ethylene was polymerized in slurry phase over a ticl4/mg(oc2h5)2 catalyst activated by al(c2h5)3. it was shown experimentally that mass transfer resistance has no effect on polymerization kinetics. after estimation ofthe active site concentration by inhibition method with carbon monoxide, the effects of polymerization temperature, monomer and cocatalyst  oncentrations and hydrogen were investig...

Background and Aim: Minimizing the polymerization shrinkage of composite resins is a critical goals in composite restorations. Many factors affect polymerization shrinkage. This study aimed to evaluate the effect of composite resin shade on polymerization shrinkage. Materials and Methods: In this in vitro study, 14 composite discs measuring 1.5×8 mm were fabricated. The samples were prepared u...

today laser has a lot of usage in medicine and dentistry. in the field of dentistry, laser is used in soft tissue surgery, sterilization of canals (in root canal therapy) and in restorative dentistry laser is used for cavity preparation, caries removal, sealing the grooves (in preventive dentistry), etching enamel and dentin, composite polymerization and removal of tooth sensitivity. the use of...

Cationic photo-initiated and polymerized epoxies are characterized by good adhesion, high modulus, zero volatiles, low shrinkage living polymerization characteristics. Radiation—cured acrylate resins rapid initial curing with increased strength. The combination of radiation-cured acrylates may present advantageous attributes. Thus, the system investigated is a hybrid epoxy/methyl three differen...

Abstract A unique UV-Curing method is provided for decontamination of radioisotopes on the surfaces which has radiation dealing facilities. In this acrylic resin was poured a contaminated simulated surface followed by UV irradiation. The interacted with and after polymerization, solidified then stripped off, leaving behind clean surface. present study proof-of-concept novel application methodol...

Samples of a commercially available polyphenyl ether (PPE) oil are irradiated in the mixed neutron and gamma radiation field Pavia TRIGA Mark II reactor, at irradiation doses ranging from 0.78 MGy to 7.8 MGy. The is nuclear grade product, whose resistance reported product specification based on cobalt-60 data. collection additional data reactor performed present work, motivated by need use this...

Radiation grafting of monomers on polymers is radical polymerization which usually takes place in viscous medium and quite often in a micro-heterogeneous semicrystalline matrix. The role of kinetic and structural factors in the graft polymerization was investigated. Grafting of styrene on polyethylene and polypropylene was initiated by radiation methods (direct irradiation of polymer and monome...

Abstract This review is the third part of a series reviews on hydrophobization lignocellulosic materials, relevant topic nowadays, due to need replace fossil fuel-based materials. The provides an overview materials by polymer adsorption, and both chemical radiation-induced grafting polymers. While adsorbed polymers are only attached surfaces physical interactions, grafted chemically bonded Radi...