Defined with fast initial step

With many redox systems, coupled reactions take place that make it necessary to choose the appropriate system in accordance with the monomer and the polymerization conditions. If the redox reaction is slow, there will be a low yield of radicals and therefore a low polymerization rate. On the other hand, if the redox reaction is fast compared with the initiation step, the majority of initiating radicals will be consumed by radical termination reactions. Therefore, redox systems are modified by further additives. For example, heavy metal ions may be complexed with substances such as citrates, which adjust their reactivity to a reduced level. Hence, redox systems for technical polymerization are complex formulations which enable one to obtain optimum results at well-defined reaction conditions. 

Since a point of the MEP is uniquely defined by the value of the radius of the hypersphere, the step size appears not to be critical in our approach and one can carry out a fast uphill walk with a large step size. Every minimization step of the E function is an efficient procedure due to the application of a quasi-Newton algorithm and to the initial geometry guess, estimated as extrapolation from previous MEP points. 

Sulfonation of the common feedstocks proceeds with a highly exothermic instantaneous initial reaction, followed by a fast but not instant step that is also highly exothermic. The second reaction does not always proceed to completion (e.g., LAB, FAME) in the lower zone of a short residence time falling film reactor (FFR). For these organic feedstocks aging under well-defined conditions of temperature and reaction time is required. 

Synthesis ofm-silyl hydride-functionalized polymers The first critical step in this methodology is the preparation of well-defined, -silyl hydride-ftmaionalized polymers. For this purpose, the reaction of sec-butyllithium-initiated PSLi (Mn = 2200gmor M /Mn=l.02) with 2.3 molar equivalents of chlorodimethylsilane was effected in benzene at room temperature (see Scheme 21). A color change from red to colorless occurred within a few minutes, indicating a very fast reaction rate. The sUyl hydride end-funrtionalized polystyrene. 

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