The data on the effect of ethylene concentration on polymerization rate for several modifications of modern highly active titanium–magnesium catalysts TiCl4/MgCl2 are presented. These catalysts differ in titanium content and conditions of support preparation, activities, and the shape of kinetic curves. It is found that the observed order of polymerization rate with respect to ethylene in the r...

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...

A new method to prepare nanostructured hybrid hydrogels by incorporating well-defined poly(oligo (ethylene oxide) monomethyl ether methacrylate) (POEO(300)MA) nanogels of sizes 110-120 nm into a larger three-dimensional (3D) matrix was developed for drug delivery scaffolds for tissue engineering applications. Rhodamine B isothiocyanate-labeled dextran (RITC-Dx) or fluorescein isothiocyanate-lab...

A series of ABA triblock copolymers, consisting of double-bond-containing poly(phenoxyallene) (PPOA), poly(methyl methacrylate) (PMMA), or poly(butyl acrylate) (PBA) segments, were synthesized by sequential free radical polymerization and atom transfer radical polymerization (ATRP). A new bifunctional initiator bearing azo and halogen-containing ATRP initiating groups was first prepared followe...

The synthesis of a linear polyisobutylene is achieved for the first time by free radical polymerization. reaction was performed in environmentally friendly conditions, i.e., an aqueous medium using cyclodextrin solubilizer, around room temperature. This mild and straightforward polymerization resulted predominantly polymer with low dispersity. Isobutylene also copolymerized acrylamide via this ...