Epichlorohydrin cationic conversion

Bates noted that cationic sites in the resins are formed by conversion of the secondary amine groups to quaternary nitrogen by alkylation with the epichlorohydrin. On addition of the resin to a fiber slurry, ion exchange reactions occur that bind the resin firmly to the fiber through surface carboxyl groups. However, his work indicated that the resin... 

We wish to stress this point because one can find examples of improper treatment of experimental data in the literature on cationic polymerization. For instance, in a recent paper on the polymerization of a-epichlorohydrin the authors observed limited conversions of monomer 21). The polymer yield was increasing with decreasing temperatures. The authors assumed that the monomer concentration at the plateau was the equilibrium monomer concentration, and calculated thermodynamic parameters . The ring strain, expressed by AH thus obtained for a-epichlorohydrin was unrealistically low (only —23 kJ mol-1) when compared with heats of polymerization of other 3-membered cyclic ethers (cf. Table 2.7). Other reports on a-epichlorohydrin polymerization have shown that nearly quantitative conversions are possible even at higher temperatures, provided that termination is suppressed22 23). 

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