Preparation and characterization of polybutylene succinate foams processed in supercritical carbon dioxide.

초록

Foams have the advantage of low-density, high specific strength and good protection from noise, making them widely applicable to domestic, industrial, and agricultural fields. The most common foam materials are foamed polystyrene (PS), polyurethane (PU), and poly(vinyl chloride) (PVC) etc. but these traditional polymer foams cause serious environmental problems. Therefore, the foaming of Polybutylene succinate(PBS) has become a particularly important project. Because of its environmental friendly nature, However, the PBS has low melt strength that it has been often considered unsuitable for making it into foams. To solve this problem, we have increased the melt strength of PBS using low molecule chemical of Isocyanate. We have conducted the character analysis of modified PBS using the gel content, DSC. The result shows that the highest gel content can be obtained by reacting the sample with the branching agent for about 8 min inside the Brabender Mixer. We have applied the pressure quench method of the supercritical fluid to the modified PBS and prepared foams with a blowing ratio of approximately 40 times larger than unfoamed PBS. The main features of the foams using supercritical fluid are a)it does not use chemical foams and b)it can control a cell structure and blowing ratio by controlling the saturation pressure, saturation temperature and vent rate.