1、Designation:D323615(Reapproved 2021)Standard Test Method forApparent Viscosity of Hot Melt Adhesives and CoatingMaterials1This standard is issued under the fixed designation D3236;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the y
2、ear 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.1.Scope1.1 This test method covers the determination of the appar-ent viscosity of hot melt adhesives and coating materialscomp
3、ounded with additives and having apparent viscosities upto 200 000 millipascal second(mPas)(Note 3)at temperaturesup to 175 C(347 F).NOTE1Although precision has not been studied,this procedure maybe adaptable to viscosities higher than the present 200 000 mPas limit andtemperatures above 175 C(347 F
4、).Equipment described in this testmethod permits testing of materials having viscosities as high as16 106mPas and provides temperatures up to 260 C(500 F).NOTE2For petroleum waxes and their blends having apparentviscosities below 15 mPas,Test Method D445 is especially applicable.NOTE3One pascal seco
5、nd(Pas)=1000 centipoise(cP);one milli-pascal-second=one centipoise.1.2 The values stated in SI units are to be regarded as thestandard.The values in parentheses are for information only.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is there
6、sponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-iz
7、ation established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D445 Test Method for Kinematic Viscosity of Transparenta
8、nd Opaque Liquids(and Calculation of Dynamic Viscos-ity)3.Terminology3.1 Definitions:3.1.1 apparent viscosity,nthe viscosity determined by thistest method and expressed in millipascal seconds.Its valuemay vary with the spindle and rotational speed selectedbecause many hot melts are non-Newtonian.3.1
9、.2 viscosity,nthe ratio of shear stress to shear rate.Theviscosity of a liquid is a measure of the internal friction of theliquid in motion.The unit of dynamic viscosity is the pascalsecond.For a Newtonian liquid,the viscosity is constant at allshear rates.For a non-Newtonian liquid,viscosity will v
10、arydepending on shear rate.4.Summary of Test Method4.1 A representative sample of the molten material to betested is maintained in a thermally controlled sample chamber.Apparent viscosity is determined under temperature equilib-rium conditions using a precision rotating spindle type viscom-eter.Data
11、 obtained at several temperatures can be plotted onappropriate semi-logarithmic graph paper and apparent viscos-ity at intermediate temperatures can be estimated.5.Significance and Use5.1 This test method distinguishes between hot melts havingdifferent apparent viscosities.It is believed that appare
12、ntviscosity determined by this procedure is related to flowperformance in application machinery operating under condi-tions of low shear rate.Apparent viscosity as determined bythis test method may not correlate well with end-use applica-tions where high shear rates are encountered.5.2 Materials of
13、the type described in this procedure may bequite non-Newtonian and as such,the apparent viscosity willbe a function of shear rate under the conditions of test.Although the viscometer described in this test method gener-ally operates under conditions of relatively low shear rate,differences in shear
14、effect can exist depending upon the spindleand rotational speed conditions selected for the test program.Maximum correlation between laboratories,therefore,dependsupon testing under conditions of equivalent shear.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,
15、Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.10.0A on Physical/Chemical Properties.Current edition approved Jan.1,2021.Published February 2021.Originallyapproved in 1973.Last previous edition approved in 2015 as D3236 15.DOI:10.1520/D3236-15R21.2For referenced ASTM
16、 standards,visit the ASTM website,www.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 StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment
