Pierson, O. L.
Rohm & Haas Co., Philadelphia, Pa.
Pages: 7 Published: Jan 1965
A vocabulary of important properties of rigid polymers is presented and compared with some older materials such as metals, wood and glass. Those properties which affect the design of parts intended for long-term loading are discussed in detail. Application of data with the use of classic formulas from mechanics is illustrated.
Methods for fabricating prostheses from rigid polymers are summarized. Sheet plastics may be formed by heating to about 300 to 400 F. Commercial molding is usually not adaptable to making a few parts, but blocks of polymers are available for the machining of a variety of items. The materials may be worked by conventional wood or metal shop tools. Parts should be annealed and equilibrated prior to service to minimize dimensional changes due to environmental changes. Strong adhesives join plastics to themselves, but attachment to other materials requires careful attention. Autoclave sterilization distorts many polymers, but ethylene oxide appears safe with most, as are several solutions.
Examples are based on acrylic plastics, with which the author is most familiar, but the principles apply to most rigid polymers. Sources of additional detailed technical information are suggested.
Paper ID: STP43776S