BS ISO 2302:2014 pdf free

BS ISO 2302:2014 pdf free.Isobutene-isoprene rubber (IIR)一Evaluation procedure
For laboratory internal mixers having a nominal capacities of 65 cm3 to about 2 000 cm3, the batch mass shall be equal to the nominal mixer capacity, in cubic centimetres, multiplied by the density of the compound. For each batch mixed, the laboratory internal mixer conditions shall be the same during
the preparation of a series of identical mixes. At the beginning of each series of test mixes, a machine-conditioning batch shall be mixed using the same formulation as the mixes under test. The laboratory internal mixer shall be allowed to cool down to 60℃ between the end of one test batch and the start of
the next. The temperature control conditions shall not be altered during the mixing of a series of test batches.
The mixing technique shall be such as to obtain a good dispersion of all the ingredients.
The temperature of the batch discharged on completion of mixing shall not exceed 120 °C. If necessary, adjust the batch mass or the mixer head starting temperature so that this condition is met
In the fllowing procedure, compounding materials other than rubber and carbon black, may be added to the batch more precisely and with greater ease if they are previously blended together in the proportions required by the formulation. Such blends may be made using one of the following:
– a mortar and pestle;
– a double-cone mixer (mix for 10 min with the intensifier bar turning);
– a blender (mix for five periods of 3 s each, scraping the inside of the blender to dislodge material stuck to the sides after each 3 s period) [a “Waring”-type blender has been found suitable for this method).
CAUTION一If the mixing periods are longer than 3 s, the stearic acid may melt, thus preventing good dispersion.
The mixing technique shall be such as to obtain a good dispersion of all the ingredients.
The temperature of the batch discharged on completion of mixing shall be between 150 °C and 170 °C  If necessary, adjust the batch mass or the mixer head starting temperature so that this condition is met.
During final mixing, a good rolling bank at the nip of the rolls shall be maintained. If this is not obtained with the nip setting specified, small adjustments to the mill openings may be necessary.BS ISO 2302 pdf download.