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This study is aimed at atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) using a novel catalyst. The bis-(2-dodecylsulfanyl-ethyl)-amine (SNS) tridentate ligand with mixed donor atoms was synthesized in high purity using inexpensive reagents and was reacted with copper(I) bromide to produce the CuBr/SNS catalyst. The catalyst mediated living polymerization of MMA yielding polymers with controlled molecular masses and narrow molecular mass distributions (PDI < 1.25). Also, the kinetic plot exhibited a linear increase of ln([M]0/[M]) versus time, indicating constant concentration of propagating radicals during the polymerization. The products were characterized by 1 H NMR, 13 C NMR, FT-IR, UV-VIS, GC and elemental analyses (CHNS) and by GPC.

Polybutadiene and hydroxyl terminated polybutadiene (HTPB) were epoxidized using in situ-generated dimethyl dioxirane (DMD) as an oxidant in the presence of nano-TiO 2 at 25 C. Reaction time and different percentages of catalyst/Oxone 1 (w/w) were also examined. The capability of different kinds of double bonds to be epoxidized was studied in detail at various reaction times, and the products were characterized using nuclear magnetic resonance ( 1 HNMR), 13 CNMR, and Fourier transform infrared (FT-IR) techniques, with no side reaction being detected. The results indicate that using nano-TiO 2 as a catalyst increases the epoxidation yield, especially of cis double bonds.

This paper reports on the epoxidation of hydroxyl-terminated polybutadiene (HTPB) using in-situ-generated dimethyl dioxirane (DMD) as an oxidant and nanoclay as a phase-transfer catalyst (PTC) at 25 • C. The aim was to consider in detail the functionality of isomeric C=C bonds under different reaction circumstances combining reaction time and different percentages of PTC/oxone (w/w). The data revealed the selectivity in the oxidation of cis double bonds in comparison with trans and vinyl ones. The products were characterized using 1 H-NMR, 13 C-NMR and FT-IR; no side-reactions were observed. In addition, it was found that the hydroxyl group of the polymer chain remained unaffected in the epoxidation reaction although no conditional controls were implemented. It was proven that this method is easy and convenient and that the reaction conditions are straightforward.

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