The amylose/amylopectin ratio is an important factor influencing the mechanical properties of starch-based bioplastics especially since amylose affects the degree of crystallinity and entanglement of the product. Starch sources with increased amylose content are typically related to an increase in tensile strength and a decrease in strain in the bioplastic and are therefore desired. An all-amylose starch has been genetically produced for the purpose. On the other hand, high amylopectin content is correlated with higher strain as a result of its structural characteristics e.g. high molecular size. As per suggestions on best reagents and proportions, The content of amylose and amylopectine in starch varies and largely depends on the starch source. Corn has the highest amylose content and especially high amylose corn of about 70% content. Most starch-based bioplastics are therefore from corn starch. The reagents are mostly Propan-1, 2, 3-triol, Hydrochloric acid 0.1 mol/dm3 and Sodium hydroxide 0.1 mol/dm3 .

Bio - degradable plastics may be either ( a ) photo-degradable or oxo - degradable plastics which disintegrate into small pieces when exposed to sunlight/oxygen ; ( b ) semi - biodegradable; blends of starch and polyethylene or ( c ) 100% biodegradable refers only to those materials which are consumed by microorganisms such as bacteria, fungi and algae. These microorganisms breakdown the polymer chain which is ultimately converted to biomass. Biodegradable polymers are those that capable of undergoing decomposition into carbon dioxide , methane, water, inorganic compounds or biomass by actions of microorganisms. Starch based bioplastics are plastics derived from renewable biomass sources, such as vegetable fats, and oils, corn starch, straw, wood chips, food wastes. Not all bioplastics are biodegradable, the biodegrade ones are usually derived from sugar derivatives , including starch, cellulose and lactic acid. For more details consult en.mwikipedia.org

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