Methods for the determination of the molecular weight of nylons are described. The active end groups of alcohol-soluble nylons are determined either potentiometrically or conductometrically. The amine end groups of alcohol-insoluble, phenol-soluble nylons may be determined by conductometric titration in the solvent phenol-alcohol-water. Carboxyl end groups of the latter nylons are determined by dissolving the polymer in benzyl alcohol at 175°C. and titrating with potassium hydroxide, using phenolphthalein as indicator.

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In the 120 krad/h, 60Co-γ radiolysis of air-free, anhydrous solutions of ferric hexafluoroacetylacetonate (Fe(HFA)3) in toluene at 27 °C, G(—Fe(HFA)3) = G(Fe(HFA)2) = 1.05 ± 0.03 molecules/100 eV and G(HHFA) = 0 where Fe(HFA)2 is radiolytically inert ferrous hexafluoroacetylacetonate and HHFA is hexafluoroacetylacetone. G(H2) = 0.13 ± 0.03 is not affected by Fe(HFA)3 while G(CH4)is reduced from 0.0088 &([a-z]+); 0.0020 to 0.0052 ± 0.0020 and [Formula: see text] is increased from 0.102 ± 0.019 to 0.307 ± 0.026 by Fe(HFA)3. Activation energies for the radiolytic formation of Fe(HFA)2, H2, CH4, and [Formula: see text] in the temperature range −95 to 27 °C, are 670 ± 130, 0, 1200 ± 900, and 1280 ± 25 cal mol−1, respectively.G(—Fe(HFA)3) = 1.05 represents the total yield of radicals scavenged since at the concentrations of solute used in the radiolyses the quantum yield for the disappearance of Fe(HFA)3 by reaction with solvent S1 and/or T1 states, generated by flash photolysis, is negligible [Formula: see text] Radicals trapped by Fe(HFA)3 are••CH3 (G ≈ 0.004) and unknown radicals (G ≈ 0.4) which are capable of combining with [Formula: see text] does not scavenge [Formula: see text] radicals (G ≈ 0.6). The formation of H2 in scavenger inaccessible spurs and CH4 and [Formula: see text] outside spurs has been confirmed.

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