Biodisintegratable Attempts have been made to embed a biodegradable trait into synthetic polymers so that they turn into mulch. These compounds perform badly in landfills through lack of moisture, slightly better when composted. Radical improvements have produced plastics, now commercially available, that degrade 100% less than 2 months after being discarded. Research continues into further control of the start of degradation.
Biodegradable 100% biodegradable rather than biodisintegratable. PHA (polyhydroxyalkanoate), a member of the polyester family discovered in 1925, is ‘manufactured’ directly by micro-organisms. Since then scores of bacteria that produce this organic polymer have been found, including PHBs (polyhydroxybutyrates), one of the first to be commercially available. PHA plastics can be moulded, melted and shaped like petroleum-based plastics, and have the same flexibility and strength. The same production methods can be used, e.g. melt-casting, injection moulding, blow moulding, spinning and extrusion. Manufactured under the name Biopol in Europe by ICI and PHBV in the United States. Too expensive for routine use for soft-drink bottles or grocery bags, but the cost should drop with full-scale production.
Bioregenerative Union Carbide researchers have produced a type of polycaprolactone film that completely biodegrades within 3 months� leaving no residues. Research into paper products laminated with layers of corn-based cellulose materials prove they can resist water for 6 to 8 hours and could serve as containers for drinks and fast-food items.
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