Preparation of The TPU Micro foaming Matrix by Using supercritical Carbon Dioxide

• Main Authors: YANG.HSI-CHING, 楊鍚卿
• Other Authors: 許瑞祺
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/82309094688921174275

碩士 === 長庚大學 === 化工與材料工程研究所 === 95 === Abstract The study is using supercritical carbon dioxide to prepare TPU（Thermoplastic polyurethane）foaming matrix and optimum foaming condition , the experiment studies the effect on the TPU foaming matrix which effect by the operation conditions such as temperature、pressure and soaking time. Furthermore, the change in degree of Tg before and after foamed、Young’s modulus and tensile strength are being probed. Form the experimental results, using supercritical carbon dioxide as the foaming agent, the temperature of making TPU foaming matrix will be controlled above 40℃. The situation of foaming is more obvious when the temperature is higher. Under the better foaming temperature of 60℃, operating at higher pressure, when soaking time increases, foaming density and cell density of matrix will be heavier, and its hole degree, volume expansion rate and cell size will be smaller. Under the same operating temperature and pressure , when the soaking time increases, the foaming density of matrix and the cell size will become smaller, and its hole degree, volume expansion rate and cell density will be larger. As present, the minimum cell size of foaming matrix is 11.85μm, and the biggest cell density about 1012cell/cm3. Achieve the micro foaming matrix（20μm-70μm）on the industry. However, Young’s modulus and tensile strength will decrease as well.