Effect of surface property of halloysite on the crystallization behavior of PBAT

Halloysite (Hal), calcined Hal, and organosilane-modified Hal were used as filler for the preparation of Hal/PBAT nanocomposite. XRD, SEM, XPS, FTIR, DSC, POM, and Avrami, Jeziomy, Kissinger models were used to characterize the surface property of Hal and its effect on the crystallization morphology, structure and kinetics of nanocomposites. Hydrogen bonding, generated between -NH2 or -OH groups on surface of organosilane-modified calcined Hal or calcined Hal and C-(C=O)-O in ester of PBAT, efficiently enhanced the nucleation ability of Hal nanofiller, resulting in increment of crystallization temperature, decrease of half time, but retard the transport of PBAT molecules chains. The stronger the hydrogen bond was, the more remarkable such influence was. This study provides a promising approach of tailoring the surface characteristic of Hal to manipulate the crystallization of biodegradable aliphatic-aromatic polyesters, especially with extreme low loading of Hal nanofiller.