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Interactions between poly(ethy1ene oxide) and phenol-formaldehyde resin play important roles in the mechanism by which the two polvmers improve fibre retention in the papermaking process. These were investigated at the concentration level and shear conditions found in this vrocess. The results indicste that the comvlex formed varies with pH and ionic strength over a very narrow range of conditions, and that the self association of the resin an important part in the quantity of resin io the complex.Because the amount of resin interactine with the ~olvethvlene oxide amears to be -. ----related to the molecular weight, and hence chain length, of the two polymers, cooperative binding of the polymers seems to be involved. A minimum size of the network was found to be necessary for the polymers to improve fibre retention.

Chemometrics was employed to study the effect of various reaction conditions on the graft copolymerization of acrylamide (AM) and diallyl dimethylammonium chloride (DADMAC) onto guar gum using the cerous sulfate and potassium persulfate complex initiation system. A two level full factorial design was used to study the effect of reaction parameters on percentage grafting (%G) and monomer conversion (%MC). Synthesized polymers were characterized using Fourier transform infrared spectroscopy (FTIR), 1H‐NMR (nuclear magnetic resonance spectroscopy), and 13C‐NMR and also were analyzed for differences in intrinsic viscosity and charge incurred with changing reaction conditions. The concentration of AM was observed to have the greater effect on %grafting. Interaction effects between the reaction temperature and concentration of AM were also found to be important. Under the reaction condition studied, the highest grafting (%G) was obtained for polymer 1 (0.7M AM concentration, 60°C reaction temperature, and 1M acid concentration). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

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