A detailed investigation has been carried out of the pre-polymerisation modification of the polymer of intrinsic microporosity PIM-1 by the addition of two methyl (Me) groups to its spirobisindane unit to create a new chemically modified PIM-1 analogue, termed MePIM. Our work explores the effects of this modification on the porosity of PIM-1 and hence on its gas sorption properties. MePIM was successfully synthesised using either low (338 K) or high (423 K) temperature syntheses. It was observed that introduction of methyl groups to the spirobisindane part of PIM-1 generates additional microporous spaces, which significantly increases both surface area and hydrogen storage capacity. The BET surface area (N₂ at 77 K) was increased by ~ 12.5%, resulting in a ~ 25% increase of hydrogen adsorption after modification. MePIM also maintains the advantages of good processability and thermal stability. This work provides new insights on a facile polymer modification that enables enhanced gas sorption properties.

已经对固有微孔性PIM-1的聚合物进行了预聚合改性的详细研究，方法是在螺双双茚满单元中添加两个甲基（Me），以创建新的化学改性的PIM-1类似物，称为MePIM。我们的工作探索了这种改性对PIM-1孔隙率的影响，并因此影响了其对气体的吸附性能。MePIM使用低温（338 K）或高温（423 K）成功合成。观察到，将甲基引入PIM-1的螺双茚满部分中产生了额外的微孔空间，这显着增加了表面积和储氢能力。BET表面积（N ₂在77 K时）增加了〜12.5％，导致改性后氢吸附增加了〜25％。MePIM还具有良好的可加工性和热稳定性的优点。这项工作提供了对易于改性的聚合物的新见解，该聚合物可实现增强的气体吸附性能。