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Chiral and helical polymers and their resin are very attractive components in catalysis and separation chemistry. This manuscript discusses the synthesis and application of achiral and chiral imidazolium based poly(ionic liquids) (PILs). Imidazolium based cross-linked poly(ionic liquids) or polyelectrolytic-resins ( PIL-resin ) were synthesized by RAFT copolymerization of 1-vinyl-3-ethylimdazolium bromide with different cross linkers. In these PIL-resins, the chirality is induced at anionic part by simple anionic metathesis with optically pure amino acids, L & D-proline that gave six chiral PIL-resins. The morphology of PIL-resins was studied by SEM which shows microfibrils, twisted ribbons, and layered structures. The PIL-resins exhibit very good activity towards Diels-Alder reaction (cyclization of isoprene with different dienes), where quantitative conversions were achieved within 30 min at room temperature. Both catalytic activity and the selectivity remain same during first four recycles of the resin. The chiral PIL-resin catalysed heterogeneous asymmetric Baylis Hillman and Michael addition reactions shown better catalytic activities in comparison with chiral homo polymer. [ABSTRACT FROM AUTHOR]

Nanoparticles-encapsulation poly(ionic liquid) hydrogels possessed extraordinary mechanical strength, highly catalytic efficiency, antibacterial, self-adhesive and self-healing, which could serve as reusable catalysts for the sewage disposal industry. [Display omitted] • The hydrogel presented excellent mechanical and catalytic properties. • The hydrogel exhibited super-tough without the addition of other additives and cross-linking agents. • The hydrogel owned satisfactory self-adhesive and self-healing ability. • The hydrogel owned satisfactory antibacterial properties. The design and fabrication of functional hydrogel materials for catalysis environmental pollutants has gained immense interest. However, fabricating a hydrogel with both excellent mechanical and catalytic properties remains a challenge. Herein, we successfully achieved polyacrylamide/dimethylaminoethyl methacrylate bromododecane p(AM/DMLB) hydrogel with poly(ionic liquids) microspheres as toughened point and catalytic sites. Under the dual effect of ionic crosslinking network and hydrophobic association network, p(AM/DMLB)/PILs-MPs hydrogels exhibit excellent mechanical properties, such as the tensile strength (1.38 MPa), elongation (2000%), and toughness (1.15 MJ∙m−3). Simultaneously, the hydrogel could act as a template for loading of Pd nanoparticles without the addition of other additives and crosslinking agents. The metal-loaded composite hydrogels exhibits excellent catalytic property in the reduction of 4-nitrophenol (4-NP) reaction, and reduction rate constants (K app) was 0.226 min−1. The strategy offers a novel economically feasible route to catalytic use in the sewage-disposal industry. [ABSTRACT FROM AUTHOR]

Poly(ionic liquids)(PILs) of the types poly(1-vinyl-3-alkyl imidazolium)X (where alkyl = ethyl, butyl & pentyl; X = Br − or OH − ) are synthesized and used for the preparation of stable silver, gold and nickel nanoparticles in solution. Studies pertaining to the dispersion of metal NP stabilized by PILs are discussed. The role of PILs is prominent as carriers towards reversible “solubility switch” of synthesized metal nanoparticles between aqueous and organic media by simple anionic metathesis. These PIL stabilized nanoparticles show great stability for longer period without agglomeration. At another role of employed PIL is the ability to tune the size of the metal NP, depending on the length of alkyl chains of PIL. UV–Visible, SEM and TEM techniques are used for the characterization and morphological study. PIL stabilized Ag NP shows very good antimicrobial activity at lower concentrations against Escherichia coli and Staphylococcus aureus . Ag NP are used in the catalytic reduction of aromatic nitro compounds with NaBH 4 and that of Ni NP for hydrogen transfer reduction of acetophenone in quantitative yields. [ABSTRACT FROM AUTHOR]