Low‐Cost Hypercrosslinked Polymers by Direct Knitting Strategy for Catalytic Applications

Abstract

Direct knitting of nucleophilic arene monomers in the presence of electrophilic cross‐linker, like formaldehyde dimethyl acetal, is proven to be a cost‐effective and versatile method for the synthesis of porous organic polymers. The resulting hypercrosslinked polymers (HCPs) are featured by hierarchical porous structure, high surface area, and pore volume. Coordinating functional groups can be easily installed with this method into the rigid aryl network. Direct knitting to HCPs has therefore been widely used in preparing heterogeneous solid catalysts. Wise selection of monomers with rational design of 3D structure and the synergy between the HCP support and the catalytically active species often lead to high efficiency of tailor‐made catalysts without sophisticated operations. On account of all these excellent properties, enthusiasm of researchers to use HCPs in catalysis is increasing rapidly. This review documents the necessity, feasibility, and the great contributions of using HCPs as invaluable tools for catalysis research, and summarizes state of the art of this chemistry. Similar type catalysts obtained by one‐step Scholl reaction are also included in this review.

Recent Advances in Nanofabrication of the Morphology-Controlled Hypercrosslinked Polymers

“…And these methods endow these polymers with diverse inner porosity and outer morphologies (Figure 1). On this basis, some unique properties are revealed on HCPs, and a wide range of practical and potential applications, such as catalysis [8][9][10], adsorption [11][12][13][14], separation, and energy storage/conversion [15][16][17], are also reported by these researchers [8,[11][12][13][14][15][16][17].…”

Advances in porous organic polymers: syntheses, structures, and diverse applications

“…64 The formation HCPs can be achieved through acid-catalyzed Friedel-Crafts reactions involving a Lewis acid catalyst, a reaction solvent, and arene-based nucleophilic and electrophilic species. 65 To avoid products forming through side reactions during the knitting step, the reactions are performed under Ar and N 2 atmospheres to afford pure HCPs as solid materials. 65 The incorporation of metal species into HCPs can be performed through post-modification-by introducing a metal salt or complex-or by using a metal complex as a co-monomer or monomer during the knitting reaction (Figure 2).…”

“…65 To avoid products forming through side reactions during the knitting step, the reactions are performed under Ar and N 2 atmospheres to afford pure HCPs as solid materials. 65 The incorporation of metal species into HCPs can be performed through post-modification-by introducing a metal salt or complex-or by using a metal complex as a co-monomer or monomer during the knitting reaction (Figure 2). 65 HCP materials have been employed in many applications, including energy storage;…”

Conjugated Porous Polymers: Ground‐Breaking Materials for Solar Energy Conversion

“…On the other hand, POPs are pure organic polymers composed entirely by organic units without the presence of metals in their structure. Within the POP classification several categories can be differentiated; the most relevant until now is the CPP, which includes conjugated microporous polymer (CMPs), [25] covalent organic frameworks (COFs), [26] covalent triazine frameworks (CTFs), [27] hyperbranched crosslinked polymers (HCPs) or knitted polymers, [28] porous aromatic frameworks (PAF) also known as porous polymeric aromatic frameworks (PPAFs), [29] polymers with intrinsic microporosity (PIMs), [30] porous molecular solids (PMSs), and coordination cages (CCs) or porous cages, [31] and also some polymeric carbon nitrides (PCN) [32] (Figure 1).…”