BS ISO 19935‑2:2020 Plastics — Temperature modulated DSC Part 2: Measurement of specific heat capacity c p. 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 472, ISO 11357‑1, ISO 19935‑1 and ISO 80000‑5 apply. ISO and IEC maintain terminological databases for use in standardization at the following addresses: — ISO Online browsing platform: available at https://www.iso.org/obp — IEC Electropedia: available at http://www.electropedia.org/ 4 Symbols and abbreviated terms 4.1 Temperature modulation, T(t) According to ISO 19935‑1. 4.2 Scanning rate According to ISO 19935‑1. 4.3 Heat flow rate, Φ(t) According to ISO 19935‑1. b) Depending on the relation of the underlying scanning rate fib to the amplitude of sample temperature profile TAW (where w the angular frequency) four cases of scanning rates are distinguished. 1) Quasi—isothermal mode, flu = 0. If flu = 0, heat capacity can he measured as function of time, e.g. during chemical reactions like curing or during crystallization. All other calorimetric methods measure heat capacity as function of temperature only. 2) For other modes, such as TAW > fib1 TACO <flu, and TACO = fib, refer to ISO 19935-1. c) Any mode of temperature modulation specified in ISO 19935-1 can be used. 7 Calibration 7.1 General According to ISO 19935-1. 7.2 Calibration of modulation amplitude According to ISO 19935-1. 7.3 Calibration of phase According to ISO 19935-1. 8 Procedure 8.1 General The procedures of temperature modulated DSC (setting up the apparatus, loading the specimen into the crucibles, insertion of crucibles into the instrument, performing measurements, and removal of crucibles) shall be in accordance with ISO 11357-1. The experimental conditions specified for temperature modulated DSC (for example, amplitude of the modulated heat flow rate, amplitude of modulated temperature, and the frequency of the modulation superimposed on the underlying rate) to be used depend on the magnitude of the specific heat capacity to be determined. 10 Test report The test report shall include the following information: a) a reference to this document, i.e. ISO 19935‑2:2020; b) type and complete identification of specimen; c) type (heat flux or power compensated), manufacturer and model of DSC instrument used; d) material, type and mass of crucible used; e) type, purity and heat flow rate of purge gas used; f) type of calibration procedure (simplified or extended), calibration materials used, including source, mass and other properties important for calibration; g) details of sampling, preparation of...
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