Petroleum sources-based biodegradable polymers

As mentioned previously, biodegradable polymers can be derived from both petroleum and renewable sources. Both types of biodegradable polymers have attracted attention in the industry. Petroleum-based biodegradable polymers may help to overcome the accumulation of non-degradable plastic waste. However, renewable biodegradable polymers not only possess biodegradability, but the polymers are also derived from sustainable sources with environmental credit. 

Renewable resource-based polymers Petroleum-based biodegradable polymers Biodegradable polymer from mixed sources (Bio-/petrobased)... 

Bionanocomposites are an ecological alternative to conventional nanocomposites based on petroleum-derived polymers, as they are based on biodegradable polymers obtained from renewable resources. Biomass is the source of agropolymers like starch and cellulose and also of monomers used to chemically synthesize polymers like polylactic acid (PLA). Other kinds of biopolymers, e.g., xanthan gum and poly (hydroxyalkanoates), are produced by microorganisms. Even though most of the bionanocomposites reported in the hterature are based on layered sihcates, the number of examples illustrating the use of fibrous clays in the preparation of new bionanocomposites is growing rapidly. 

The naturally biodegradable polymers such as starch, chitosan and cellulose derived from natural sources have produced a number of interesting NR blends and IPNs. These blended systems have an advantage in that they create fewer waste disposal problems compared to the petroleum based polymeric materials. The use of stareh blends to enhance the biodegradability of conventional plastics has been reported by many researchers in order to reduce the environmental impaet of petroleum based plastic products and waste. The NR/maize stareh blends exhibited a decrease in their mechanical strength due to the speeifie properties of starch. However, the blended polymers showed a low interfaeial interaetion between the two phases due to the different polarity behaviour of the hydrophobic NR and the hydrophilic starch. 

The over growing environmental pressure caused by the wide spread consumption of petroleum based polymers and plastics has hastened the development of biodegradable and environmentally acceptable materials. Biopolymers derived from various natural resources such as proteins, cellulosics, starch and other polysaccharides are regarded as the alternate materials. Biodegradable polymeric materials derived from renewable sources are the most promising materials because of their easy availability and cost effectiveness. Biodegradable modified polysaccharides have been found to possess varied applications such as salt resistant absorption of water [109]. 

Recently, biogradable and renewably derived polymers have attracted much attention due to the environmental concerns and sustainability issues associated with petroleum-based polymers. Such a polymer is poly (lactic acid) (PLA), a biodegradable and bioabsorbable, renewably derived thermoplastic polyester extensively investigated over the lastest several decades. PLA is a compostable polymer derived from renewable sources. 

Biopolymers are polymers that were produced from renewable natural sources, which are biodegradable, and are not toxic. These can also be produced by biological systems (i.e., microorganisms, plants and animals) or chemically synthesized from biological starting materials (e.g., sugars, starch, natural fats, oils, etc.). These biopolymers are an alternative source to petroleum-based polymers traditional plastics. The biopolyesters have properties similar to traditional polyesters. Starch-based polymers are often... 

Starch may offer a substitute for petroleum-based plastics. A renewable degradable carbohydrate biopolymer that can be purified from various sources by environmentally sound processes, starch, by itself, has severe limitations due to its water solubility. Articles made from starch wiU swell and deform upon exposure to moisture. To improve some of its properties, in the past decades a number of researchers have often blended starch with hydrophobic polymers in the form of petroleum polymers, both to increase biodegradability and to reduce the usage of petroleum polymer. 

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