Hypercrosslinked microporous polymers (HCPs) have attracted great attention due to their high surface areas

mild synthetic conditions

abundant building blocks

low cost and easily attainable catalysts. In recent years

knitting strategy with external cross-linker has become a primary method for the preparation of HCPs as a sort of simple

effective and new synthetic strategy. HCPs with high surface areas and tunable porous structures can be prepared by knitting low functionality aromatic compounds

which further expands the range of monomer

eliminates the hazards of by-products and provides possibility to produce large-scale and low cost HCPs. In this review

we summarized novel and general synthetic strategies for the design and synthesis of HCPs. The morphology control of HCPs and applications including gas storage and capture

catalysis

removal of pollutants

drug delivery

energy storage

chromatographic separation

sensing and carbon precursor were also discussed. Finally

we talk about the problems and challenges in the future as well as predict the further development of knitting strategy.