The dynamic mechanical method for the characterization of solid composite polymers

Abstract

Abstract Information and parameters obtainable from the dynamic mechanical thermal analysis test method are defined. The sensitivity of the technique in detecting the presence of separate phases is emphasized. The Polymer Laboratories DMTA instrumentation is briefly described and its various modes of operation, such as frequency multiplexing, discussed. The theory of the mechanical response of two phase systems is presented via the Takayanagi model approach. Series and parallel coupling constants are derived for a few systems as examples of the definition of phase morphology. Examples are given of the results for ethylene‐propylene random copolymer, block copolymer elastomers, rubber toughened poly(styrene), carbon fiber reinforced expoxies with different orientations of fiber, and carbon black filled rubbers. The engineering properties of composites are available directly from the PL‐DMTA, which provides sensitive detection of non‐linear mechanical behavior, frequently found in multi‐phase polymer systems.