CHAPTER 11: Rubber Functionalized with Halloysite Loaded with Antioxidants and Antibacterials

Halloysites have been used as inorganic reinforcements in rubber matrices to prepare various kinds of nanocomposites at low cost. The nanocomposites possess improved mechanical, dynamic mechanical, thermal and other functional properties endowed by the addition of halloysites, broadening the application of the nanocomposites in industrial and biomedical fields. Aging and bacterial colonization are two main problems that affect the long-term usage of rubber. Sustained release of antioxidant and antibacterials are needed to realize a sustained and on-demand antioxidative and antibacterial ability respectively for a rubber system. Loading the halloysites’ lumens with antioxidants or antibacterials and then compounding the loaded tubes into the rubber matrix allows a sustained release of the loaded substances. Various halloysites–rubber composites and those with antioxidants or antibacterials loaded halloysites have been fabricated. The release of antioxidants or antibacterials from the nanocomposites could be tuned by the tube end-stoppers or the clogging of the polymeric matrix. Antioxidant-loaded halloysite doped into rubber enhances the anti-aging properties of the rubber for at least 12 months. The antibacterial-loaded HNTs doped in a rubber matrix represents a promising candidate for both industrial and biomedical devices to prevent bacterial colonization during long-term use.