Carbamate pesticides, defined

Several authors have attempted to interpret the differences in adsorption behavior of different compounds within the same group of pesticides. Briggs (23) has studied the effect of changes in substituent groups in substituted phenylurea compounds and alkyl-N-phenyl carbamates on the partition of these compounds between solutions and soils in contact with solutions. He found a linear relationship between the logarithms of the partition coeflBcients and the Hammett constants and the Taft constants of the substituted phenylurea compounds. However, in alkyl-N-phenylcarbamates, linear relationships between the logarithms of the partition coefficients and the Hansch constants of the compounds are obtained. The Hansch constant (tt) is defined in the following way by Fujita et al. (24) ... 

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