Polypropylene barium sulfate

Schaefer et al. (19) studied the interphase microstructure of ternary polymer composites consisting of polypropylene, ethylene-propylene-diene-terpolymer (EPDM), and different types of inorganic fillers (e.g., kaolin clay and barium sulfate). They used extraction and dynamic mechanical methods to relate the thickness of absorbed polymer coatings on filler particles to mechanical properties. The extraction of composite samples with xylene solvent for prolonged periods of time indicated that the bound polymer around filler particles increased from 3 to 12 nm thick between kaolin to barium sulfate filler types. Solid-state Nuclear Magnetic Resonance (NMR) analyses of the bound polymer layers indicated that EPDM was the main constituent adsorbed to the filler particles. Without doubt, the existence of an interphase microstructure was shown to exist and have a rather sizable thickness. They proceeded to use this interphase model to fit a modified van der Poel equation to compute the storage modulus G (T) and loss modulus G"(T) properties. [Pg.435]

Other materials that have been incorporated into polymers to modify mechanical and other properties include calcium sulfate in styrene-butadiene rubber [174-178], barium sulfate in polyethylene [179], barium sulfate in polypropylene [174], aluminum in epoxy resins [178], kaolinite-muscovite in polyvinyl chloride-polybutyl acrylate... [Pg.82]

General discussions of the effect of reinforcing agents on the thermal properties of polymers include glass fiber-reinforced polyethylene terephthalate [28], multiwalled carbon nanotube-reinforced liquid crystalline polymer [29], polysesquioxane [30, 31], polynrethane [31], epoxy resins [32], polyethylene [33], montmorillonite clay-reinforced polypropylene [34], polyethylene [35], polylactic acid [36, 37], calcium carbonate-filled low-density polyethylene [38], and barium sulfate-filled polyethylene [39]. [Pg.95]

Dense fillers are used when heft, weight, or sound/ vibration damping is required. Heft is the perception of quality associated with products that feel substantial in the hand. Dense formulations are used in washing machine counterweights to reduce vibration. Formulations include iron slag in polypropylene or epoxy. Dense fillers include barium sulfate (density 45 g cm ), magnetite (density 5.0 g-cm ), micaceous iron oxide (density 5.0 g cm ), and metals (density 8-20 g-cm ). [Pg.531]