PHYSICOCHEMICAL PROPERTIES OF MODIFIED STARCH BASED FILMS OBTAINED BY EXTRUSION AND THERMO-COMPRESSION

OCHOA-YEPES, OSWALDO; GONZÁLEZ-SELIGRA, PAULA; GOYANES, SILVIA; GUZ, LUCAS; FAMÁ, LUCÍA

Workshop; III Workshop de Polímeros Biodegradables y Biocompatibles; 2018

Physicochemical properties of thermoplastic films based on modified starches obtained by extrusion and thermo-compression was investigated. Carboxymethylation (CMS) and acid hydrolysis (HS) modifications of native cassava starch (NS) were done. Films with NS, CMS, HS and a combination of the modified starches (HS/CMS), with biobased plasticizers, were evaluated. Compared to native starch films, HS presented increments in water vapor permeability (WVP), water content (WC) and water solubility (S). On the other hand, both CMS and HS/CMS films showed the lowest values of WVP, WC and S. These differences are consequence of the decrease of amylose molecular weight of HS and of the different form of packed of starch molecules due to the carboxyl group in CMS films.