单醚二酐型聚醚酰亚胺的透气性能与分子结构之间关系的研究

合成了一系列单醚二酐型聚醚酞亚胺（ＰＥＩ），研究了它们对Ｈ２、ＣＯ２、Ｏ２、Ｎ２和ＣＨ４５种气体的透过性能与分子结构的关系．结果表明，这类聚醚欧亚胺的分子结构对其透气性和透气选择性有很大的影响，聚合物的自由体积和链段活动性是控制透气性和透气选择性的主要因素．二苯醚四酸二酐（ＯＤＰＡ－４．４＇－二Ｊ氨基二苯异丙烷（ＩＰＤＡ）具有很大的自由体积和较小的链段活动性、很大的透气性和较小的透气选择性，ＯＤＰＡ—４，４’－二氨基二苯酮（ＤＡＢＰ）具有很小的自由体积和较小的链段活动性、很小的透气性和较大的透气选择性，ＯＤＰＡ—３，３’－二甲基二苯甲烷二胶（ＤＭＭＤＡ）具有较大的自由体积和较小的链段活动性、很大的透气性和很大的透气选择性．

STRUCTURE/PERMEABIRITY RELATIONSHIPS OF ODPA-BASED POLYETHERIMIDE MEMBRANES

he permeability coefficients of six different ODPA-based polyethermide membranes to H2, CO2, O2, N2, and CH4. have ho measured at 0. 7 MPa and at temperatures from ambient up to 150 ℃. Systematic variations in chemical structure were found to lead to sighficant changes in permeability coeffidents and ideal separation factors of polyetherimide membranes. Among the six polyetherimdes, ODPA-IPDA with the largest free-volume and larger intrasegmental mobility has the highest permeability and the lowest permselectivity, ODPA-DABP with the smallest free-volume and the smallest intrasegmental mobility has the lowest permeability and the lowest permselectivity, ODPA-DMMDA with the larger fine-volume and smaller intrasegmental mobility has higher permeability and higher permselectivity.