Modification of montmorillonite by cationic polyesters

Novel types of polyester hydrochlorides and polyesters were synthesized from N-octyl- or N-methyldiethanolamine and organic acid chlorides with varying chain length. Their structure, molar masses and glass transition temperatures were determined. Montmorillonite (MMT) was modified by cation exchange with the polyester hydrochlorides. The basal spacing was not significantly influenced by the length of organic acid chain but increased with the length of the alkyl group attached to nitrogen atom. Cation ratio of MMT and hydrochloride must have been at least 1:3 for quantitative cation exchange, indicating that only a part of polycation chain adheres to MMT surface. Hydrophobicity and organic content increased with increased exchange ratio, reaching approximately constant levels at ratios above 1:3.