A volume-adjustable cavity of molding machine for polymer foaming was fabricated with renovation of an ordinary injection molding machine. Polypropylene (PP) composite foams were prepared by chemical foaming method ...A volume-adjustable cavity of molding machine for polymer foaming was fabricated with renovation of an ordinary injection molding machine. Polypropylene (PP) composite foams were prepared by chemical foaming method via the volume-adjustable cavity of the molding machine. The decompressing and short shot processes in preparing the samples were carded out to adjust the cell structure of the foamed samples. The structures that foamed insufficiently, moder- ately, and excessively were observed in these two foaming processes. The foamed PP composite samples generated in decompressing pro- cess have more desirable cell s^cture than those generated by short shot process, specifically, the cell structure with the cell size of 46.97 IJxn, cell density of 3.18x 106 cell/cm3, and cell size dispersion of 10.76 ~m was achieved in the decompressing process. A controlled foaming process was realized through the decompressing process using the injection foaming equipment with a volume-adjustable cavity. The foamed PP composite has the insufficient, moderate, and excessive foamed structures in these two foaming processes.展开更多
基金Supported by the National Natural Science Foundation of China(21264004)the Guizhou Province Inorganic Nonmetallic Key Laboratory of Functional Materials(2012-004)the Industry Revitalization Plan Project of Guiyang City(2012101-3-9)
文摘A volume-adjustable cavity of molding machine for polymer foaming was fabricated with renovation of an ordinary injection molding machine. Polypropylene (PP) composite foams were prepared by chemical foaming method via the volume-adjustable cavity of the molding machine. The decompressing and short shot processes in preparing the samples were carded out to adjust the cell structure of the foamed samples. The structures that foamed insufficiently, moder- ately, and excessively were observed in these two foaming processes. The foamed PP composite samples generated in decompressing pro- cess have more desirable cell s^cture than those generated by short shot process, specifically, the cell structure with the cell size of 46.97 IJxn, cell density of 3.18x 106 cell/cm3, and cell size dispersion of 10.76 ~m was achieved in the decompressing process. A controlled foaming process was realized through the decompressing process using the injection foaming equipment with a volume-adjustable cavity. The foamed PP composite has the insufficient, moderate, and excessive foamed structures in these two foaming processes.