BS ISO 4659:2020 pdf free.Styrene-butadiene rubber [carbon black or carbon black and oil masterbatches)一Evaluation procedure.
BS ISO 4659 Method B一Single stage mixing using a laboratory internal mixer For laboratory internal mixers having 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 °C 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 starting temperature so that this condition is met In the following procedure, compounding materials other than masterbatch, 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:一a mortar and pestle;-a double- cone mixer (mix for 10 min with the intensifier bar urning);
-a blender (mix for five periods of3 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.Vulcanize sheets at 145 °C for 25 min, 35 min, and 50 min. Alternatively, vulcanize sheets at 150。C for 20 min, 30 min, and 50 min. The three periods of cure shall be chosen to cover the undercure, optimum cure, and overcure of the material under test.Condition the vulcanized sheets for 16 h to 96 h, if possible at standard temperature and humidity as defined in ISO 23529.Measure the stress-strain properties in accordance with ISO 37.BS ISO 4659 pdf download.