1、UDC 678.074 : 620.1 : 532.137 DEUTSCHE NORMEN November 1976 TESTING WITH THE rb0NEY SHEARING DISK VISCOMETER Determining the Scorching Behaviour Testing of Rubber and Elastomers 53 523 Part 4 Prfung von Kautschuk und Elastomeren; Prfung mit dem Scherscheiben-Visko- simeter nach Mooney; Bestimmung de
2、s Anvulkanisationsverhaltens For connection with the Standard IS0 667 published by the International Organization for Standardization (ISO), see Explanations in DIN 53 523 Part 1. 1 Purpose This Standard describes the method for determining the scorching behaviour of unvulcanized mixtures based on n
3、atural and synthetic rubber using the shearing disk viscometer. No te : IS0 667-1975 calls this method a method for determining the rate of cure. However, the method is generally only suitable for determining the vulcanization behaviour in the starting range. 2 Definitions 2.1 Viscosityminiaum M . i
4、s the reading of the shearing disk viscometer in the torque minimum (expressed in Mooney units)/time curve (see diagram). min 2.2 Scorching time t5 is the time in minutes from the start of the measurement (see Section 4) to a Mooney viscosity rise of 5 Mooney units above the viscosity minimum. It is
5、 called the scorching time (see diagram). 2.3 Scorching time t35 is the time in minutes from the start of the measurement (see Section 4) to a Mooney viscosity rise of 35 Mooney units over the viscosity minimum (see diagram) - 2.4 Rise time At is the time difference ts5 - t5. Note : The definitions
6、used here are not identical with those of -3 529 Part 1 and 2. In this Standard, the definitions are explained in greater detail than in ISO/R 667 and the latter does not refer to the scorching time in conjunction with t5. When using the small rotor (see DIN 53 523 Part 2) tg is determined instead o
7、f t5 and t18 instead of ts5 in accordance with ASTM D 1646-68 and consequently bt is defined as the time difference t18t3. IS0 667 and consequently also this Standard does not make this distinction in the testing methods and their evaluation. For Explanations, see DIN 53 523 Part 1. Continued on pag
8、es 2 and 3 DIN 53523 Teil 4 engl. Preisgr. 4 Vem.-Nr. O1 O4 Sole sale rights of German Standards (DIN-Normen) are with Beuth Verlag GmbH, Berlin 30 05.81 Page 2 DIN 53 523 Part 4 -1- Time in minutes- Graphical evaluation of the measuring results 3 Sample preparation and specimens 3.1 Sample preparat
9、ion See DIN 53 523 Part 1, November 1976 edition, Section 2.2.2 3.2 Specimens See DIN 53 523 Part 3, November 1976 edition, Section 3.3 4 Procedure The test is performed in accordance with DIN 53 523 Part 3, November 1976 edition, Section 5. The test chamber temperature is adjusted to the temperatur
10、e agreed for the mixture under investigation, to within a permitted deviation of i 0.5 OC, see DIN 53 523 Part 2, November 1976 edition, Section 4.3 (it is not possible to give a generally binding temperature for all mixtures). The test time is calculated from the time at which the chamber is closed
11、. The test continues until the Mooney viscosity has risen by at least 40 units above the minimum viscosity (see Section 2.1). 5 Test reDort Designaticn of the samples Test temperature Rotor Scorching time t5 in min If required: Scorching time t35 and rise time At = t35-t5 in min Deviations from this
12、 Standard Test date DIN 53 523 Part 4 Page 3 Further Standards DIN 53 523 Part 1 Testing of rubber and elastomers; testing with the Mooney shearing disk viscometer; preparation of samples DIN 53 523 Part 2 Testing of rubber and elastomers; testing with the Mooney shearing disk viscometer; equipment requirements DIN 53 523 Part 3 Testing of rubber and elastomers; testing with the Mooney shearing disk viscometer; determining the Mooney viscosity
