Accession Number:

ADA172047

Title:

Time-Dependent Response and Fracture of Cross-Linked Polymer.

Descriptive Note:

Final rept. Jan 83-Dec 86,

Corporate Author:

AKRON UNIV OH INST OF POLYMER SCIENCE

Personal Author(s):

• Kelley,F. N.
• Morton,M.
• Plazek,D.

Report Date:

1986-12-01

Pagination or Media Count:

36.0

Abstract:

This study was concerned with the synthesis, preparation and characterization of cross-linked polymers, and their time-dependent fracture behavior. Emphasis was given to well-defined polymer network structures of two types 1 end-linked terminally functional liquid polymers having nearly uniform or deliberately distributed initial chain lengths, and 2 model glassy networks in which the network topology was varied with respect to chain length per cross-link, and network defects such as dangling ends and soluble fraction. Also, a model rubber-toughened resin was developed by dispersing well-characterized rubber particles, made separately from the matrix, into an epoxy matrix resin. Thermally stable polyn-butyl acrylate based particles, cross-linked and functionalized, had their size and size distribution controlled by the polymerization method. Differences were observed in the fracture energies of the individual matrix resins containing different rubber particle sizes and particle reactivity. The model composite fracture energies display maxima when plotted against weight percent particles. A theoretical model for rubber toughening by Kunz-Douglass, et al. was examined but this model was shown to be inadequate in predicting the composite fracture energy dependence on constituent properties, as well as in predicting the correct functional form.

Descriptors:

• *POLYMERS
• *EPOXY RESINS
• *ACRYLATES
• *ISOPRENE
• REPRINTS
• LIQUIDS
• SYNTHESIS(CHEMISTRY)
• CROSSLINKING(CHEMISTRY)
• HYDROXYL RADICALS

Subject Categories:

• Polymer Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE