Abstract
One kind of hardener, four kinds of polyepoxide diluents, and nine kinds of liquid resins were used in the present study. As the result of experiments on the temperature dependence of viscosity using liquid epoxy resins in the temperature range of +19°to -16°C, it was found that all materials should be modified when used under conditions below freezing point.
The viscosity of 144 kinds of liquid resins prepared by adding diluents to liquid epoxy resins at the ratio of 12 to 48phr was measured at -6°C. Using 65 kinds of liquid resins with viscosity under 50000cps, the bond strength by tension was measured according to JIS K 6849 at -6°C.
The bond strength of 51 kinds of liquid resins showed values higher than 150kg/cm2. Eight kinds of liquid resins were selected from these and used in the subsequent experiments.
The viscosity and gel time of equivalent mixtures of liquid resins and hardeners were measured. All mixtures showed viscosity under 50000cps.
Strength tests of epoxy resin mortars subjected to 8 days or 6 months curing, and 6 months cured jointing of successive pours to cement mortar were conducted. The strength of test specimens of 6 months curing generally was low in the case when the binders gave negative or negligible heat generation during gelation.
The best results can be obtained in the case of epoxy resin mortars using liquid resins which contained diglycidyl ether of resorcinol as the main ingredient.
