Polyurethane-foam-component incompatibilities. [As access deterrent]
Access deterrent foams are generated by mixing separately stored and pressurized isocyanate and polyol components upon demand. This specially designed rigid polyurethane foam system must survive ambient storage and still give acceptable foams. The polyol component, a polypropylene oxide diol adduct of phosphoric acid, in the presence of moisture apparently hydrolyzes to phosphoric acid which attacks the container and alters the foaming action. The phosphate ester adduct's fire-retardant characteristics were sacrificed in favor of a superior aging polyol component. Thus, a second foam formulation which did not contain any phosphoric acid adducts while exhibiting virtually identical foaming properties was aged under accelerated conditions. These conditions consisted of aging at room temperature, 60 and 71/sup 0/C, whereby lifetime predictions could be made by Arrhenius modeling. Specifically, the amine equivalent was followed in the isocyanate component while acid number and hydroxyl equivalent were determined in the polyol component. Interestingly, the isocyanate behaved in a predictable manner; however, again problems were encountered with the polyol component. A reaction between the polyol and the blowing agent, Freon 11, was found to give high acid content abruptly following a temperature dependent initiation period. Attempts to add inhibitors to lengthen this initiation period failed. These unsolved incompatibility problems have resulted in a foam system of uncertain quality and unknown lifetime. A third foam system is currently under investigation. 4 figures, 5 tables.
- Research Organization:
- Sandia National Labs., Albuquerque, NM (USA)
- DOE Contract Number:
- AC04-76DP00789
- OSTI ID:
- 7049618
- Report Number(s):
- SAND-82-1655; CONF-821038-1; ON: DE82022162
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
Inspection
& Accountability-- Technical Aspects
98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL PROTECTION
AGING
ALLOYS
CHEMICAL REACTIONS
COLLOIDS
COMPATIBILITY
CORROSION
DISPERSIONS
FOAMS
FREONS
HALOGENATED ALIPHATIC HYDROCARBONS
HYDROGEN COMPOUNDS
INORGANIC ACIDS
IRON ALLOYS
IRON BASE ALLOYS
MATERIALS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC POLYMERS
PETROCHEMICALS
PETROLEUM PRODUCTS
PHOSPHORIC ACID
PHYSICAL PROTECTION DEVICES
PLASTICS
POLYAMIDES
POLYMERS
POLYURETHANES
STABILITY
STEELS
STORAGE
SYNTHETIC MATERIALS