Size effect of ZnO nanorods on physicochemical properties of plasticized starch composites

GUZ LUCAS; FAMA, LUCIA; CANDAL, ROBERTO J; GOYANES SILVIA

CARBOHYDRATE POLYMERS

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2017 vol. 157 p. 1611 - 1619

0144-8617

This work demonstrates that the size of ZnO nanorods (ZnONR) with similaraspect ratio determines several physicochemical and microbiological propertiesof thermoplastic starch composites (TPS/ZnONR) at a given concentration ofZnONRs. A combination of sol-gel and hydrothermal methods was developed tosynthesize ZnONR with different sizes but similar aspect ratios. Starchcomposites containing 1 wt.% of ZnONR were prepared by casting. Compositeswith smaller size nanorods (ZnONR-S) showed more efficiency in shieldingUVA radiation and, had a higher solubility and water vapor permeability thanthose with larger nanorods (ZnONR-L). Mechanical properties, biodegradabilityand antibacterial activity were also influenced by the size of the ZnONR. X-raydiffraction analysis showed that composites with ZnONR-S maintained thetypical B-V type starch structure, intensifying the V-type starch structure peaks,while composite with ZnONR-L induced the formation of an amorphousstructure, preventing starch retrogradation during storage. Properties affectedby nanorods size are fundamental in determining composite applications