Accession Number : AD0729821

Title :   Dynamic Tangent Moduli of Polyvinyl Chloride Subjected to Large Strains.

Descriptive Note : Technical rept.,

Corporate Author : BROWN UNIV PROVIDENCE R I DIV OF APPLIED MATHEMATICS

Personal Author(s) : Reilly,Bernard J. , Jr

Report Date : APR 1971

Pagination or Media Count : 48

Abstract : The data presented describes the changes in the linear dynamic viscoelastic properties of PVC when it has been subjected to large one-dimensional strains. Dynamic tests were carried out on specimens which had undergone large quasistatic deformations in conditions of both creep and relaxation. At various times during the tests, small oscillatory deformations were superimposed on the large deformations. By measuring the resonant frequencies and decay curves, the values of the complex shear modulus and complex Young's modulus were determined. The large axial deformations were produced by a machine made specifically for these tests. The small oscillatory deformations were produced by a coil-magnet system arranged so that either lateral or torsional vibrations could be set up. The detection and measurement of the vibrations was also carried out by a coil-magnet system. An oscilloscope was employed to display the detected signals. The resonant frequency could be found and a decay-curve picture could be recorded from the oscilloscope traces. The shear modulus was determined by data from the torsional vibrations, while the Young's modulus was extracted from data with lateral vibrations. (Author-PL)

Descriptors :   (*POLYVINYL CHLORIDE, VISCOELASTICITY), (*POLYMERS, VISCOELASTICITY), STRAIN(MECHANICS), DEFORMATION, MODULUS OF ELASTICITY, CREEP, VIBRATION, TEST METHODS, STRESSES

Subject Categories : Plastics
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE