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Premixed commercial polysulfide aircraft sealants stored at -20, -30, and -40 °C were tested for conformity to cure rate, application time, tack-free time, and peel strength requirements. With manganese dioxide cured products no significant change in hardness or peel strength occurred after prolonged storage at -20 °C and below; a minor decline in peel strength was observed with a dichromate-cured sealant. Application properties were maintained for extended periods, and at -40 °C tests terminated only through consumption of samples after storage times (7-16 weeks) that far exceeded published recommendations. Batch variations and stricter observation of class requirements would influence storage times, but at -40 °C even materials with little margin in application life rating could be safely stored in a premixed state for at least 10 weeks. Both Aand B-class sealants were able to be stored in this manner provided their application lives were >2 h.

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