming and processing is a new technology, which has developed at full speed in recent years. Alternation-blends of polymer-based material is one of the main research direction in Material Science. In changing the property of polymer, people can achieve high-performance and fineness. This is one of the main methods of developing new materials. But the theoretical research of this technology hasn't been perfect yet. Among them the prominent contradiction is the miscibility of polymer blends of almost the entire polymer. Because homopolymer blends always show micro-phase transition, this extremely influences its structure and performance. In the standpoint in technology, appropriate mixing among different polymers and gain with high polymer material high performance, but in science viewpoint, there are still lots of questions needed to make further study and development in the structure and performance of homopolymer blends. The thermodynamic free energy on mixing and the Spinodal equation in ternary homopolymer blends were obtained by making plausible approximation based on Flory's equation of state theory. Because of the non-linear behavior of the Spinodal equation, a numerical solution approach was used and succeeded in solving the problem. Spinodal of polystyrene (PS)/poly(vinyl methyl ether)(PVME)/poly(2,6-dimethyl-1,4-phenylene oxide)(PPE) were simulated over a wide temperature range and the calculated result was coincidence with that of the literature. Also the influence of the molecular weight of the component on the Spinodal phase behavior was studied.