1.1, the clean aluminum foil into the oven at 100 ℃ oven bake 1 hour;
1.2, the aluminum foil into the dryer, the cooling at room temperature to the aluminum foil weight stability;
1.3, accurately weighed aluminum foil disc and record the weight of M1;
1.4, take the silica gel sample about 10 grams and cut into about 1cm2 size into the aluminum foil plate;
1.5, the sample together with the aluminum foil into the dryer;
(This step is very important to prevent moisture contact with the sample)
◆ The time of this step depends on the indoor humidity, when the weight of the sample for two consecutive weighing the same time, determine the sample is dry
◆ Recommended sample drying time of not less than 12 hours
1.6, accurate weighing aluminum plate + sample weight M2;
1.7, the sample curing process: the sample and the aluminum foil tray together into the oven at 200 ℃ constant temperature 4 hours;
1.8, the vulcanized samples with aluminum foil tray together into the dryer, at room temperature for cooling at least 3 small
Until no change in weight stability;
1.9, accurately weighed and cooled by drying and drying aluminum foil plate + sample and record the weight of M3;
1.10, the formula for calculating the percentage of VOM content is:
% VOM = [(M2-M1) – (M3-M1)] / (M2-M1) x100