Atom transfer radical index

One of successfully applied polymerization technique in grafting-from approach is atom transfer radical polymerization ATRP [5]. ATRP can be used for controlled polymerization of many vinyl monomers i.e. acrylates, acrylonitrile or monomers containing different functional groups. Most of them can be polymerized by a traditional radical polymerization, however ATRP allows to obtain polymers with precise value of molecular weight (M ) and polydispersity index (PDI). 

Atom transfer radical polymerization was investigated to construct triblock (TB) materials, as shown in Figure 6.5. Polyphenylene (PP) with benzyl chloride as the end-capped functional group was firstly prepared as the macroinitiator, and then styrene was added with CuCl catalysts [9]. TB polymers were obtained with very low polymer dispersity index and afforded to sulfonation afterward. Clear phase-separated morphology was an evidence of the as-prepared TB polymer and thus exhibited good potential for some distributed junction photovoltaic applications. 

Silane radical atom transfer (SRAA) was demonstrated as an efficient, metal-free method to generate polystyrene of controllable molecular weight and low polydispersity index values. (TMSlsSi radicals were generated in situ by reaction of (TMSlsSiH with thermally generated f-BuO radicals as depicted in Scheme 14. (TMSlsSi radicals in the presence of polystyrene bromide (PS -Br), effectively abstract the bromine from the chain terminus and generate macroradicals that undergo coupling reactions (Reaction 70). 

The electrophilicity index of an atom-transfer reaction, mechanism (6.vni), can be calculated from four different combinations of the ionisation potentials and electron affinities of the atoms or radicals involved in the reaction. Two of them make use of the properties of only one species, 7p(A) and E (A) or 7p(C) and 7i (C), and the other two involve cross... 

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