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Non-isocyanate polyurethane (NIPU) is one of the hot spots in the scientific research of polyurethane. In this work, mechanically regulable NIPU were prepared by ring-opening polymerization of cyclic carbonates via diamines. Cyclocarbonates with different functionalities were firstly synthesized by thiol-ene click reaction, which was characterized through nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy. The controllable mechanical performance of NIPU films was obtained by the structure of the diamines and the functionality of the thiol groups. The results of swelling and differential scanning calorimetry experiments suggested that the control of functionality and reactivity endowed the material with an adjustable crosslinking density. The Young's modulus of the material could be regulated from 51.3 to 765.1 MPa. Furthermore, the studied films also showed good thermal stability. The present study provides some guidance for the preparation of non-isocyanate polyurethane coatings for different application scenarios. [ABSTRACT FROM AUTHOR]

A crosslinkable ABA triblock copolymer was synthesized from allylic methacrylate (AMA) monomer using a poly(ethylene oxide)-based macromolecule as both an initiator and emulsifier. The 'two-step' controlled/living radical polymerization can be conducted via activator generated by electron transfer (AGET) atom transfer radical polymerization (ATRP). Cheap and commercially available N,N-dimethyldodecylamine (DMDA) was found to be a good ligand for the AGET ATRP reaction. The linear ABA triblock copolymer that contains pendent allylic groups can undergo crosslinking under UV irradiation conditions, which indicates that the environmentally friendly method has potential applications in UV curing coatings and UV curing inks, etc.. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Three fluorinated block copolymers have been prepared successfully in emulsion system using a surface-active atom transfer radical polymerization (ATRP) initiator disodium 4-(10-(2-bromo-2-methylpropanoyloxy)decyloxy)-4-oxo-2-sulfonatobutanoate ( 1). The copolymerization can be conducted in 'one pot' under activator generated by electron transfer (AGET) ATRP in emulsion conditions, thus greatly simplifying the operations and workup. The anionic surface-active ATRP initiator ( 1) and nonionic surfactant OP-10 may form synergistic stabilizers that effectively guarantee stability of the final latex. The ATRP follows first-order kinetics and has living/controlled characteristics based on the researching results of polymerization of trifluoroethyl methacrylate (TFEMA). Surface studies indicate that the fluorinated block copolymers reveal lower surface energy and stronger hydrophobic property compared with those non-fluorinated polymers. The decreasing order of surface energy of the polymers is: polystyrene (PS) > polytrifluoroethyl methacrylate- block-polystyrene (PTFEMA- b-PS) > polyhexafluorobutyl methacrylate- block-polystyrene (PHFBMA- b-PS) > polydodecafluoroheptyl methacrylate- block-polystyrene (PDFHMA- b-PS) > polydodecafluoroheptyl methacrylate (PDFHMA). Fluorinated homopolymer PDFHMA and copolymer PDFHMA- b-PS exhibits relatively low-surface energy, which is ascribed to the long and flexible DFHMA units containing in the polymers. [ABSTRACT FROM AUTHOR]