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Polymer chemistry is a sub-discipline of chemistry that focuses on the structures, chemical synthesis, and chemical and physical properties of polymers and macromolecules. The principles and methods used within polymer chemistry are also applicable through a wide range of other chemistry sub-disciplines like organic chemistry , analytical ...
One process for making PET uses bis(2-hydroxyethyl) terephthalate, [citation needed] which can be synthesized by the esterification reaction between terephthalic acid and ethylene glycol with water as a byproduct (this is also known as a condensation reaction), or by transesterification reaction between ethylene glycol and dimethyl ...
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]
For lack of nitrogen and phosphorus they produce a kilogram of PHA per three kilograms of sugar. The simplest and most commonly occurring form of PHA is the fermentative production of poly-beta-hydroxybutyrate [poly(3-hydroxybutyrate), P(3HB)], which consists of 1000 to 30000 hydroxy fatty acid monomers.
A propagation cycle is not initiated because each growth step requires the assistance of light. [11] Photopolymerization can be used as a photographic or printing process because polymerization only occurs in regions which have been exposed to light. Unreacted monomer can be removed from unexposed regions, leaving a relief polymeric image. [6]
Polymer engineering is generally an engineering field that designs, analyses, and modifies polymer materials. Polymer engineering covers aspects of the petrochemical industry, polymerization, structure and characterization of polymers, properties of polymers, compounding and processing of polymers and description of major polymers, structure property relations and applications.
A plastics fire in Indiana spewed various toxic chemicals into the air, including hydrogen cyanide and benzene, according to test results from the Environmental Protection Agency.. Officials said ...
The physical properties [31] of polymer strongly depend on the length (or equivalently, the molecular weight) of the polymer chain. [32] One important example of the physical consequences of the molecular weight is the scaling of the viscosity (resistance to flow) in the melt. [33]