Metal-metal cooperativity effects have been extensively explored in olefin polymerization, along with the design and preparation of many binuclear transition metal catalysts. However, their synthesis and the tuning of metal-metal distance are complicated and time-consuming. In this contribution, a supramolecular chemistry strategy was used to construct multinuclear olefin polymerization catalysts. Urea functional groups were installed into several α-diimine palladium catalysts to enable hydrogenbonding-induced self-assembly. Compared with methylated counterparts (devoid of supramolecular interactions), the assembled structures and their catalytic properties were affected by the concentration, ligand sterics, temperature, and solvents, which ultimately changed the polymerization properties. Furthermore, the introduction of azobenzene units into the catalyst framework gave rise to photoresponsive behaviors in the assembled catalysts. During ethylene polymerization and copolymerization with methyl acrylate, important parameters were easily modulated, including the activity, comonomer incorporation, polymer branching density, molecular weight, and molecular weight distribution. The introduction of supramolecular chemistry and photochemistry strategies to transition-metal-catalyzed olefin polymerization opens up new possibilities for the design of new polyolefin materials.

Heterogeneous catalysts have been dominant for industrial polyolefin production, offering many distinct advantages, such as controlling the morphology of the polymer and preventing reactor fouling. In this contribution, we designed several types of imine ligands bearing sodium-sulfonate ionic groups and the corresponding nickel/iron catalysts. These catalysts could be immobilized on SiO 2 with strong affinity and high catalyst loadings. The SiO 2 -supported catalysts behaved better than their homogeneous counterparts during ethylene polymerization with extremely high activity (2.6 × 10 4 kg• mol) and high thermal stability. In addition, the supported nickel catalysts generated free-flowing polyethylene with high molecular weight (M n up to 2.65 × 10 3 kg• mol -1) and excellent morphology control, indicating no reactor fouling due to the leaching of catalyst. Moreover, for copolymerization, immobilized nickel catalysts showed a higher tolerance of polar monomers, and the efficient copolymerization of ethylene with undecylenic acid was achieved with high activity (450 kg• mol) and a high incorporation ratio (up to 12.3%).

Removal of copper-cyanide complexes from electroplating industry effluent were studied by using an ion-exchange process. A kind of polypropylene strong alkaline anion exchange fiber was used to perform packed beds continuous experiments. The conditions of adsorption were wastewater pH value 9.0 and flow rate 90-120 BV•h-1 at room temperature. The packed beds were exhausted at 1300 bed volumes for copper-cyanide complexes The elution of copper-cyanide complexes from ion-exchange fiber was studied. The results showed that copper-cyanide complexes were easily eluted from ion exchange fiber using either 2.0 mol•L-1 NaNO3 or NaCl. With 1.0 mol•L-1 NaNO3 solution at 30 BV•h-1, the regenerating rate of copper-cyanide complexes was more than 95%.

Designing of new catalysts through structural modification, is a permanent dimension in catalysis. In this scenario, the limitations of pyrazolylimine, concerning to their low thermal stability and providing the polymer...