본 논문에서는 SBS-g-POEM 블록-그래프트 공중합체, 이온성 액체(EMIMTFSI) 및 ZIF-8 나노 입자를 사용하여 CO2/N2 기체를 분리하기 위한 혼합 매질 분리막(MMMs)을 개발하였다. SBS-g-POEM은 낮은 비용이 드는 자유 라디칼 중합 법을 통해 합성된 유연한 블록-그래프트 공중합체이다. EMIMTFSI는 SBS-g-POEM 매트릭스에 용해시켰으며, 합성된 ZIF-8 나노 입자들 역시 공중합체의 매트릭스에 분산시켰다. 제조된 시료들의 특성은 푸리에 변환 적외 분광법(FT-IR), 시차 주사 열량계(DSC), 주사 전자 현미경(SEM), X선 회절 분석(XRD)을 통해 확인하였으며, 분석 결과 각 성분들은 서로 간의 좋은 혼화성을 나타내었다. 기체 분리 성능은 time-lag measurements를 통해 확인되었으며, 537.0 barrer의 CO2 투과도와 15.2의 CO2/N2 선택도를 나타내었다. 이를 통해 첨가된 EMIMTFSI와 ZIF-8 나노 입자는 CO2/N2 선택도를 크게 희생시키지 않고 기체 투과 도를 두 배 이상 향상시키는 것으로 확인되었다.

An organic filler, bis-(N-α-amido-3,4-dihydroxyphenylalanine)-1,7-heptane dicarboxylate (DOPA-C7) is applied to gas separation membranes for CO2/N2 separation. The weak interaction between SBS and DOPA-C7 improves CO2/N2 selectivity, from 14.1 to 21.1 with increasing of CO2 permeability from 347.5 to 349.7 Barrer. This phenomenon is caused by the catechol group of DOPA-C7 that can work as a Lewis Base. However, the strongly interacting PEBAX/DOPA-C7 membranes show a typical trade-off behavior, a decrease in CO2 permeability and increase in CO2/N2 selectivity with the filler contents. This results demonstrate that interactions between the filler and polymeric matrix can cause negative effects on the gas separation performance. This work opens up the feasibility of using a catecholic compound in gas separation membranes.

For facilitated olefin/paraffin separation, poly(ethylene-alt-maleic anhydride)-g-O-(2-aminopropyl)-O′-(2-methoxyethyl) polypropylene glycol (PEMA-g-PPG) is reported by facile, cheap and moderate-condition synthesis. PEMA-g-PPG provided effective polymer matrix for partially polarized silver nanoparticles (AgNPs) and 7,7,8,8-tetracyanoquinodimethane (TCNQ). AgNPs could facilitate olefin transport through π-complexation, while TCNQ activated surface of AgNPs for partial polarization as a strong electron acceptor. The FT-IR and TEM image supported improved interactions between PEMA-g-PPG and AgNPs. The best separation performance was obtained with 1:3 wt ratio of PEMA-g-PPG:AgNPs, showing 7.8 GPU for mixed gas permeance and 17.5 selectivity for propylene/propane.