Abstract
This research investigates the influence of?dditives-namely glycerol (20% 30% ?nd 40% wt) ZnO (0?nd 1 phr) ?nd coffee extract (0% 5% 7.5% ?nd 10% phr)-on the properties of poly(vinyl?lcohol) (PVA) film. The composite samples were prepared by blending using? twin-screw extruder?nd shaping through compression molding. The?ddition of glycerol yielded increased water solubility while? higher glycerol content resulted in reduced water?bsorption. Concurrently the glass transition temperature (Tg) melting temperature (Tm) ?nd crystallinity (Xc) exhibited? decrease leading to diminished tensile strength but elevated elongation?t break. A notable linear relationship between glycerol content?nd film crystallinity was observed. The incorporation of ZnO reduced water solubility?nd?bsorption enhancing tensile strength?nd elongation due to improved Xc?nd stress-transfer characteristics. Conversely the presence of coffee extract increased water solubility?nd?bsorption yet substantially compromised film strength?nd toughness by diminishing Xc?nd causing microstructure collapse. The findings suggest the potential use of PVA composite films for seedling planting with tailored properties?chieved through?dditive manipulation. ? 2023 Science Society of Thailand under Royal Patronage. All rights reserved.
