styrene nanocomposites were synthesized by in-situ atom transfer radical polymerization at 110oc. the variations of monomer conversion and the linearity of semilogarithmic kinetic plot, some signs of living polymerizationand constant radical concentration in the reaction medium, were revealed by gas chromatography technique (gc). according to the gel permeation chromatography (gpc) results, the...

The effects of polymerization kinetics and chemical miscibility on the crosslinking structure and mechanical properties of polymers cured by visible-light initiated free-radical/cationic ring-opening hybrid photopolymerization are determined. A three-component initiator system is used and the monomer system contains methacrylates and epoxides. The photopolymerization kinetics is monitored in si...

The polymerization of serpins is at the root of a large class of diseases; the molecular structure of serpin polymers has been recently debated. In this work, we study the polymerization kinetics of human neuroserpin by Fourier Transform Infra Red spectroscopy and by time-lapse Size Exclusion Chromatography. First, we show that two distinct neuroserpin polymers, formed at 45 and 85°C, display t...

In thermal frontal polymerization, the interplay between heat diffusion and Arrhenius type reaction kinetics gives rise to a propagating reactive front that is effectively sustained through a system positive feedback mechanism. We seek to understand how spatial confinement affects the system dynamics and overall polymerization kinetics. We find that with increasing confinement of the system, th...

The origin of the genetic code in the context of an RNA world is a major problem in the field of biophysical chemistry. In this paper, we describe how the polymerization of amino acids along RNA templates can be affected by the properties of both molecules. Considering a system without enzymes, in which the tRNAs (the translation adaptors) are not loaded selectively with amino acids, we show th...

Photochemistry serves as a wonderful means to facilitate various chemical reactions and is indeed unique in its powerful ability to meet the energetic requirements for conducting processes that would not be accomplished using thermal counterparts. In this work, a novel photocatalyzed Fe-based atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) was performed under UV irradia...

Reversible addition-fragmentation chain transfer polymerization (RAFT) was used to prepare polymer brushes grafted onto silica nanoparticles. Novel RAFT-silane agents were prepared that contained both an active RAFT moiety and a silane coupling agent. RAFT agents were anchored to silica nanoparticles by the functionalization of colloidal silica with the RAFT-silane agents. RAFT polymerizations ...

We analyse the dynamics of overlapping antiparallel treadmilling microtubules in the presence of crosslinking processive motor proteins that counterbalance an external force. We show that coupling the force-dependent velocity of motors and the kinetics of motor exchange with a bath in the presence of treadmilling leads generically to oscillatory behavior. In addition we show that coupling the p...

Actin polymerization is important for vesicle fission during clathrin-mediated endocytosis (CME), and it has been proposed that actin polymerization may promote vesicle fission during CME by providing direct mechanical forces. However, there is no direct evidence in support of this hypothesis. In the present study, the role of actin polymerization in vesicle fission was tested by analyzing the ...

Biodegradable four-arm star-shaped poly(lactic acid) (4sPLA) was synthesized from l-Lactic acid (l-LA) and pentaerythritol (PENTA), the polymerization kinetics studied. The effects of reaction time, temperature molar ratio on 4sPLA were discussed. molecular structure characterized by Fourier transform infrared spectroscopy (FTIR) 1H nuclear magnetic resonance spectra (1H-NMR). results showed th...