1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 13145:2012Rubber Determination ofviscosity and stress relaxationusing a rotorless sealed shearrheometerBS ISO 13145:2012 BRITISH STANDARDNational forewordThis British Stan
2、dard is the UK implementation of ISO 13145:2012. The UK participation in its preparation was entrusted to TechnicalCommittee PRI/22, Physical testing of rubber.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to inclu
3、de all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2012.Published by BSI Standards Limited 2012ISBN 978 0 580 68203 2 ICS 83.060 Compliance with a British Standard cannot confer immunity from legal obligations.This Brit
4、ish Standard was published under the authority of the Standards Policy and Strategy Committee on 30 November 2012.Amendments issued since publicationDate T e x t a f f e c t e dBS ISO 13145:2012 ISO 2012Rubber Determination of viscosity and stress relaxation using a rotorless sealed shear rheometerC
5、aoutchouc Dtermination de la viscosit et de la relaxation de contrainte au moyen dun rhomtre cisaillement sans rotor tancheINTERNATIONAL STANDARDISO 13145First edition2012-09-15Reference number ISO 13145:2012(E)BS ISO 13145:2012ISO 13145:2012(E)ii ISO 2012 All rights reservedCOPYRIGHT PROTECTED DOCU
6、MENT ISO 2012All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body
7、in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copyrightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 13145:2012ISO 13145:2012(E) ISO 2012 All rights reserved iiiContents PageForeword ivIntroduction v1 Sco
8、pe . 12 Normative references 13 Terms and definitions . 14 Principle 25 Apparatus . 35.1 General . 35.2 Die cavity 35.3 Die closure 35.4 Movement 35.5 Heating and temperature control . 45.6 Torque-measuring system 46 Calibration 67 Test piece 67.1 Preparation of the test piece . 67.2 Protective film
9、s . 68 Temperature . 69 Procedure. 79.1 Testing sequence . 79.2 Preparation for the test . 79.3 Rheometer loading 710 Reporting of results . 710.1 Examples of reporting results 710.2 Basic expression of results . 710.3 Additional results . 810.4 Stress relaxation test results . 811 Precision . 812 T
10、est report . 8Annex A (normative) Calibration schedule 10Annex B (informative) Precision data 12Bibliography .14BS ISO 13145:2012 ISO 13145:2012(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of
11、preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental,
12、 in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.The main tas
13、k of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.Attention
14、 is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.ISO 13145 was prepared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 2, Testing
15、 and analysis.iv ISO 2012 All rights reservedBS ISO 13145:2012ISO 13145:2012(E)IntroductionThe rheological properties of rubbers are related to their structural characteristics and will influence the behaviour of the rubber during processing and the performance of the final product.For these reasons
16、, the industrial environment requires instruments that can quickly and easily evaluate the rheological properties.As a consequence, this standard test method was formulated using a rotorless sealed shear rheometer for rheological evaluation under defined conditions.This test could be an alternative
17、to the Mooney viscometer, still used as standard in many parts of the rubber industry to measure Mooney viscosity (in accordance with ISO 289-1). The defined conditions have been selected to provide a shear rate range similar to that used for Mooney viscosity and a good repeatability level.This new
18、test procedure should be performed over a short time and preferably in the automatic mode to optimize test efficiency. ISO 2012 All rights reserved vBS ISO 13145:2012 ISO 13145:2012(E)BS ISO 13145:2012Rubber Determination of viscosity and stress relaxation using a rotorless sealed shear rheometerWAR
19、NING Persons using this International Standard should be familiar with normal laboratory practice. This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to e
20、nsure compliance with any national regulatory conditions.1 ScopeThis International Standard describes a method for the determination of the viscosity and stress relaxation of raw or compounded rubber under specified conditions.The viscosity determination consists of a constant strain, temperature an
21、d frequency test in which the elastic and the loss components of the complex shear modulus can be determined.The determination of stress relaxation consists of a constant static strain and temperature test in which the torque decrease can be determined.2 Normative referencesThe following referenced
22、documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 1382, Rubber VocabularyISO 18899:2004, Rubber Guide to the calibration
23、of test equipment3 Terms and definitionsFor the purpose of this document, the terms and definitions given in ISO 1382 and the following apply.3.1rotorless sealed shear rheometerdevice consisting of two dies forming a temperature-controlled cavity, one of which is moved relative to the other to apply
24、 a stress or strain to the test piece3.2sinusoidal strain(t)strain produced by the oscillation of the die constituting the test cavityNOTE It is given by the expression (t) = 0sin(t), where 0is the maximum amplitude of the applied strain.3.3loss anglephase angle between the stress and the strainNOTE
25、 This is a measure of the presence and extent of viscous behaviour in a material. For viscoelastic materials, the phase angle can assume a value between 0 and 90. 90 is an ideal Newtonian liquid.INTERNATIONAL STANDARD ISO 13145:2012(E) ISO 2012 All rights reserved 1BS ISO 13145:2012ISO 13145:2012(E)
26、3.4complex torqueS*torque measured by the machine due to application of sinusoidal strainNOTE The complex torque is a vector which can be represented by a complex number, viz S* = S + iS”.3.5elastic torqueScomponent of torque that is in phase with the imposed sinusoidal strainNOTE It is given by the
27、 equation S = |S*|cos.3.6loss torqueS”component of torque that is in quadrature with the imposed sinusoidal strainNOTE It is given by the equation S” = |S*|sin.3.7complex shear modulusG*ratio of the shear stress to the shear strain, where each is a vector which can be represented by a complex number
28、NOTE 1 It is given by the equation G* = G + iG”.NOTE 2 The complex shear modulus is determined by dividing the complex torque S* by the applied strain and multiplying by a geometric factor related to the cavity shape.3.8elastic shear modulusGcomponent of the applied shear stress that is in phase wit
