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Biodegradable polymers are classified into three groups: medical, ecological, and dual application, while in terms of origin they are divided into two groups: natural and synthetic. [18] The Clean Technology Group is exploiting the use of supercritical carbon dioxide , which under high pressure at room temperature is a solvent that can use ...
All polymers are made of repetitive units called monomers. Biopolymers often have a well-defined structure, though this is not a defining characteristic (example: lignocellulose): The exact chemical composition and the sequence in which these units are arranged is called the primary structure, in the case of proteins.
Polymer degradation is the reduction in the physical properties of a polymer, such as strength, caused by changes in its chemical composition.Polymers and particularly plastics are subject to degradation at all stages of their product life cycle, including during their initial processing, use, disposal into the environment and recycling. [1]
Susceptibility to biodegradation is highly dependent on the chemical backbone structure of the polymer, and different bioplastics have different structures, thus it cannot be assumed that bioplastic in the environment will readily disintegrate. Conversely, biodegradable plastics can also be synthesized from fossil fuels. [4] [12]
All biodegradable polymers should be stable and durable enough for use in their particular application, but upon disposal they should easily break down. [citation needed] Polymers, specifically biodegradable polymers, have extremely strong carbon backbones that are difficult to break, such that degradation often starts from the end-groups.
By definition, biodegradable materials are formed or organic compounds which can thus be broken down by living organisms, such as bacteria, fungi, or water molds, and reabsorbed by the natural environment. [13] Whether a material is biodegradable is determined by its chemical structure, not the origin of the material from which it is made. [14]
Biodegradable bags still strong enough to carry shopping after three years in the ground show that 'biodegradability' isn't all it's cracked up to be. When biodegradable plastic is not ...
The definition of bioplastics is still up for debate. The phrase is frequently used to refer to a wide range of diverse goods that may be biobased, biodegradable, or both. This could imply that polymers made from oil can be branded as "bioplastics" even if they have no biological components at all. [5]