ASTM_D_3642_-_13.pdf

Designation:D364213Standard Test Method forSoftening Point of Certain Alkali-Soluble Resins1This standard is issued under the fixed designation D3642;the number immediately following the designation indicates the year oforiginal adoption or,in the 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.1.Scope1.1 This test method covers the determination of the soft-ening point of certain alkali-soluble resins having uniformplastic flow characteristics as the melting point is approached.1.2 The resin manufacturer should specify whether or notthis test method may be used for his product(s).1.3 This test method is not suitable for styrene-maleicanhydride resins.NOTE1For testing rosin and other resins,see Test Method E28.Fortesting asphalts,tars,and pitches,see Test Method D2398.1.4 This standard does not purport to address all of thesafety 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Documents2.1 ASTM Standards:2D2398 Test Method for Softening Point of Bitumen inEthylene Glycol(Ring-and-Ball)(Withdrawn 1984)3E28 Test Methods for Softening Point of Resins Derivedfrom Pine Chemicals and Hydrocarbons,by Ring-and-Ball ApparatusE2251 Specification for Liquid-in-Glass ASTM Thermom-eters with Low-Hazard Precision Liquids3.Terminology3.1 Definitions:3.1.1 softening pointthe temperature at which a disk of thesample held within a horizontal ring is forced downward adistance of 1 in.(25.4 mm)under the weight of a steel ball asthe sample is heated at a prescribed rate in a glycerin bath.4.Significance and Use4.1 In general,with materials of this type,softening doesnot take place at a definite temperature.As the temperaturerises,these materials gradually and imperceptibly change frombrittle solids to soft,viscous liquids.For this reason,thedetermination of the softening point must be made by a fixed,arbitrary,and closely defined methods if the results are to becomparable.5.Apparatus5.1 RingA brass-shouldered ring conforming to the di-mensions shown in Fig.1(a).5.2 BallA steel ball,9.53 mm(38in.)in diameter,weigh-ing between 3.45 and 3.55 g.5.3 Ball-Centering GuideA guide for centering the ball,constructed of brass and having the general shape and dimen-sions illustrated in Fig.1(c).5.4 ContainerA glass vessel,capable of being heated,notless than 85 mm(3.34 in.)in diameter and not less than 127mm(5 in.)in depth from the bottom of the flare.(An 800-mL,low-form Griffin beaker of heat-resistant glass meets thisrequirement.)5.5 Support for Ring and Thermometer,as shown in Fig.1(d).Note the following requirements:5.5.1 The ring shall be supported in a horizontal position.5.5.2 The bottom of the ring shall be 25.4 mm(1 in.)abovethe horizontal plate below it.5.5.3 The bottom surface of the horizontal plate shall be atleast 12.5 mm(0.5 in.)and not more than 19 mm(0.75 in.)above the bottom of the beaker.5.5.4 The depth of liquid in the beaker shall be not less than102 mm(4 in.).5.5.5 The thermometer shall be suspended so that thebottom of the bulb is level with the bottom of the ring andwithin 12.7 mm(0.5 in.)but not touching the ring.5.6 ThermometerAn ASTM High Softening PointThermometer,having a range from 30 to 200C,and conform-ing to the requirements for Thermometer 16C as prescribed inSpecification E2251.5.7 Mechanical StirrerA variable-speed,motor-drivenstirrer attached to the bottom of a true-vertical shaft must beused to ensure uniform heat distribution.The stirrer shall be1This test method is under the jurisdiction ofASTM Committee D21 on Polishesand is the direct responsibility of Subcommittee D21.02 on Raw Materials.Current edition approved Oct.1,2013.Published October 2013.Originallyapproved in 1978.Last previous edition approved in 2010 as D3642 98(2010).DOI:10.1520/D3642-132For referenced ASTM 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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 positioned and its speed shall be regulated so that the fluid inthe bath is completely but gently agitated,with no vortexing,turbulence,or air entrainment.6.Precautions6.1 Note the instructions concerning stirrer speed(5.7)andfollow closely.Take care that the stirrer motor does not impartvibrations to the bath through the support system.6.2 Previously boil the glycerin used in the bath in a fumehood.6.3 Rigid adherence to the prescribed rate of heating(Sec-tion 8)is absolutely essential to the accuracy and rep