BS ISO 2303:2019 pdf download – Isoprene rubber (IR) — Non-oil-extended, solution- polymerized types — Evaluation procedures

BS ISO 2303-2019 pdf download – Isoprene rubber (IR) — Non-oil-extended, solution- polymerized types — Evaluation procedures 7 Evaluation of vulcanization characteristics by a curemeter test WARNING — Formation of nitrosamines is possible during the cure. 7.1 Using an oscillating-disc curemeter Measure the following standard test parameters: M L , M H at defined time, t s1 , t′ c (50) and t ′c (90) in accordance with ISO 6502-2, using the following test conditions: — oscillation frequency: 1,7 Hz (100 cycles per minute); — amplitude of oscillation: 1° of arc; — selectivity: to be chosen to give at least 75 % of full-scale deflection at M H (note that with some rubbers, 75 % might not be attainable); — die temperature: 160 °C ± 0,3 °C; — pre-heat time: none. 7.2 Using a rotorless curemeter Measure the following standard test parameters: F L , F H at defined time, t′ c( 50) and t′ c (90) in accordance with ISO 6502-1, using the following test conditions: — oscillation frequency: 1,7 Hz (100 cycles per minute); — amplitude of oscillation: 0,5° of arc; — selectivity: to be chosen to give at least 75 % of full-scale deflection at F H (note that with some rubbers, 75 % might not be attainable); — die temperature: 160 °C ± 0,3 °C; — pre-heat time: none. 8 Evaluation of tensile stress-strain properties of vulcanized test mixes Vulcanize sheets at 135 °C for three periods chosen from a cure series of 20 min, 30 min, 40 min and 60 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 at a standard temperature and, if possible, a standard humidity, as defined in ISO 23529. Measure the stress-strain properties in accordance with ISO 37. 9 Precision See Annex A for the information on precision data for both mill mixer and laboratory internal mixer. See Annex B for the information on additional precision data for natural rubber. 10 Test report The test report shall include the following information: a) a reference to this document, i.e. ISO 2303:2019; b) all details necessary for the identification of the sample; c) the time and temperature conditions used for the Mooney viscosity determination, and whether a massing process was used; d) the method used for the volatile-matter content...