Production of biodegradable plastic from cassava grown in Uganda and investigation of it's biodegradability and properties

Abstract

There has been an urgency of production and use of biodegradable plastics which are also known as biopolymers. In this research, the bioplastic made was out of cassava grown in Uganda. The extraction of cassava starch was manually done and a powder that was white in colour was obtained after complete dewatering and of the starch under the sun. From the starch, a biopolymer film was produced by addition of glycerol (10ml), water (100ml) and vinegar (10ml) in the presence of mild heat. The obtained film had a noticeable smell of vinegar, white in colour, transparent and flexible. It's characteristics were therefore similar to those of the traditional plastic. Biodegradability being a major aim of this research both the percentage carbon content and the percentage organic matter content of known weights taken from the main sample of bioplastic film was determined using the carbon test procedure. The percentage carbon content of samples of weights 0.07g and 0.05g was found to be 14.53% and 14.96%. On the other hand, the percentage organic matter content was 25.05% and 25.79% which are reasonably good in accordance to the weights of the samples taken. For the composting, it took eight days for complete decomposition of the bioplastic to occur. However the disintegration of the sample was vivid on day two and nearing total disintegration and decomposition was seen on day five. The soil used was muddy (filled with suitable amounts of water) and also exposed to humid conditions. Tests on the sample were done to see the effect of water on it which proved that cold water affects the film strength of the bioplastic film by gradually deteriorating it whereas hot water at 85°C dissolved the film after continuous stirring. From literature, the melting point of cassava made bioplastic is 80°C which is close to that of the bioplastic dissolution in the water. In acid and base, deterioration of the film strength was observed rather rapidly more than that in cold water.