Polystyrene (PS) /ˌpɒliˈstaɪriːn/ is a synthetic polymer made from monomers of the aromatic hydrocarbon styrene. Polystyrene can be solid or foamed. General-purpose polystyrene is clear, hard, and brittle. It is an inexpensive resin per unit weight. It is a poor barrier to oxygen and water vapour and has a relatively low … See more Polystyrene was discovered in 1839 by Eduard Simon, an apothecary from Berlin. From storax, the resin of the Oriental sweetgum tree Liquidambar orientalis, he distilled an oily substance, that he named styrol, now called See more Polystyrene is commonly injection molded, vacuum formed, or extruded, while expanded polystyrene is either extruded or molded in a special process. Polystyrene copolymers are … See more Ordinary (homopolymeric) polystyrene has an excellent property profile about transparency, surface quality and stiffness. Its range of applications is further extended by copolymerization and other modifications (blends e.g. with PC and syndiotactic … See more Health The American Chemistry Council, formerly known as the Chemical Manufacturers' Association, writes: Based on scientific … See more In chemical terms, polystyrene is a long chain hydrocarbon wherein alternating carbon centers are attached to phenyl groups (a derivative of benzene). Polystyrene's … See more Polystyrene is relatively chemically inert. While it is waterproof and resistant to breakdown by many acids and bases, it is easily attacked by many organic solvents (e.g. it dissolves quickly when exposed to acetone), chlorinated solvents, and aromatic … See more Production Polystyrene foams are produced using blowing agents that form bubbles and expand the foam. In expanded polystyrene, these are usually hydrocarbons such as pentane, which may pose a flammability hazard in … See more WebNote: Tg is the property of amorphous polymers and the amorphous part of a semi-crystalline solid. What are the examples of polymers with high or low Tg? Polymers with …
Crystallinity in Polymers - pslc
WebThere is atactic polystyrene, and there is syndiotactic polystyrene. The former is totally amorphous and the later is very crystalline. Syndiotactic polystyrene has a very regular … WebNov 1, 2024 · The glass transition is a property of only the amorphous portion of a semi-crystalline solid. The crystalline portion remains crystalline during the glass transition. At … graham hill apartments mechanicsburg
Chapter 6: Processing Amorphous and Semi Crystalline
WebMay 13, 2024 · Poly(ʟ-lactide) (PLLA) films, even of high thickness, exhibiting co-crystalline and crystalline α phases with their chain axes preferentially perpendicular to the film plane (c⊥ orientation) have been obtained. This c⊥ orientation, unprecedented for PLLA films, can be achieved by the crystallization of amorphous films as induced by low-temperature … WebPVC has polar groups (chlorine), and is amorphous, therefore mixing well with various other substances. The required physical properties of end products (e.g., flexibility, elasticity, impact resistance, anti-fouling, prevention of microbial growth, anti-mist, fire retarding) can be freely designed through formulation with plasticisers and ... WebJan 1, 2007 · As a consequence, the density of the crystalline zone will typically be higher than that of corresponding Figure 11: Effect of the recycling numbers on resin density amorphous phases. For this ... china gray menu