Effect of various plasticizers and concentration on the physical, thermal, mechanical, and structural properties of cassava‐starch‐based films

Abstract

The present study investigated the effects of plasticizers (fructose, urea, tri-ethylene glycol, and triethanolamine) with different concentrations on the physical, thermal, and mechanical properties of cassava-starch-based films. The film samples were prepared using casting methods. The moisture content, water solubility, and water absorption of the films increased with increasing plasticizer content. Fructose-plasticized films show excellent water resistance compared to other plasticizers. Film plasticized with 30% fructose showed the highest density (1.74 g/cm 3 ), but the lowest water content (10.96%) and water absorption (110%). Films containing fructose presented smooth surfaces without pores. The glass transition temperatures of the plasticized film also decreased with increased plasticizer content, irrespective of the plasticizer type. The relative crystallinity decreased with increasing plasticizer content. The film plasticized by 30% fructose presented higher relative crystallinity (0.31). The increase of plasticizer concentration resulted in a decrease of tensile strength, but increased elongation at break of the film samples. Film plasticized with 30% fructose showed the highest tensile strength (4.7 MPa) and tensile modulus (69 MPa). Thus, fructose was the most efficient plasticizer agent among the various plasticizers used in this study. High contents of plasticizer resulted in changes in the properties of the films. Overall, it can be concluded that the plasticizer type and concentration significantly influence the properties of cassava-starch-based film.

Physical, Mechanical, Morphological, and Barrier Properties of Elephant Foot Yam Starch, Whey Protein Concentrate and psyllium Husk Based Composite Biodegradable Films

“…However, at higher starch: glycerol ratio the films were unable to maintain integrity. Similar results for lower solubility at low plasticizer concentration have been reported by Edhirej . According to Gutierrez et al strong hydrogen bond between the hydroxyl groups of starch chains and glycerol molecules decrease sensitivity to water and hence, solubility.…”

Low Transition Temperature Mixtures (LTTM) Containing Sugars as Potato Starch Plasticizers

“…High values of EB is result of great size of combined plasticizer. Similar results were obtained in the work of Zdanowicz et al Using pure sugars for starch plasticization resulted in brittle materials …”

“…Similar results were obtained in the work of Zdanowicz et al [12] Using pure sugars for starch plasticization resulted in brittle materials. [6,37] Figure S2 depicts strain-stress curves for TPS films with different LTTM at the same molar ratio of sugar to glycerol. As we can see, TPS/LTTM containing sucrose exhibited the highest TS, YM, and EB and the values were: 5.2 MPa, 293 MPa, and 86.5%, respectively (Table S2, SI).…”

Sugar palm nanocrystalline cellulose reinforced sugar palm starch composite: Degradation and water-barrier properties

“…Besides that, as the size of SPNCCs decreased, the percentage of the water absorption also decreased. Additionally, film with big particle size of SPNCCs exhibited greater tendency to absorb water which possibly due to a lower response to stress [33]. In this study, water absorption tests revealed that stabilizing the mixtures with SPNCCs decreased the water absorption capacity.…”