Although most monomers can polymerize through different propagation pathways, polymerization-initiating systems that switch from one mode to another are rare. In this study, we demonstrate enamine-based organic electron donors (OEDs) constitute the first able initiate either free-radical or anionic polymerization under simple, mild, and safe conditions. While direct electron-transfer reduction ...

N-Methylpyridinium esters derivatives of 2-methylbenzothiazole hemicyanine dyes photoinitiators/photosensitizers derived from N-propyl-3-[N-2-methylbenzothiazolo]-4-pyridyno phenylacetic acid ester diiodide and N-propyl-3-[N-2-me]thylbenzothiazolo]-4-pyridino diphenylacetic acid ester diiodide were synthesized and proposed as new photoinitiators of polymerization of 2-ethyl-(2-hydroxymethyl)-1,...

titanium dioxide (tio2) nanoparticles, with an average size of about 45 nm, were encapsulated by polystyrene using in situ nitroxide mediated radical polymerization   in the presence of 3-aminopropyl triethoxy silane (aptes) as a coupling agent and 2, 2, 6, 6-tetramethylpiperidinyl-1-oxy  as a initiator. first, the initiator for nmrp was covalently bonded onto the surface of titanium dioxide na...

a copolymer of styrene and methyl styrene was synthesized by nitroxide - mediated “living” free radical polymerization )nmp). n-bromosuccinimide was used as a brominating agent to obtain a copolymer with bromine as its end group. this brominated copolymer was used as macro initiators for atom transfer  radical  polymerization  (atrp).  chemical  modifcation  of  the  clay  and transformation of...

Abstract: When the size of a polymerization locus is smaller than a few hundred nanometers, such as in miniemulsion polymerization, each locus may contain no more than one key-component molecule, and the concentration may become much larger than the corresponding bulk polymerization, leading to a significantly different rate of polymerization. By focusing attention on the component having the l...

INTRODUCTION Photo-induced polymerization'-6 is concerned with absorption of ultraviolet radiation to produce an unstable excited species. Subsequent formation of a free radical by rearrangement, fragmentation or energy transfer, followed by attack upon a monomer, leads to polymerization. Yamamoto and Oster7 have indicated that photo-induced polymerization resembles polymerization initiated by ...

Traditional solution acrylic polymers for pressure sensitive adhesives (PSA) are synthesized using conventional free radical initiation systems based upon organic peroxide or azo compounds 1 . Such syntheses are heat activated and employ solvent reflux temperatures during the polymerization process. The resulting acrylic polymers are formed with a relatively broad molecular weight distribution ...

The mechanical fracture of polymer produces polymeric free radical chain-ends, by which liner block copolymers have been synthesized. A diblock copolymer of microcrystalline cellulose (MCC) and poly 2-hydroxyethyl methacrylate (pHEMA) was produced by the mechanochemical polymerization under vacuum and room temperature. The fraction of pHEMA in MCC-block-pHEMA produced by the mechanochemical pol...