Organo-montmorillonite as a controlled release reservoir for triclosan in silicone elastomer: A flow micro-calorimetry and leaching study

Abstract

Organically modified montmorillonite (o-MMT) in a room temperature addition cured silicone elastomer (PDMS) has been found to control the release of 2,4,2′-trichloro-2′-hydroxy diphenylether (triclosan (TCS)) from the composite. The effect of o-MMT gallery polarity on controlled release was investigated via different intercalants and the interaction of triclosan with the o-MMT was investigated using flow micro-calorimetry (FMC). The latter was found not to be a universal predictor of controlled release activity of the composite as combined TCS and PDMS interactions with MMT/o-MMT leading to intercalation (observed using WAXS) and controlled release activity must also be considered. Southern Clay Products Cloisite® 15A (C15A) gave the most sustained release of TCS whilst also featuring a uniform gallery spacing in the composite. A pore structure based on self-assembled C15A intercalant alkyl tails is tentatively proposed. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.