a fi zr-based catalyst of bis[n-(3,5-dicumylsalicylidene)-2′,6′­diisopropylanilinato]zirconium(iv) dichloride was prepared and used for polymerization of ethylene. the effects of reaction conditions on the polymerization were examined in detail. the increase in ethylene pressure and rise in polymerization temperature up to 35 oc were favorable for catalyst/mao to raise the catalytic activity as...

chitosan/polyethersulfone (cs/pes) composite membrane was prepared from casting chitosan solution on polyethersulfone substrate membrane. the substrate membrane was prepared by phase inversion technique using polyethersulfone (pes) and dimethylacetamide (dmac) as solvent with and without the addition of polyvinylpyrrolidone (pvp) as pore-forming agent. the effects of the composition of the c...

Blends of polyvinyl butyral (PVB) and polyethylene glycol dimethyl ether (PEGDME) with low molecular weight ( M ¯ w ${\bar{M}}_w$ = 250 g/mol) show two calorimetric (for PEGDME content higher than 11% by weight) mechanical glass transitions. Their substantial changes the relative components are explained considering self-concentrations both polymers determined from connectivity their own chains...

DB is a whitish to yellowish resin, characterized initially in terms of solubility, acid value, molecular weight (Mw), polydispersity index (Mw/Mn) and glass transition temperature (Tg). Neat plasticized films of DB (Damar Batu) are investigated for mechanical, water vapor transmission and moisture absorption properties. To improve the mechanical properties of the free films dibutyl sebacate, a...

solubility of high molecular weight n-paraffins in supercritical carbon dioxide has been a matter of interest to many researchers. however, not sufficient solubility experimental data are available although the methods by which the experimental data are obtained have many varieties. utilizing cubic equations of state is an effective method for solubility prediction of n-paraffins in supercritic...

during last two decades, polysaccharides such as alginate (alg) alone and in combination with other biopolymers are widely used in vaccine and drug delivery systems. the aim of the present work was to investigate the potential utility of microparticles made of alginate (alg) as new vehicles for improving nasal vaccine delivery. for this purpose, diphtheria toxoid (dt) was chosen as a model anti...