Molecular weight distribution treatment process

Figure 2. Shows the influence of degradation under processing for SBS copolymer 414C. (a) The molecular weight distribution (MWD) before processing, (b) The MWD after 41 min treatment in a Brabender Plasto-graph, Walzenkneter 30 temperature 180°C and rate of rotation 110 rotations per minute (with 1 % lonox added).

In Section 5.2.1.1 we provide an overview of the classical treatment of polymerization kinetics. Some aspects of termination kinetics are not well understood and no wholly satisfactory unified description is in place, Nonetheless, it remains a fact that many features of the kinetics of radical polymerization can be predicted using a very simple model in which radical-radical termination is characterized by a single rale constant. The termination process determines the molecular weight and molecular weight distribution of the polymer. In section... 

When activated carbon is applied prior to conventional treatment processes, the composition of DOM components is the same as that in the source water. However, the concentration and molecular weight distribution of DOM in water changes during treatment operations since DOM components are selectively removed by conventional treatment processes. As a result, the composition of DOM in contact with activated carbon depends on the location of application. Conventional water treatment processes preferentially remove hlgli molecular weight and more hydrophobic components of DOM from water [17,19], Therefore, when activated carbon is applied in filters after conventional treatment process, it is exposed to a DOM mixture that consists of smaller molecular weiglit and more hydrophilic DOM components, having a lower DOC concentration as compared to the raw water (Fig. 1). 

Eventually, at high 7, Wg becomes unity. In the neighborhood of the gel point, the molecular weight distribution is extremely broad, and the smallest species are the last, on the average, to become attached to the network as - 1. When there is an initial molecular weight distribution or if the cross-linking process is acconipanied by simultaneous scission of molecules, the treatment is more complicated. 

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