this is a report on the study of high melt flow, highly isotactic polypropylene homopolymer synthesized in liquid monomer using a fifth generation ziegler-natta catalytic system. at highest catalyst productivity, the response of thecatalyst to hydrogen as chain transfer is studied. melt flow rate is controlled by hydrogen as chain transfer from 0.4 to 300 g/10min with changing the amount of hyd...

Hollow polymeric nanocapsules have attracted great interest in recent years due to their broad applications in controlledrelease carriers, catalysis, nanoreactors, and encapsulation of guest molecules. Polymeric nanocapsules have been typically fabricated via the selfassembly of block copolymers, 5 polymerization within lipid vesicles, emulsion polymerization, 14 and the sacrificial core-templa...

STATEMENT OF PROBLEM Most processed resin denture bases do not fit the cast accurately because of polymerization changes in the resin. The fit is more noticeable in the palate between the denture base and the cast. Therefore, development of a polymerization system that will improve the fit of a denture base to the cast is lack of worth considering to improve the fit and retention of the denture...

Chemotaxis requires localized F-actin polymerization at the site of the plasma membrane closest to the chemoattractant source, a process controlled by Rac/Cdc42 GTPases. We identify Dictyostelium RacB as an essential mediator of this process. RacB is activated upon chemoattractant stimulation, exhibiting biphasic kinetics paralleling F-actin polymerization. racB null cells have strong chemotaxi...

In general terms, submicron particles can be prepared either by disintegration of larger entities, or by synthesis from small building blocks such as atoms, ions or molecules. By comparison to disintegration techniques, the latter approach provides efficient access to particles down to the nanometer size regime; and it can allow for the controlled synthesis of particles in terms of size, size d...

A new method to synthesize integral carbon monoliths with a controlled channel morphology has been developed in this work by combining 3D-printing technology and sol–gel polymerization.

The activity of cerium alkoxide complexes supported by a Schiff base ligand was controlled using redox reagents during the ring-opening polymerization of L-lactide. The rate of L-lactide polymerization was modified by switching in situ between the cerium(III) and cerium(IV) species.

Microwave mediated RAFT polymerization leads to ultra-fast polymerizations, whilst keeping excellent control over molecular weights and molecular weight distributions; this is the first example of such a dramatic effect of microwaves on living radical polymerization kinetics, and it shows the potential for chemists to produce very well controlled polymers in a matter of minutes.

Polymerization-induced formation of amphiphilic diblock copolymer vesicles is performed in water at high concentrations by a single-step nitroxide-mediated controlled free-radical emulsion polymerization of 4-vinylpyridine, initiated by a water-soluble poly(sodium acrylate) macroalkoxyamine at alkaline pH.

Polymer layer growth by free radical graft polymerization (FRGP) and controlled nitroxide-mediated graft polymerization (NMGP) of polystyrene was achieved by atmospheric pressure hydrogen plasma surface activation of silicon. Kinetic polystyrene layer growth by atmospheric pressure plasma-induced FRGP (APPI-FRGP) exhibited a maximum surface-grafted layer thickness (125 A after 20 h) at an initi...