Halogen Containing Polymers

This type of plasticization is important and several groups of polymers have been suggested for this method polymer hydrocarbons polymer halogen-containing hydrocarbons polymers containing ester groups polyvinyl ethers and acetals, and some other polymers of different constitution. 

O = HALOGEN-FREE POLYMERS = HALOGEN-CONTAINING POLYMERS... 

Modifiers. Modifiers can be added to reduce the molecular mass of the polymer. Halogen-containing compounds such as carbon tetrachloride, carbon tetrabromide, bromoform, or thiol such as butyl or dodecyl thiol are commonly used modifiers [21]. 

The designation miscible indicates that some (not all) members of the family have been reported miscible with the indicated halogen-containing polymer. 

Meta.1 Oxides. Halogen-containing elastomers such as polychloropreae and chlorosulfonated polyethylene are cross-linked by their reaction with metal oxides, typically ziac oxide. The metal oxide reacts with halogen groups ia the polymer to produce an active iatermediate which then reacts further to produce carbon—carbon cross-links. Ziac chloride is Hberated as a by-product and it serves as an autocatalyst for this reaction. Magnesium oxide is typically used with ZnCl to control the cure rate and minimize premature cross-linking (scorch). 

NLO materials (16 and 17) (Fig. 13) have been obtained from polyurethanes by the incorporation of sidechains with boron chromophores.37 The dihydroxy ligand of an azobenzene ligand containing a dimesityl boron acceptor was reacted in a polycondensation fashion with the diisocyanate groups of the polyurethanes to yield the desired polymers. Halogen displacement and transmetallation reactions have been utilized in the development of extended ir-conjugated systems of tri-9-anthrylborane with dendritic structures.38 In one (18) (Fig. 14) of the novel compounds, three identical... 

In halogen-containing polymers, the multifunctional zinc borate can function as a flame retardant, smoke suppressant, and afterglow suppressant. 

Reduction of polymer flammability is of broad interest for applications ranging from plastics to textiles. For polyesters, given their inherent instability towards water at elevated temperatures, and the high temperatures of manufacture, many classes of flame-retardant (FR) agents, including most halogen-containing materials, are impractical. Phosphate esters, capable of incorporation into the polymer backbone, were pioneered by Hoechst AG, and continue to be the materials of choice [84, 85],... 

A graft copolymer is a branched polymer containing a polymer chain derived from one monomer to which are attached one or more polymer side chains of another monomer. ATRP produces a graft copolymer when the initiator is a polymer with one or more halogen-containing side groups ... 

An existing polymer with an appropriate end group can be reacted with an alkoxyamine for instance, alkoxide polymerization of ethylene oxide yields a hydroxyl-terminated polymer that undergoes substitution (in the presence of sodium hydride) with a halogen-containing alkoxyamine. 

RAFT has also been used to produce graft polymers. The grafting from method is achieved by reacting a halogen-containing polymer such as styrene p-chloromethy I styrene copolymer with sodium dithiohenzoate to obtain a polymeric dithioester, which is an initiator in RAFT polymerization (Sec. 3-15d) [Quinn et al., 2002]. 

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