Creating a module that achieves sustainable CO2 capture while being compatible with the existing industry is paramount in overcoming the current CO2-driven environmental issues. This paper presents the fabrication of hollow fiber sorbents (HFSs) and their respective modules to capture CO2 by the rapid thermal swing adsorption process (RTSA). Poly­(amide-imide) (PAI)/microspheric SiO2 composites were fabricated with a so-called “sieve-in-a-cage” microarchitecture which promotes CO2 diffusion. More importantly, a selected amount of 1,2-epoxybutane (EB)-functionalized poly­(ethylenimine) (PEI), denoted as 0.37EB-PEI, was incorporated into our PAI/SiO2 composites forming PAI/SiO2/0.37EB-PEI HFSs which enhanced the thermal stability with a moderate CO2 sorption uptake of 0.88 mmol CO2 g–1. The resulting HFSs were assembled into a module using either stainless steel (SS) or poly­(tetrafluoroethylene) (PTFE), and their respective CO2-capturing performances in the RTSA process were compared. The two modules had a comparable breakthrough CO2 capacity of 0.42 mmol CO2 g–1 for a wet feed mixture of CO2/He/N2 (14 mol/14 mol/72 mol) (RH 100%) and a comparable CO2 desorption efficiency (i.e., 95% desorption within 2 min) under 100% CO2 at 120 °C due to the presence of the 0.37EB-PEI; however, different thermal properties inherent to the modular materials caused the PTFE-based module to outperform the SS-based counterpart in terms of cooling, enabling the execution of an entire RTSA cycle within 8 min. Additionally, the PAI/SiO2/0.37EB-PEI/PTFE module maintained its breakthrough capacity of 0.42 mmol CO2 g–1 over five consecutive RTSA cycles, confirming its good long-term stability as well.

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We investigated, using extensive molecular dynamics simulations, the role of friction on the thermal rupture of a linear alternating copolymer tethered at one end and pulled by a constant tensile force at the other. Rupture has been described as escape from a metastable minimum of effective bond potential. We studied the effect of friction on the average first passage time and the average rate of chain scission. The role of friction on healing/recombination was also studied.

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