Biopolymers and Bioplastics

Bioplastics and Biocomposites

Bioplastics are mouldable plastics made up of biomolecule compounds synthesized mostly by microbes or by genetically modified plants. These plastics are obtained from renewable resources and are not petroleum based compared to conventional plastics. Bioplastics are similar to plastics but with added benefits of biodegradability and biocompatibility. Most commonly produced industrial bioplastics are polylactic acid (PLA) and polyhydroxyalkanotes (PHA). Polylactic acid differs from most thermoplastic polymers since it is derived from renewable resources that include corn or sugar cane. It can be used for substituting pre-existing polymers with relatively low production cost. PLA is the second largest bioplastic in terms of mass production. It has a wide range of applications, with the most common ones being, bottles, plastic films and biodegradable medical devices. Since, PLAs are thermoplastics they have exiting applications in 3D printing.

Biocomposites are synthetic or biopolymers that are reinforced with natural/biofibers. Natural fibers such as jute, pinapple leaf fiber, hemp and various grasses are combined with polymer matrices from both renewable and non-renewable resources to form composites such as glass epoxies, glass-polypropylene etc. these naturally occurring natural fibres are bound to the polymers using epoxy, polyurethane or unsaturated polyester resins. The burgeoning area of applications for biocomposites is in housing products, automotive parts and packaging. There are challenges in replacing conventional glass reinforced plastics with biocomposites which includes design of materials which exhibit structural and functional stability during usage and storage but with the added advantage of environmental degradation upon disposal making them green materials. Car manufactures look for the biocomposites that deliver similar performance as conventional composites with lesser weight.