The Fracture of Thermosetting Resins After Exposure to Water.
Abstract
This report summarizes the conclusions from a study of the effect of molecular weight and molecular weight distribution on the hydrolytic stability and the mechanical properties of polyester resins immersed in water. Comparison of fractionated ones, with and without vacuum stripping, leads to the conclusion that water absorption is extremely dependent on the presence of traces of low molecular weight, water-coluble substances. The extent of change of compressive modulus, and certain other mechanical properties, reflected water absorption behaviour, but fracture toughness was not very dependent on water uptake, at least until the stage of irreversible damage was reached. Chain lengths below Mn = 1000 resulted in inferior initial fracture toughness and inferior hydrolytic behavior. Related studies of the viscoelastic characteristics of the unimmersed resins are outlined. A brittle-ductile transition was observed, and changes in fracture toughness were found, at 28 deg C.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1982
- Accession Number
- ADA122063
Entities
People
- David T. Ho
- Geoffrey Pritchard
- J. S. Ghotra
- R. G. Rose
- W. E. Douglas