Growth Polymers

The rate of formation of radicals will depend on a number of features, including the concentration of initiator, temperature and the presence of other agents. Since subsequent stages of polymer growth occur almost instantaneously it is the relative slowness of this stage which causes the overall conversion times in most polymerisations to be at least 30 minutes and sometimes much longer. 

The results for e/fcTj, = 1.8 are shown in Fig. 4.7. Again, their importance lies in the correct qualitative features for polymer growth. However, it has recently been demonstrated that even with this simple model a fit of experimental growth rate and thickness data (of the polymer PEEK) can be achieved [166],... 

Uranyl Nitrate Influence on Polymer Growth. The effect of a solute such as uranyl nitrate on this polymer formation is so complex that the net effect on the polymer growth rate cannot be predicted. Experimentally, it is observed that the rates of growth at given initial HNO3 concentration are always slower in the presence of as indicated by the solid curve in... 

Figure 2. Determination of reaction order for Pu(IV) polymer growth stage at 50° C. Sloped 3 for all HNO, concentrations indicated. (Reprinted with permission from Ref. 2.)...

Reflux Experiments. More recent efforts have been directed at a quantitative evaluation of those parameters that affect polymer growth, namely acidity, plutonium concentration, temperature, and reflux action. The last is an interesting example to illustrate since the admission of low acid condensates or diluents to a Pu(IV) solution causes some polymer formation even when the bulk solution is otherwise acidic enough to prevent any measurable degree of hydrolysis. 

Parametric studies, polymer growth. 237-39 Partial enthalpy of vaporization,... 

Reflux experiments, polymer growth 237-39 Regression analysis, stability constants... 

The theory of reversible helical polymerization of proteins has been fully described by Oosawa and Asakura (1975). The following equation describes polymer growth ... 

Polymer growth J(c) showed nonlinear monomer concentration dependence in the presence of ATP (Carrier et al., 1984), while in the presence of ADP, the plot of J(c) versus monomer concentration for actin was a straight line, as expected for reversible polymerization. The data imply that newly incorporated subunits dissociate from the filament at a slower rate than internal ADP-subunits in other words, (a) the effect of nucleotide hydrolysis is to decrease the stability of the polymer by increasing k and (b) nucleotide hydrolysis is uncoupled from polymerization and occurs in a step that follows incorporation of a ATP-subunit in the polymer. Newly incorporated, slowly dissociating, terminal ATP-subunits form a stable cap at the ends of F-actin filaments. 

Keywords. Poly(3-hydroxybutyrate), Metabolic sequences, Fine regulation, Poly(3HB) cycle, Strategic survival polymer, Growth-associated synthesis, Energy-generating and -consuming synthesis, Optimization... 

Upon activation, the complex only has two d.v-coordination sites in the front one for monomer entry and the other for polymer growth... 

Multigrade batch processing, 20 703 Multigrade oils, 15 225 Multigrain model, of polymer growth, 26 528... 

Polymer growth, models of, 26 528-529 Polymeric a-oxygen-substituted peroxides, 18 459-460... 

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