Complexing agents, grafting

XXXI. Alternating Copolymer Graft Copolymers VI. Synthesis in the Absence and Presence of Complexing Agents... 

Alternating copolymer graft copolymers are also produced when comonomers that yield alternating copolymers with but not without a complexing agent are copolymerized in the presence of a complexing agent and a suitable polymer, either with or without a free-radical precursor (14). 

Similarly, an alternating copolymer containing complexed complexing agent may be prepared from a comonomer mixture and then mixed with different comonomers to form an alternating copolymer graft copolymer. 

Cellulose-water may act as a matrix and promote the development of arrays of comonomer charge transfer complexes (19). The cellulose acts not only as a substrate for such alignment but also as a complexing agent. The matrix of complexes may be represented as shown in I (styrene-methyl methacrylate) and II (butadiene-acrylonitrile). The radical-, thermal-, and radiation-induced graft polymerizations involve homopolymerization of comonomer complexes rather than copolymerization of uncomplexed monomers. 

Mercury is a highly toxic element and its removal and analytical detection are important. Dithiocarbamate-incorporated monosized polystyrene-based microspheres (2 pm) have been prepared (2043) and used for the selective removal of mercury(ll) from aqueous solutions. The absorption ability increases with pH (2044). Related to this, dithiocarbamate grafted onto dried silica gel have been shown to be highly effective for the removal of mercury from waste solutions containing various complexing agents (145). 

The first drugs in this class to be introduced into clinical practice are simple derivatives of 5-nitrofurfural (18). Thus, the oxime is known as nitrofuroxime (19) while the semicarbazone is called nitrofurazone (20). In order to maintain better control over the distribution and metabolism of these antibacterial agents, increasingly complex side chains and rings have been grafted onto the hydrazone. 

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