Thermoplastic elastic olefins

COPs differ from simple polyester thermoplastics, which are typically hard crystalline polymers of organic dibasic acids and diols. COPs have an excellent combination of properties and are accordingly priced higher than thermoplastic elastic olefins (TEOs) or thermoplastic vulcanizates (TPVs). 

PLGA poly(lactic-co-glycolic acid) TEO thermoplastic elastic olefin... 

Syndiotactic polystyrene (sPS) represents an important achievement in olefin polymerization catalysis. Syndiotactic PS is an industrially relevant thermoplastic material produced by Dow Chemical and Idemitsu Kosan Co. under the tradenames Questra and Xarec , respectively. Industrial interest on sPS originates from the remarkable properties exhibited by this highly crystalline polymer. The high melting temperature, 270 °C, the relatively fast crystallization rate (at least much faster than that of iPS), the high heat resistance, the low dielectric constant, the high elastic modulus, and an excellent resistance to chemicals explain the industrial interest for this material. Syndiotactic PS was considered as an innovative new resin option for the automotive, electrical, and electronic markets, appliances such as... 

Commercial IPNs have been developed to combine useful properties of two or more polymer systems. For example, high levels of silicone have been combined with the thermoplastic elastomer (TPE) based on Shells Kraton styrene-ethylene/butadiene-styrene TPE and Monsantos Santoprene olefin TPE. These IPN TPEs are said to provide the biocompatibility and release properties of silicone with tear and tensile strength up to five times greater than medical-grade silicone. Thermal and electronic properties and elastic recovery are also improved. 

Thermoplasts are non-cross-linked materials whose application temperatures lie below and whose processing temperatures lie above their glass-transition temperatures (if amorphous) or melting temperatures (if partially crystalline). Above these temperatures, their viscosities are lower by orders of magnitude the materials can consequently be heat-formed. At the processing temperatures, however, they still show elastic characteristics, and are, therefore, viscoelastic substances. As a rule, they show no plasticity, so that the name thermoplast is incorrect. In order to be used as a thermoplast, a material must consist of non-cross-linked or, at the most, weakly cross-linked molecules. Typical thermoplasts are, according to their behavior, poly(ethylene) and other poly(olefins), poly(styrene), poly(vinyl chloride), poly(methyl methacrylate), and polyamides. 

Figure 2 Compression set (elastic recovery under compressive deformation) at 70 °C for an E-LAO random copolymer, flexible polyvinylchloride (f-PVC), thermoplastic polyurethanes (TPUs), and thermoplastic vulcanizates (TPVs). Reproduced with permission from Wenzel, T. T. Arriola, D. J. Carnahan, E. M. et at. In Metal Catalysts in Olefin Poiymerization. Topics in Organometallic Chemistiy, Guan, I., Ed. Springer-Verlag Berlin, Germany, 2009 Vol. 26. ...

Thermoplastics are resins that repeatedly soften when heated and harden when cooled (conditions that refer to fusibility ). Most thermoplastics are soluble in specific solvents and can bum to some degree. Softening temperatures vary with the polymer type and grade. Care must be taken in application conditions not to exceed the heat distortion temperature of the plastic, wherein the plastic begins to soften and potentially warp. Typical thermoplastics utilized in the automotive arena include, poly(olefins)—for example, poly(propylene) (PP) and poly(ethyl-ene)—nylon, acrylic, acetal, poly(styiene), poly(vinyl chloride) (PVC), poly-(sulfone), and the like. Also within this group are highly elastic, flexible resins known as thermoplastic elastomers (TPEs). 

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