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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 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]
Biodegradation of any plastic is a process that happens at solid/liquid interface whereby the enzymes in the liquid phase depolymerize the solid phase. [71] Certain types of bioplastics as well as conventional plastics containing additives are able to biodegrade. [ 72 ]
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]
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]
A simple way to monitor the change in viscosity, and thus, the extent of the reaction, in a curing process is to measure the variation of the elastic modulus. [7] To measure the elastic modulus of a system during curing, a rheometer can be used. [7] With dynamic mechanical analysis, the storage modulus (G') and the loss modulus (G) can be ...
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 ...
As a corollary, temperature strongly affects the physical behavior of polymers in solution, causing phase transitions, melts, and so on. The statistical approach to polymer physics is based on an analogy between polymer behavior and either Brownian motion or another type of a random walk , the self-avoiding walk .