Order in purely organic network polymers is hard to achieve, as reversible, dynamic covalent bond formation is required. Strategies have focused on thermodynamically controlled transformations, as kinetics would not seemingly favour reversibility. Herein, we report formation of crystalline network polymers under kinetically favoured conditions by using quaternary ammonium salt linked networks. Charged bulky bridges align, even under fast reaction times (20 minutes) if the rotational freedom is granted. Adding vicinal methyl substituents blocks the ordering, hence forming amorphous networks. Raman experiments and SEM images reveal stacking of 2D layers.

Magnetic nanoparticles are promising in applications where magnetic separation is intended, although material losses via leaching mechanisms are often inevitable. Magnetic separations with widely available permanent magnets can effectively trap particles, leading to a complete removal of used or waste particles. In this report, we first demonstrate the synthesis of the thinnest (112.7 ± 16.4 nm) and most magnetic (71.96 emu g−1) barium hexaferrite (BaFe12O19, BHF—fridge magnet) via an organic solvent-free electrospinning procedure. When the fibers are then packed into a column, they clearly remove 12 nm magnetite (Fe3O4) nanoparticles quantitatively. The same BHF cartridge also removes more than 99.9 % As-treated magnetite nanoparticles at capacities up to 70 times of its weight. As a result, one liter of 150 μg L−1 As-contaminated water can be purified rapidly at a material cost of less than 2 US cents.

Amide based porous organic polymers were synthesized by the reaction of 1,3,5-benzenetricarbonyl trichloride with 2,4,6-triamino-1,3,5-triazine using two different solvents. Polyamide chains were derived from tri-functional monomers and their relative properties were compared in both media. These polymers were subjected to various analyses including FTIR, XRD, TGA, BET surface area and pore size analysis, FESEM and CO2 adsorption measurements. Thermal and chemical stability was achieved through strong amide building blocks in the polymer structure. The basic ring nitrogen and amide groups in the polyamide networks had the affinity to capture CO2. The maximum CO2 uptake of 2.99 cm3 g−1 (0.134 mmol g−1) at 273 K and 1 bar was obtained with the polyamide synthesized in DMAc–NMP (PA-1), revealing better efficiency than the polyamide prepared using 1,4-dioxane (PA-2) due to higher porosity and improved surface area. These thermally stable polyamides are anticipated to be good sorbents for CO2 capture in hostile environments.

Disulfide-linked covalent organic polymers (COPs) were prepared through catalyst-free oxidative coupling polymerization. Owing to the excellent swelling behavior, low cost, and efficient synthesis, these materials can be promising materials for removal of organics in concentrated streams. COPs show 1,4-dioxane uptake up to 1.8 g g−1.

Aromatic polyamide/organoclay nanocomposites were synthesized using the solution blending technique. Treatment of montmorillonite clay with p-phenylenediamine produced reactive organophilic clay for good compatibility with the matrix. Polyamide chains were prepared by condensing a mixture of 1,4-phenylenediamine and 4-4′-oxydianiline with isophthaloyl chloride under anhydrous conditions. These chains were end capped with carbonyl chloride using 1% extra acid chloride near the end of reaction to develop the interactions with organoclay. The dispersion and structure–property relationship were monitored using FTIR, XRD, FE-SEM, TEM, DSC and tensile testing of the thin films. The structural investigations confirmed the formation of delaminated and disordered intercalated morphology with nanoclay loadings. This morphology of the nanocomposites resulted in their enhanced mechanical properties. The tensile behavior and glass transition temperature significantly augmented with increasing organoclay content showing a greater interaction between the two disparate phases.