Reactive processing chain functionalization

Even in solution the relative rigidity of the polymer support can play a significant role in the reactivity of attached functional groups. Contrasting studies conducted with chloromethylated derivatives of poly(arylene ether sulfone) (Tg 175°C), phenoxy resin (Tg= 65°C) and polystyrene (Tg= 105°C) allow evaluation of chain rigidity effects. We have shown that the rates of quaternization of chloromethylated poly(arylene ether sulfones) and phenoxy resin deviate from the anticipated second order process at... 

Polymerization Reaction Processes. Polymerization reactions occur in one of two modes. In one, monomer molecules add together in a linear head-to-tail manner in each single chain reaction. This occurs when only two atoms in the molecular structure function as reactive sites. In the other mode, there is more than one reactive site or functional group in each molecule. Polymerization reactions occur between reactive sites rather than between molecules. The presence of more than one reactive site in a molecule means that the molecule can take part in as many chain reaction sequences, with the resulting polymer molecules being cross-linked perhaps thousands of times and to as many different polymer chains. The result can, in theory, be a massive block of solid polymeric material composed of a single, large molecule. 

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