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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.
Dynamic mechanical analysis (abbreviated DMA) is a technique used to study and characterize materials. It is most useful for studying the viscoelastic behavior of polymers . A sinusoidal stress is applied and the strain in the material is measured, allowing one to determine the complex modulus .
An ABS 3D bell manufactured with a 3D printer. Engineering plastics [1] are a group of plastic materials that have better mechanical or thermal properties than the more widely used commodity plastics (such as polystyrene, polyvinyl chloride, polypropylene and polyethylene).
Stress relaxation describes how polymers relieve stress under constant strain. Because they are viscoelastic, polymers behave in a nonlinear , non-Hookean fashion. [ 1 ] This nonlinearity is described by both stress relaxation and a phenomenon known as creep , which describes how polymers strain under constant stress.
Polymer nomenclature is generally based upon the type of monomer residues comprising the polymer. A polymer which contains only a single type of repeat unit is known as a homopolymer, while a polymer containing two or more types of repeat units is known as a copolymer. [22] A terpolymer is a copolymer which contains three types of repeat units ...
For some materials, e.g. elastomers and polymers, subjected to large deformations, the engineering definition of strain is not applicable, e.g. typical engineering strains greater than 1%, [1] thus other more complex definitions of strain are required, such as stretch, logarithmic strain, Green strain, and Almansi strain.
The characterization of mechanical properties in polymers typically refers to a measure of the strength, elasticity, viscoelasticity, and anisotropy of a polymeric material. The mechanical properties of a polymer are strongly dependent upon the Van der Waals interactions of the polymer chains, and the ability of the chains to elongate and align ...
The improvement of mechanical properties and thermal stability is and has always been an important goal in the research of new plastics. Since the early 1960s, the development of high-performance plastics has been driven by corresponding needs in the aerospace and nuclear technology. [3]