摘要
以新型聚醚酰亚胺预聚体—聚酰胺酸为前驱体,在空气中进行预氧化处理后经700℃炭化制备出炭膜。采用红外光谱(FTIR)、元素分析(EA)、X射线衍射(XRD)和气体渗透等测试手段对400℃、460℃和480℃温度下所制预氧化膜的化学结构、炭膜的微结构和气体分离性能进行了表征。结果表明:预氧化阶段,聚合物链发生了热分解和氧化交联反应,温度越高,热分解和氧化程度越高。炭化后,预氧化膜的交联结构演变成无定形碳结构。预氧化膜的结构差异导致了炭膜的孔结构的不同,从而对炭膜的气体分离性能产生重要影响,其中经460℃预氧化处理后所制炭膜的O2渗透系数可达8.2×10-13(m3(STP.)cm)/(m2..sPa),O2/N2选择性达14.1。
Polyetherimide derived carbon membranes were prepared by pretreating the precursor in air before carbonization at 700℃. The chemical structure, microstructure and gas separation properties of these membranes pretreated at 400, 460 and 480℃ were characterized by FTIR, elemental analysis, XRD and gas permeation tests. The effects of preoxidization on their microstructure and gas separation properties were investigated. Results show that decomposition and oxidation-induced crosslinking reactions occur during the pretreatment. The higher the preoxidization temperature, the higher the degree of decomposition and the degree of crosslinking. After carbonization, the pretreated membranes have an amorphous structure. The differences in the crosslinked structure generated in the pretreatment leads to differences in the micropore structure of the membranes, which can be used to tune gas separation properties. The permeability of all gases investigated exhibits a maximum with a preoxidization temperature at 460 ℃ for which the O： permeability is 8.2 × 10^-13（ m^3（STP）· cm）/（ m^2·s·Pa） and the O2/N2 selectivity is 14.1.
出处
《新型炭材料》
SCIE
EI
CAS
CSCD
北大核心
2008年第3期264-268,共5页
New Carbon Materials
基金
国家自然科学基金(20276008)~~
关键词
聚醚酰亚胺
预氧化
炭膜
气体分离
Polyetherimide
Preoxidization
Carbon membrane
Gas separation
