Author :
Publisher :
ISBN 13 :
Total Pages : 2 pages
Book Rating : 4.:/5 (893 download)
Book Synopsis Preparation of Highly Uniform Low Density Polystyrene Foams and Their Characterization by :
Download or read book Preparation of Highly Uniform Low Density Polystyrene Foams and Their Characterization written by and published by . This book was released on 2004 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt: High Internal Phase Emulsion polystyrene foams have been made at Los Alamos National Laboratory for the past decade. As target designs become more complex the demands placed on the foams are more stringent. Parts need to be machined from 30 mg/cm3 foams to a thickness of 50 [mu]m within a couple of microns. Containing upwards of 97% air, these foams are to withstand extraction with ethanol to remove the wax utilized as a machining aid yet retain their dimensional stability. At low densities, less than 50 mg/cm3, voids are a problem. To determine a formulation that reduces void content and allows minimum shrinkage, experimental design was utilized. We also developed image analysis techniques that allow us to quantify the amount of voids in the system and the surface finish of the foam. In order to machine these low density foams to the tolerance required with an optimum surface finish, the foams are backfilled with Brij{reg_sign} 78, an alcohol soluble wax. After a part is machined the Brij{reg_sign} is leached out with ethanol. The dimensional stability of the foam was found to be independent of the formulation of the foam. The filler that was used to aid in machining did have a significant impact on the final properties of a machined part.
