The New Jersey Institute of Technology's
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Title:	Flow behavior of molten polymer blends
Author:	Maciejewski, Kryspin Pawel
View Online:	njit-etd1972-020 (IX, 147 pages ~ 8.1 MB pdf)
Department:	Department of Chemical Engineering and Chemistry
Degree:	Master of Science
Program:	Chemical Engineering
Document Type:	Thesis
Advisory Committee:	Griskey, Richard G. (Committee chair) Salamone, Jerome J. (Committee member) McCormick, John E. (Committee member)
Date:	1972-02
Keywords:	Polymers and polymerization
Availability:	Unrestricted
Abstract:	An experimental study of molten polymer blends was made using the Instron Capillary Rheometer. The materials investigated were two phase blends of non-crystalline polymers (poIymethylmethacrystate-low Mw-polyvinylacetate, polyvinylacetate-polystyrene, polymethylmethacrylate-low Mw-polystyrene, polymethylmethacrylate-high Mw-polystyrene), crystalline polymers (polyethylene-polypropylene) and combinations of non-crystalline-crystalline polymers (polyethylene-polystyrene). Two methods of sample preparation were used, blending of a polymer pair in a molten state by the use of Brabender blender, and a simple manual blending of pellets in desired proportion. The Brabender blended polymer pairs show lower viscosities, this is interpreted molecularly as a result of a reduction of the amount of chain entanglement on shearing of the material. In all cases deviation from the additive change of viscosity with change in composition occurs. It was established that the addition of a small quantity of one polymer to another causes drop in viscosity; this is attributed to the lubricating affect of the polymer added in small quantity. Small quantity of one polymer added to another causes also an increase in the melt elasticity of the blend. Extrudate melt fracture phenomena of blended polymer pairs was also studied.