The ring size of cyclic amines influences the yield, Mw and PDI values of polynorbonene obtained via ROMP using [RuCl2(PPh3)2(amine)x] as the starting complex.

Copolymers from norbornene (NBE) with norbornadiene (NBD) were synthesized via ring opening metathesis copolymerization varying the mole fractions of the comonomers (0.8 : 0.2; 0.6 : 0.4; 0.4 : 0.6; 0.2 : 0.8) for a total monomer quantity of 5000 equivalents/[Ru]. The batch reactions were performed with [RuCl2(PPh3)2(amine)] complex types as precatalysts, where amine is perhydroazepine (1) or piperidine (2), in CHCl3 (2 mL) in the presence of ethyl diazoacetate (5 μL) for different intervals of times (5, 30, 60, and 120 min) at 40°C. The copolymers were characterized by 13C NMR. Quantitative yields of isolated materials were obtained from solutions with NBD : NBE 0.8 : 0.2 mole fraction in the presence of 1, decreasing to 70% for NBD : NBE 0.2 : 0.8 solutions. Concerning 2, the yields were 70% at most. Polymeric materials obtained with 1 were less soluble in CHCl3 than those synthesized with 2. The dependence of the reaction yields and occurrence of crosslinking on the starting NBE : NBD proportion related to reactivity of the complexes 1 and 2 were discussed. A few differences in the amines such as ancillary ligands were sufficient to change the reactivity of the {RuCl2(PPh3)} moiety complex to provide copolymers with different compositions. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

An excess of lactose and lactose-rich milk permeate is produced by the dairy industry. The use of these waste products has been investigated for the preparation of sugar-based hydrogels. An environmentally friendly, atom-economical reaction conducted in water with minimal waste was successfully applied in the synthesis of lactose methacrylate. Lactose methacrylate was copolymerized with the methacrylic acid generated as a byproduct of the initial synthesis using photoinduced polymerization to yield hydrogels. The photopolymerization was facilitated by lowintensity UV light (365 nm) without the need for an exogenous photoinitiator. Hydrogels with varied water uptake, rheological, and mechanical properties could be prepared by the use of different methacrylic anhydride loadings in the synthesis of lactose methacrylate.