A Preliminary Investigation of the Microstructure and Mechanical Properties of Porous Polymers,
Abstract
Porous polymers exhibit complex microstructures which affect their mechanical and physical properties. Pores in the microstructure are the result of the addition of Expancel(TM) polymer microspheres, and potentially by gas entrained during mixing operations. The entrained gas pores can form long strings and sheets which may act as defects in the structure. A combination of direct observation and finite element modeling has shown that accounting for the stiffening effect of the microspheres is important, and that strain localization occurs due to microstructural heterogeneity and interactions generated by the large gas pores. Permanent creep deformations can be imparted to the material in relatively short times, perhaps due to the localizations previously noted. Initial investigations into wave propagation and nondestructive evaluation by microwave dielectrometry were successful.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 28, 1997
- Accession Number
- ADA321890
Entities
People
- D. P. Harvey Ii
- N. K. Batra
- P. Matic
- R. K. Everett
- R. S. Schechter
Organizations
- United States Naval Research Laboratory