| 摘要 |
PURPOSE:To obtain the titled diaphragm rich in heat resistance, by using a composition consisting of polybutylene terephthalate and polytetramethylene ether glycol as the base material of the diaphragm for a filter press. CONSTITUTION:The composition of the diaphragm for a filter press consists of 20-80wt% of polybutylene terephthalate (hereinafter, referred to as 'PBTP') and polytetramethylene ether glycol (hereinafter, referred to as 'PTMEG') with a number average MW of 800-3,000. The %-ratio of PBTP and PTMEG is 20-80:80-20 and, if the ratio of PTMEG is 20% or less, the rigidity of the diaphragm becomes too high and, if 80% or more, the solvent resistance thereof becomes inferior. If the number average MW of PTMEG is 800 or less, the diaphragm is inferior in heat resistance and, if 3,000 ore more, said diaphragm is interior in processability. |
