1、Designation: E28 99 (Reapproved 2009)E28 14Standard Test Methods forSoftening Point of Resins Derived from Naval Stores PineChemicals and Hydrocarbons, by Ring-and-Ball Apparatus1This standard is issued under the fixed designation E28; the number immediately following the designation indicates the y
2、ear of originaladoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Depar
3、tment of Defense.1. Scope1.1 These test methods are intended for determining the softening point of resins (including rosin and terpene resins) and similarmaterials by means of the ring-and-ball apparatus.NOTE 1For testing asphalts, tars, and pitches, see Test Method D36.1.1.1 Test method using the
4、manualautomated ring and ball softening point apparatus, apparatus is the reference method and1.1.2 Test method using an automatedthe manual ring and ball softening point apparatus.apparatus is an alternative method.1.2 The values stated in SI units are to be regarded as the standard. The values giv
5、en in parentheses are for information only.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulator
6、ylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D36 Test Method for Softening Point of Bitumen (Ring-and-Ball Apparatus)E1 Specification for ASTM Liquid-in-Glass ThermometersE177 Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE691 Practice for Conducting an
7、 Interlaboratory Study to Determine the Precision of a Test Method3. Significance and Use3.1 In general, with materials of these types, softening does not take place at a definite temperature. As the temperature rises,these materials gradually change from brittle or exceedingly thick and slow-flowin
8、g materials to softer and less viscous liquids.For this reason, the determination of the softening point must be made by a fixed, arbitrary, and closely defined method if the resultsobtained are to be comparable.3.2 In these test methods, the softening point is defined as the temperature at which a
9、disk of the sample held within a horizontalring is forced downward a distance of 25.4 mm (1 in.)mm (1 in.) under the weight of a steel ball as the sample is heated at 5C/minin a water, glycerin, silicone oil, ethylene glycol/water or glycerin/water bath.3.3 The automatic method was chosen to be the
10、reference method because a round robin demonstrated that it gave more preciseresults than the manual method.4. Sample Preparation4.1 Preparation of Sample by the Pour Method:4.1.1 This procedure is suitable for materials that can be heated and poured without adverse effects on the softening point.1
11、These test methods are under the jurisdiction of ASTM Committee D01 on Paint and Related Coatings, Materials, and Applications and are the direct responsibility ofSubcommittee D01.34 on Pine Chemicals and Hydrocarbon Resins.Current edition approved June 1, 2009July 1, 2014. Published June 2009August
12、 2014. Originally approved in 1936. Last previous edition approved in 20042009 asE28 99 (2004).(2009). DOI: 10.1520/E0028-99R09.10.1520/E0028-14.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsv
13、olume information, refer to the standardsstandards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possi
14、ble to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, Wes
15、t Conshohocken, PA 19428-2959. United States14.1.2 Select a sample representative of the material to be tested. The sample should consist of flakes, pastilles, or freshly brokenlumps free of oxidized surfaces. Avoid inclusion of finely divided material or dust.4.1.3 Select a quantity at least twice
16、that necessary to fill the desired number of rings, and melt it immediately in a cleancontainer, using an oven, hot plate, sand bath or oil bath to prevent local overheating. Take care to avoid incorporating air bubblesin the sample. Melt the sample completely, but do not heat it above a temperature
17、 necessary to pour the material readily. The timefrom the beginning of heating to the pouring of the sample should not exceed 15 min.NOTE 2For materials that may be heat sensitive, continuously inert the flask containing the test specimen with nitrogen (N2) during the remeltingprocedure.4.1.4 For ma
18、terials that tend to crack or shrink in the ring on cooling, immediately before filling the ring, preheat the ring toapproximately the temperature at which the material is to be poured. The ring, while being filled, should rest bottom down on asuitable metal surface. Pour the sample into the ring so
