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A thermoplastic, or thermosoftening plastic, is any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling. [ 1 ] [ 2 ] Most thermoplastics have a high molecular weight .
Thermoplastics are made of covalent bond molecule chains, which are held together by weak interactions (e.g., van der Waals forces). The weak intermolecular interactions lead to easy processing by melting (or in some cases also from solution ), but also make the polymer susceptible to solvent degradation and to creep under constant load.
One important classification of plastics is the degree to which the chemical processes used to make them are reversible or not. Thermoplastics do not undergo chemical change in their composition when heated and thus can be molded repeatedly. Examples include polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyvinyl chloride (PVC). [15]
Thermoplastic elastomers show advantages typical of both rubbery materials and plastic materials. The benefit of using thermoplastic elastomers is the ability to stretch to moderate elongations and return to its near original shape creating a longer life and better physical range than other materials.
LDPE has SPI resin ID code 4 Schematic of LDPE branching structure. Low-density polyethylene (LDPE) is a thermoplastic made from the monomer ethylene.It was the first grade of polyethylene, produced in 1933 by John C. Swallow and M.W Perrin who were working for Imperial Chemical Industries (ICI) using a high pressure process via free radical polymerization. [1]
Once the casting kits are returned, Campana crafts a personalized brace, or prosthetic, out of thermoplastic material. Despite his extremely successful business today, this was not a planned ...
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).
However, a sandwich made at home with low-fat lunch meat on whole-grain bread, a dozen baby carrots, a small individually sized box of raisins for dessert and a can of diet soda can be assembled ...