The homogeneous non-catalytic hydrogenation of cis-1,4 poly(isoprene), isotactic cis-1,4 poly(1,3-pentadiene) and syndiotactic cis-1,4 poly(1,3-pentadiene) with diimide, formed by thermal decomposition of para-toluenesulfonylhydrazide, is examined. Perfectly alternating ethylene/propylene copolymers having different tacticity (i.e., isotactic and syndiotactic), which are difficult to synthesize...

isotactic poly (1-butene), ipbu-1, was synthesized by using a metallocene catalyst. the thermodynamic phase behavior of polymer–organic solvents systems is very important in every polymer application.  in this paper, the solid–liquid equilibrium of ipbu-1 with different organic solvents (1-heptyne, cyclo octane) was studied by a mathematical model. by considering the experiments temperature-mol...

We report the design, synthesis, morphology, phase behavior, and mechanical properties of semicrystalline, polyolefin-based block copolymers. By using living, stereoselective insertion polymerization catalysts, syndiotactic polypropylene-block-poly(ethylene-co-propylene)-block-syndiotactic polypropylene and isotactic polypropylene-block-regioirregular polypropylene-block-isotactic polypropylene...

The crystal structures of highly crystalline isotactic and syndiotactic hydrogenated poly(norbornene)s [H-poly(NB)s], synthesized by the stereospecific ring-opening metathesis polymerizations norbornene followed complete hydrogenation, have been determined for first time on basis X-ray diffraction data analyses. similarity difference chain conformation packing mode in lattice clarified among th...

Isotactic poly (1-butene), ipbu-1, was synthesized by using a metallocene catalyst. The thermodynamic phase behavior of polymer–organic solvents systems is very important in every polymer application.  In this paper, the solid–liquid equilibrium of ipbu-1 with different organic solvents (1-heptyne, cyclo octane) was studied by a mathematical model. By considering the experiments temperature...

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...

We report an effective strategy for the synthesis of semi-crystalline block copolyethers with well-defined architecture and stereochemistry. As an exemplary system, triblock copolymers containing either atactic (racemic) or isotactic (R or S) poly(propylene oxide) end blocks with a central poly(ethylene oxide) mid-block were prepared by anionic ring-opening procedures. Stereochemical control wa...

The persistence length of isotactic poly(hydroxy butyrate) was measured using small-angle neutron scattering. The value obtained from these measurements reflects a high degree of local chain persistence. If this local persistence is accounted for, scattering from these chains can be globally fit with Gaussian scaling. A global scattering function, the unified equation, is used, which decomposes...