19、 as to leave an excess on cooling.After cooling a minimum of 30 min, trimoff the excess resin on the periphery of the ring. To remove excess resin from the top, cut the excess material off cleanly with aslightly heated knife or spatula, or grasp the ring in a pair of tongs and draw the top surface q
20、uickly and firmly over the surfaceof a heated metal plate. In case the test is repeated, use a clean container and fresh sample.4.2 Preparation of Sample by the Molding Method:4.2.1 See Appendix X1, Alternate Sample Preparation Procedures.4.3 Preparation of Samples Having a Low Softening Point (up t
21、o 35C (95F):4.3.1 Place a ring on a piece of aluminum foil. Pour the material to be tested into the ring, then place the foil and filled ringon dry ice or in a freezer to cool. The material in the ring must be free of bubbles.4.3.2 After cooling, cut and scrape off any excess material using a slight
22、ly heated spatula, then slide the ring gently from thefoil. Place the ring in the supporting apparatus, and immediately perform the softening point analysis according to Section 11.5. Reagents and Materials5.1 Bath Liquids:5.1.1 Distilled or Deionized Water, Freshly BoiledFor softening points betwee
23、n 35C (95F) and 80C (176F).5.1.1.1 Use distilled or deionized water that has been cooled to at least 27C (81F) below the anticipated softening point, butin no case lower than 5C (41F).5.1.2 USP GlycerinFor softening points between 80C (176F) and 150C (302F). Repeated use of glycerin will increase th
24、emoisture content over time and may affect results. Replace with fresh glycerin if any change in appearance is noted.NOTE 3Glycerin should not be used for softening points greater than 150C (302F) due to the 160C (320F) flash point of glycerin.5.1.3 Silicone Oil (Polydimethylsiloxane)For softening p
25、oints above 80C (176F). The silicone oil must have a temperaturerange of 200C + (392F), remain clear within the temperature range, have no apparent reactivity with the test specimen, have ahigh water repellency, and maintain a uniform viscosity and stirring rate within the temperature range.3NOTE 4R
26、eplace with fresh silicone oil if any change in appearance is noted. Do not use silicone oil that contains any gels; gels are an indicator thatdegradation has occurred.5.1.4 Ethylene GlycolGlycol/WaterFor softening points up to 35C (95F).5.1.4.1 Prepare a fresh 50/50 (v/v) mixture of distilled water
27、 and ethylene glycol prior to sample analysis. For softening pointsbetween 0C and 35C, a 50/50 (v/v) mixture of glycerin and water may be used.REFERENCE METHODAUTOMATED RING AND BALL SOFTENING POINT METHOD6. Apparatus6.1 Automated Ring and Ball-Softening Point Instrument with Control Unit, test unit
28、s, and test inserts.6.2 RingA brass, shouldered ring conforming to the dimensions shown in Fig. 1(a).6.3 BallA steel ball, 9.53 6 0.1 mm (38 in.) in diameter, weighing between 3.45 and 3.55 g.6.4 Beaker, 600 mL or what is recommended by the manufacturer. Ensure that the dimensions will properly fit
29、the heating unit.6.5 Stir BarThe dimensions must be such that the bar spins freely under the test stand. It is recommended that the stirringbar supplied with the instrument be used or one that has been shown to give the same result as the one supplied.3 The sole source of supply of silicone oil, 200
30、 fluid, 50 cSt viscosity known to the committee at this time is Dow Corning Corp., Midland, MI 48686. If you are awareof alternative suppliers, please provide this information toASTM International Headquarters.Your comments will receive careful consideration at a meeting of the responsibletechnical
31、committee,1 which you may attend.E28 1427. Procedure for Materials Having a Softening Point Between 35C (95F) and 80C (176F)7.1 Add a stir bar to the 600mL beaker and fill with approximately 500 mL of distilled or deionized water, conforming to therequirements in 5.1.1. Ensure that the beaker is pro
32、perly positioned on the heater in the test unit. Place the prepared sample ringsin the test insert. Place the ball-centering guide and ball on top of the sample ring. Place the test insert in the beaker of water,suspending it from the support pins. Place the temperature measuring device in the test
