Synthesis of Bis (aminimides) and Their Properties

Abstract

A series of bis (aminimides) (BAI) with a general formula, [RCH (OH) CH₂NMe₂NCO] ₂Y, (R : n-C₄n-C₁₀, Y : - (CH₂) _n-and p-phenylene, n : 08) were prepared by the reactions of diesters of aliphatic and aromatic dibasic acids with aminimines derived from 1, 2-epoxyalkanes and 1, 1-dimethylhydrazine. The yields were 3040% for the aliphatic series and 7080% for the aromatic series. For the aromatic series, it was found that BAI and half aminimide esters were selectively obtained in high yields by the control of molar ratio of aminimide/carboxylic diester. Some surfactant properties of these products were examined and compared with those of corresponding monoaminimides (MAI), RCH (OH) CH₂NMe₂ NCOR'. BAI without methylene bridge between two aminimide groups have a high Krafft point and are insoluble in water at room temperature, while no Krafft point is observed for BAI with n=28. BAI except for the lower members show a characteristic cloud point in analogy with poly (oxyethylene) type nonionic surfactants. The cloud point decreases linearly with increasing n, but no appreciable effect of n on cmc, aqueous surface tension (γcmc) and molecular area (A0) of adsorption film at air/ water interface are observed. The cmc and γcmc of BAI are slightly higher than those of MAI (4, 5). A0 of BAI is about twice as large as that of MAI. BAI are generally inferior to MAI (4, 5) in wetting and foaming abilities.