29、h the shear strain, divided by the strainNOTE It is given by the equation G = |G*|cos.3.9loss shear modulusG”component of the applied shear stress which is in quadrature with the shear strain, divided by the strainNOTE It is given by the equation G” = |G*|sin.3.10tangent of the loss angletanratio of
30、 the loss modulus to the elastic modulus4 PrincipleThe torque generated in a test piece contained in a heated sealed cavity formed by two dies, one of which can be oscillated through a small amplitude, is measured.2 ISO 2012 All rights reservedBS ISO 13145:2012ISO 13145:2012(E)5 Apparatus5.1 General
31、A rotorless sealed shear rheometer consists of two dies that are heated and closed, under a specified force, to form a sealed test cavity that contains the test piece. One of the dies oscillates, and a measuring system records the torque required to produce the relative movement. The elastic torque
32、S and the loss torque S” produced in a test piece by the strain due to the oscillation of the die can be measured at specified conditions of temperature, frequency and amplitude.The general arrangement of a rotorless sealed shear rheometer is shown in Figure 1, including typical machine dimensions.5
33、.2 Die cavityThe dies shall be manufactured from a stiff material. The surface of the dies shall be treated to minimize the effect of test piece contamination if protective or carrying film are not used and shall be hard enough to prevent wear. A minimum Rockwell hardness of 50 HRC, or equivalent, i
34、s recommended. The tolerances necessary on the dimensions of the dies depend on the particular design, but as a general guide the dimensions of the cavity should be controlled to 0,2 %.The top and bottom surfaces of the cavity shall have a pattern of grooves of dimensions sufficient to prevent slipp
35、age of the rubber test piece.Holes shall be provided in both the upper and lower dies to accommodate temperature sensors. The positions of the sensors relative to the cavity shall be controlled to ensure a reproducible response.A seal of suitable low, constant friction shall be provided to prevent m
36、aterial leaking from the cavity.Suitable means shall be employed, by design of the dies or otherwise, to apply pressure to the test piece throughout the test to minimize slippage between the disc and the rubber.5.3 Die closureThe dies shall be closed and held closed during the test by, for example,
37、a pneumatic cylinder.The closing force required depends on the clearance area; as a general guide, a minimum of 7 kN is recommended. The contact of the die cavity edges shall be such as to form a perfectly sealed cavity.5.4 MovementThe moving part in a rotorless instrument is one of the dies. The di
38、es are usually biconical to produce a substantially uniform shear rate, and this shape is useful to make the test piece loading and unloading stages easier. The drive linkage shall be sufficiently stiff to prevent significant deformation.A torsional oscillating movement shall be applied to one of th
39、e dies (typically the lower in the cavity) by means of a motor.The frequency of oscillation can be varied according to the instrument specification, but in this International Standard a single frequency is selected.The oscillation amplitude may be varied according to the deformation required. The ma
40、ximum amplitude of the applied strain y0is calculated considering the oscillation angle used in the test and the die geometry (conical). It is given by the expressiony0= / where is the characteristic angle of the conical die. ISO 2012 All rights reserved 3BS ISO 13145:2012ISO 13145:2012(E)Generally,
41、 greater sensitivity can be obtained with larger amplitudes, but the amplitude that can be used in practice is restricted by the possibility of slippage between the test piece and the die surface.5.5 Heating and temperature controlThe heating and temperature control system shall be capable of produc
42、ing a reproducible and evenly distributed temperature in the dies and shall permit fast and reproducible temperature recovery after insertion of the test piece.The temperature-measuring system shall enable the temperature to be measured to a resolution of 0,1 C over the range from 60 C to 200 C. The
43、 temperature controllers shall enable the temperature of the dies to be controlled to an accuracy of 0,3 C in the steady state.5.6 Torque-measuring systemA suitable transducer shall be provided which is capable of measuring the force or torque with an accuracy of 1 %.A recorder shall be provided to
44、continuously monitor force or torque. It shall have a response time for full-scale deflection equal to or below 1 s.Dimensions in millimetres1921106634857a) Measurement principle4 ISO 2012 All rights reservedBS ISO 13145:2012ISO 13145:2012(E)4011b) Die (upper and lower)c) Test pieceKey1 heater 7 tor
45、que-measuring system2 lower die 8 test piece3 lower seal plate 9 seals4 upper seal plate 10 oscillating-drive system5 upper die 11 grooves6 temperature sensorFigure 1 Typical rotorless sealed shear rheometer with biconical-die structure ISO 2012 All rights reserved 5BS ISO 13145:2012ISO 13145:2012(E
46、)6 CalibrationThe test apparatus shall be calibrated in accordance with the schedule given in Annex A.Calibration of rheometers shall be carried out in accordance with the manufacturers instructions. The force or torque shall be determined at several points over the range(s) used but, additionally,
47、it can be useful to have provision to make in-use checks.Stable rubber reference compounds can also be tested periodically to check for consistent performance.7 Test piece7.1 Preparation of the test pieceThe test piece shall be homogeneous and, as far as possible, free from trapped air.The pertinent
48、 volume shall be determined by appropriate tests, and test pieces of equal volume shall be used to obtain reproducible results. This volume shall be slightly larger than the die cavity volume (typically 130 % to 150 % larger) so that a small amount of material is extruded between all edges of the di
49、es when they are closed.This volume corresponds to 5 cm3and 6 cm3for the typical sealed rheometer shown in Figure 1.The test piece shall be punched out by an appropriate device which ensures the production of test pieces of constant volume.For best repeatability, the mass of the test piece shall be controlled to within 0,5 g to obtain the required volume.Conditioning the test piece at 23 C 5 C for a minimum of 3 h before testing is recommended.7.2 Protective filmsOne or more layers of protec
