A Rational Approach to the Design and Synthesis of Tough Glassy Polymers

Abstract

In this work we have designed and synthesized high Tg yet ductile polymers using a building block approach. In this approach functional molecular groups that provide high Tg alternate with molecular linkages that provide mobility. Specifically molecular mobility is provided by in-chain cyclohexylene units. The existence of mobility is verified by dynamic mechanical studies, and supported by positronium annihilation studies. We discovered an unusual behavior in the three series of polymers studied wherein the higher mobility is found to be accompanied by higher Tg yet lower modulus. This observation is explained in terms of the increase in the persistence length of the polymer with increasing cyclohexylene ester content. The greater persistence length improves packing, resulting in higher Tg, while the mobility reduces interchain interaction, thus reducing modulus. This work suggests that the building block approach may allow scientists to synthesize polymers with various physical functions yet with ductility.

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Document Details

Document Type
Technical Report
Publication Date
Mar 20, 2001
Accession Number
ADA388214

Entities

People

  • Albert F. Yee

Organizations

  • University of Michigan

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Air Force
  • Dacron
  • Ductility
  • Engineering
  • Frequency
  • Glass Transition Temperature
  • Mechanical Properties
  • Mechanics
  • Modulus Of Elasticity
  • Molecular Dynamics
  • Phase Transformations
  • Physical Properties
  • Stiffness
  • Stresses
  • Thermal Expansion
  • Transition Temperature
  • Transitions

Readers

  • Computational Modeling and Simulation
  • Polymer Science and Technology