Abstract: The development of defect-free composite membrane (CM) is often challenging due to poor dispersion and distribution of filler particles in the polymer matrix. Despite the attractive physicochemical properties and gas separation performance of carbon nanotube (CNT) based CM, CNT displayed poor dispersion characteristics in most polymer matrix domain. Instead of incorporating CNT, a viable alternative, carbon nanofiber (CNF) which exhibits similar properties as CNT, but improved dispersion quality in the polymer matrix is found. In this work, CNF particles were incorporated in poly(2,6-dimethyl-1,4-phenylene oxide) (PPO_dm) polymer continuous phase for CM development. The optimum gas separation performance of the PPO_dm-CNF CM (11.25 at 197.02 barrer of CO₂ permeability) was obtained at 3 wt% of CNF loading. Compared to pristine PPO_dm membrane, CO₂ permeability and CO₂/CH₄ selectivity of PPO_dm-3 wt% CNF CM were enhanced by 180% and 55%, respectively. At 3 wt% CNF loading, the filler particles were dispersed and distributed more homogenously, in which no obvious CNF agglomeration was observed. In addition, the incorporation of CNF particles also enhanced the mechanical and thermal properties of the resultant CM.

Key words: Carbon nanofiber, Composite membrane, Carbon dioxide, Gas separation

摘要： The development of defect-free composite membrane (CM) is often challenging due to poor dispersion and distribution of filler particles in the polymer matrix. Despite the attractive physicochemical properties and gas separation performance of carbon nanotube (CNT) based CM, CNT displayed poor dispersion characteristics in most polymer matrix domain. Instead of incorporating CNT, a viable alternative, carbon nanofiber (CNF) which exhibits similar properties as CNT, but improved dispersion quality in the polymer matrix is found. In this work, CNF particles were incorporated in poly(2,6-dimethyl-1,4-phenylene oxide) (PPO_dm) polymer continuous phase for CM development. The optimum gas separation performance of the PPO_dm-CNF CM (11.25 at 197.02 barrer of CO₂ permeability) was obtained at 3 wt% of CNF loading. Compared to pristine PPO_dm membrane, CO₂ permeability and CO₂/CH₄ selectivity of PPO_dm-3 wt% CNF CM were enhanced by 180% and 55%, respectively. At 3 wt% CNF loading, the filler particles were dispersed and distributed more homogenously, in which no obvious CNF agglomeration was observed. In addition, the incorporation of CNF particles also enhanced the mechanical and thermal properties of the resultant CM.

关键词: Carbon nanofiber, Composite membrane, Carbon dioxide, Gas separation