1、Designation:D105392a(Reapproved 2012)Standard Test Methods forRubber PropertyStiffening at Low Temperatures:FlexiblePolymers and Coated Fabrics1This standard is issued under the fixed designation D1053;the number immediately following the designation indicates the year oforiginal adoption or,in the
2、case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 These tes
3、t methods describe the use of a torsionalapparatus for measuring the relative low temperature stiffeningof flexible polymeric materials and fabrics coated therewith.Aroutine inspection and acceptance procedure,to be used as apass-fail test at a specified temperature,is also described.1.2 These test
4、methods yield comparative data to assess thelow temperature performance of flexible polymers and fabricscoated therewith.1.3 The values stated in SI units are to be regarded asstandard.The values given in parentheses are for informationonly.1.4 This standard does not purport to address all of thesaf
5、ety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D832 Practice for Rubber Conditioni
6、ng For Low Tempera-ture TestingD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustries3.Summary of Test Method3.1 Test Method A describes the measurement,at lowtemperatures,of the stiffening of flexible polymers.3.2 Test Method B descri
7、bes the measurement,at lowtemperatures,of the stiffening of fabrics coated with flexiblepolymers.3.3 In these test methods,a specimen of flexible polymer orfabric coated with flexible polymer is secured and connected inseries to a wire of known torsional constant;the other end ofthe wire is fastened
8、 to a torsion head to impart a twist to thewire.The specimen is immersed in a chamber filled with a heattransfer medium at a specified uniform subnormal temperature.The torsion head is then twisted 180 and in turn twists thespecimen by an amount(less than 180)that is dependent onspecimen compliance
9、or inverse stiffness.After a specifiedelapsed time,the amount of specimen twist is measured with amounted protractor.The angle of twist,which is inverselyrelated to the stiffness,is plotted versus the specified tempera-ture.The temperature is then systematically increased inprescribed increments and
10、 the measurements repeated at eachtemperature,yielding a twist or inverse stiffness versus tem-perature profile for the test specimen.The torsional modulus ofthe specimen at any temperature is proportional to the quantity(180-twist)/twist.4.Significance and Use4.1 These test methods may be used to d
11、etermine thesubnormal temperature stiffening of flexible polymers or fab-rics coated with flexible polymers.Temperatures at which thelow temperature modulus is a specified multiple or ratio of themodulus at room temperature are interpolated from the twistversus temperature curve.These specified rati
12、os of low-temperature modulus to room-temperature modulus are calledrelative moduli.These temperatures at the relative moduliencompass the transition region between the glassy and rub-bery states of the materials tested.1These test methods are under the jurisdiction of ASTM Committee D11 onRubber an
13、d are the direct responsibility of Subcommittee D11.10 on PhysicalTesting.Current edition approved Dec.1,2012.Published February 2013.Originallyapproved in 1943.Last previous edition approved in 2007 as D1053 92a(2007).DOI:10.1520/D1053-92AR12.2For referenced ASTM standards,visit the ASTM website,ww
14、w.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.2 These te
15、st methods offer only a general guide to stiffnesscharacterization as service conditions of experimental materi-als may differ greatly from the test conditions.5.Apparatus5.1 Torsion Apparatus3The torsion apparatus(Fig.1)shall consist of a torsion head,A,capable of being turned 180angular degrees in
16、 a plane normal to the torsion wire,B.Thetop of the wire shall be fastened to the torsion head passingthrough a loosely fitting sleeve,C.The bottom of the wire shallbe fastened to the test specimen clamp stud,D,by means of ascrew connector,E.A pointer,F,and movable protractor,G,shall be provided to permit convenient twist angle measure-ment and exact adjustment of the zero point.5.2 StandThe torsion apparatus shall be clamped to thesupporting stand,H.It is advantageous to make the verticalportio