Carboxymethyl cellulose and composite films prepared by electrophoretic deposition and liquid-liquid particle extraction

Electrophoretic deposition (EPD) method has been developed for the controlled deposition of carboxymethyl cellulose (CMC) films. CMC has been utilized as a charging and film forming agent for the EPD of composite organic-inorganic films, containing aluminum hydroxide (AH) as a flame-retardant additive. Problems related to AH agglomeration were avoided using different liquid-liquid particle extraction strategies. It was found that lauryl gallate (LG) and hexadecylphosphonic acid (HDPA) exhibit remarkable adsorption on AH particles due to polydentate bonding mechanisms, and thus were used as efficient extracting agents. A conceptually new strategy has been developed for agglomerate-free processing of AH using HDPA as a capping agent for synthesis and an extractor molecule for liquid-liquid extraction. We demonstrated the EPD of composite CMC-AH films, which contained non-agglomerated AH particles, that were uniformly distributed in the CMC matrix. The AH content in the composite films was estimated from the thermal analysis data.