Studies on the Properties of Photo/Bio-Degradable Ldpe with Benzophenone and Hydrolysed Starch

Abstract

Maize starch was acid hydrolyzed at 50–60°C for 6 hours. Reduced viscosity for raw starch, hydrolyzed starch (HS) and glucose were determined. DSC tests were done to determine the melting point of the modified starch. LDPE of MFI 2 g/10 min was blended with this hydrolyzed starch at various proportions of 3–20% (wt%), photo-degradable additive – benzophenone (3%) and glycerol (3%) as compatibilizer using a twin screw extruder. The formulations made using HS were easy for processing and since the MFI was increased, the starch added, proved to be hydrolyzed, Tubular blown film was extruded using blown film extruder. LDPE with hydrolysed starch are processable into thin films (< 250 microns). The films obtained were tested for various mechanical tests like tensile strength, elongation at break, etc. The mechanical properties like tensile strength and elongation at break were lowered. Tear strength and dart impact strength were lowered. Also accelerated UV weathering and compost biodegradation tests were done on all the samples. Scanning Electron Microscope images were taken before and after UV weathering and also after biodegradation to determine the morphological changes on the samples. The samples were highly photo/biodegradable and hence will not pollute the environment.