Regio- and stereoselectivity control in the polymerization of 1,3-conjugated dienes is much interest importance. We report herein for first time isospecific trans-1,4-selective living (E)-1,3-pentadiene (EPD) by a C5H5-ligated yttrium catalyst (C5H5)Y(CH2C6H4-NMe2-o)2/[Ph3C][B(C6F5)4], which afforded crystalline isotactic-trans-1,4-polypentadiene showing good elastic properties without vulcaniz...

A series of dimethylaluminum complexes (L1a-i )AlMe2 (2a-i, where HL1a-i = 2-(2'-ArNH)phenyl-4-R1-oxazoline) bearing chiral, bidentate anilido-oxazolinate ligands have been prepared and characterized. Six of the complexes, in the presence of an alcohol cocatalyst, are shown to be active initiators for the stereoselective ring-opening polymerization of rac-lactide in toluene solution and under b...

Polylactide (PLA) represents one of the most promising biomedical polymers due to its biodegradability, bioresorbability and good biocompatibility. This work highlights the synthesis and characterization of PLAs using novel diethylzinc/gallic acid (ZnEt₂/GAc) and diethylzinc/propyl gallate (ZnEt₂/PGAc) catalytic systems that are safe for human body. The results of the ring-opening polymerizatio...

Poly(2-vinylpyridine 1-oxide) inhibits the cytotoxic effects of quartz in cell cultures but the syndiotactic polymer behaves differently from the isotactic and atactic polymers. In each case approximately 1-0 mg/m2 of the polymer represents the adsorption maximum. No difference has been found between the adsorption isotherms of the stereoisomeric polymers or the stability of the adsorbed layers...

Poly(mandelic acid), PMA, is an aryl analogue of poly(lactic acid), PLA, and a biodegradable analogue of polystyrene. Preparation of stereoregular PMA is reported for the first time in this work using a pyridine-mandelic acid adduct (Py·MA) as an organocatalyst for the ring-opening polymerisation (ROP) of the cyclic O-carboxyanhydride, manOCA. Polymers with narrow polydispersity index and excel...

This paper focuses on the calculation of interfacial tension two systems: low-density polyethylene with isotactic polypropylene and high-density syndiotactic polypropylene. For this, three methods to measure are compared: use Palierne's model, Gramespacher Meissner's both based additional elasticity or long relaxation times brought by shape recovery dispersed phase, ab-initio calculation, which...