Accession Number:

ADA426907

Title:

Modeling Decomposition of Unconfined Rigid Polyurethane Foam

Descriptive Note:

Corporate Author:

SANDIA NATIONAL LABS ALBUQUERQUE NM

Report Date:

1999-11-01

Pagination or Media Count:

74.0

Abstract:

The decomposition of unconfined rigid polyurethane foam has been modeled by a kinetic bond-breaking scheme describing degradation of a primary polymer and formation of a thermally stable secondary polymer. The bond-breaking scheme is resolved using percolation theory to describe evolving polymer fragments. The polymer fragments vaporize according to individual vapor pressures. Kinetic parameters for the model were obtained from Thermal Gravimetric Analysis TGA. The chemical structure of the foam was determined from the preparation techniques and ingredients used to synthesize the foam. Scale-up effects were investigated by simulating the response of an incident heat flux of 25 Wsq cm on a partially confined 8.8-cm diameter by 15-cm long right circular cylinder of foam which contained an encapsulated component. Predictions of center, midradial, and component temperatures, as well as regression of the foam surface, were in agreement with measurements using thermocouples and X-ray imaging.

Subject Categories:

  • Miscellaneous Materials

Distribution Statement:

APPROVED FOR PUBLIC RELEASE