Hyper-cross-linked porous polymers (HCPs) are proposed as sorbents for the removal of aromatic volatile pollutants by using toluene as a representative of the BTX family. The hierarchical (micro and meso) porous architecture of the HCPs has been established by N2 physisorption at 77 K while the toluene adsorption capacities were determined by volumetric adsorption at 308 K. The HCPs display very high toluene uptakes, reaching adsorption capacities as high as 154% in weight for the polymer obtained with a tetraphenyl­methane (TPM) and a formaldehyde dimethyl acetal (FDA) ratio of 1/16, whereas only very low uptakes were observed for aliphatic molecules such as n-hexane. HCP materials experience swelling effects evaluated by comparing the volume assessed via N2 physisorption with the volume occupied by toluene molecules in volumetric adsorption experiments. A multispectroscopic approach involving FT-IR and solid-state NMR techniques gave direct proof of the close spatial proximity between the polymeric host framework and guest BTX molecules. Solid-state 1H and 13C NMR spectroscopies have unambiguously identified the presence of CH/π interactions between the guest molecules and the porous framework of the hyper-cross-linked polymers.

Mixed-matrix membranes (MMMs) are membranes that are composed of polymers embedded with inorganic particles. By combining the polymers with the inorganic fillers, improvements can be made to the permeability compared to the pure polymer membranes due to new pathways for gas transport. However, the fillers, such as hyper cross-linked polymers (HCP), can also help to reduce the physical aging of the MMMs composed of a glassy polymer matrix. Here we report the synthesis of two novel HCP fillers, based on the Friedel–Crafts reaction between a tetraphenyl methane monomer and a bromomethyl benzene monomer. According to the temperature and the solvent used during the reaction (dichloromethane (DCM) or dichloroethane (DCE)), two different particle sizes have been obtained, 498 nm with DCM and 120 nm with DCE. The change in the reaction process also induces a change in the surface area and pore volumes. Several MMMs have been developed with PIM-1 as matrix and HCPs as fillers at 3% and 10wt % loading. Their permeation performances have been studied over the course of two years in order to explore physical aging effects over time. Without filler, PIM-1 exhibits the classical aging behavior of polymers of intrinsic microporosity, namely, a progressive decline in gas permeation, up to 90% for CO2 permeability. On the contrary, with HCPs, the physical aging at longer terms in PIM-1 is moderated with a decrease of 60% for CO2 permeability. 13C spin-lattice relaxation times (T1) indicates that this slowdown is related to the interactions between HCPs and PIM-1.

Polymers of Intrinsic Microporosity represent one of the most promising polymeric materials for gas separation applications. Their very rigid and contorted backbone induces unusually high free volumes and high internal surface area, with high gas permeabilities and moderate ideal selectivity, especially for O2/N2, CO2/N2 pairs with values lying above the Robeson's upper bound. However, the high FFV of PIM1 tends to be shortlived, soon collapsing to leave fewer the fillers and the polymeric matrix in addition to aging effects have been also monitored through ss-NMR spectroscopy. The 13 C spin-lattice relaxation time (T1) measurements reveal that PIM1 chains intercalation between T-O-T lamellar sheets could be one of the mechanisms responsible of PIM1 slowing down aging. Chains confinement between lamellar sheets could play a significant role in reducing chains densification, while maintaining small free volumes.

An optimized Friedel -Crafts based methodology to prepare high surface area and pore volume hypercrosslinked polymers (HCPs) is here presented. A significant reduction in catalyst quantities resulted in an HCP showing SSABET of 905 m 2 /g and total pore volume of ≈ 1.12 cc/g. Spectroscopic investigations (DR-FTIR and SS-NMR) reveal that lowering the amount of catalyst avoid uncontrolled reaction pathways. For the optimized material CO2 uptakes are 2.55 mmol/g at 273 K and 1 bar. High pressure measurements at 298 K resulted in the uptake of 7.33 mmol/g of CO2 at 24 bar and 3.84 mmol/g of CH4 at 42 bar.

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