33、insert. Verify that the control unit is setfor the correct bath liquid.7.2 HeatingHeat the bath so that the temperature of the water is raised uniformly at a rate of 5C (10F)/min. Protect the bathfrom drafts, using shields if necessary. The maximum permissible variation for any one min. period after
34、 the first three min. is60.5C (61F). Reject any test in which the rate of temperature rise does not fall within these limits. The test is complete whenthe light beam has been interrupted by the falling ball and material.NOTE 5Rigid adherence to the prescribed rate of heating is absolutely essential
35、for reproducibility of results.7.3 Softening PointRecord as the softening point the temperature displayed on the unit after the light beam has beeninterrupted by the falling ball and material.7.4 Start the cooling process in the instrument. Remove the temperature measuring device from the test inser
36、t, then remove thetest insert from the beakers. Thoroughly clean the test insert, ball, and ring in a suitable solvent.8. Calibration8.1 The calibration of any automated ring and ball-softening point apparatus must be performed on a regular basis since accuratetemperature control is required. Follow
37、 the manufacturers instructions for calibration of the instrument.FIG. 1 Shouldered Ring, Ring Holder, Ball-Centering Guide, and Assembly of Apparatus Showing Two RingsE28 1439. Procedure for Materials Having Softening Points Between 80C (176F) and 150C (302F)9.1 Use the same procedure as described
38、in Section 7, except fill the bath with glycerin or silicone oil.NOTE 6For materials softening around 80C (176F), report the bath liquid since a glycerin or silicone oil bath will yield a slightly higher result thana water bath.10. Procedure for Materials Having Softening Points Above 150C (302F)10.
39、1 Use the same procedure as described in Section 7, except fill the bath with silicone oil (Note 3).11. Procedure for Materials Having Softening Points Below 35C (95F)11.1 Apparatus:11.1.1 Freezer or Isopropyl Alcohol Dry-Ice Bath.11.2 Procedure:11.2.1 Cool the bath, described in 5.1.4.1, to 25C (13
40、F) in the precooled freezer or an isopropyl alcohol dry-ice bath.11.2.2 Use the same procedure as in Section 7. Take care to immediately begin heating as directed once the test specimen inthe ring has been placed in the bath.12. Report12.1 Report the softening point to the nearest 1.0C.12.2 Report t
41、he bath liquid used in the test.ALTERNATE METHODMANUAL RING AND BALL SOFTENING POINT METHOD13. Apparatus13.1 Ring and Ball Apparatus, consisting of the following:13.1.1 RingA brass, shouldered ring conforming to the dimensions shown in Fig. 1(a).13.1.2 BallA steel ball, 9.53 6 0.1 mm (38 in.) in dia
42、meter, weighing between 3.45 and 3.55 g.13.1.3 Ball-Centering GuideA brass guide for centering the ball conforming to the general shape and dimensions shown inFig. 1(c), the use of which is optional.13.2 Support for Ring and ThermometerAny convenient method for supporting the ring and thermometer ma
43、y be used,provided it meets the following requirements:13.2.1 The ring must be supported in a substantially horizontal position.13.2.2 When using the apparatus shown in Fig. 1(d): The bottom of the ring must be 25.4 6 0.2 mm (1.0 in.) above thehorizontal plate below it; the bottom surface of the hor
44、izontal plate must be 12.7 to 19.05 mm (0.5 to 0.75 in.) above the bottomof the beaker.13.2.3 Suspend a thermometer so that the bottom of the bulb is level with the bottom of ring and within 12.7 mm (0.5 in.) butnot touching the ring or the ring holder.13.3 BathA heat-resistant glass beaker, at leas
45、t 85 mm (3.34 in.) in diameter and 127 mm (5 in.) in depth from the bottomof the flare, for example, an 800-mL low-form Griffin beaker.13.4 Temperature Measuring DeviceA thermometer having a range described below and conforming to the requirementsprescribed in Specification E1, or an electronic temp
46、erature measuring device, such as a resistance thermometer or thermocouple.The device must exhibit the same temperature response as the thermometers specified in Specification E1 and must be accuratelycalibrated.13.4.1 An ASTM Thermometer, An ASTM Thermometer, having a range from 38 to +50C (36 to +
47、120F), ASTM 5C, 5F,or equivalent.any temperature measuring device having equivalent precision.13.4.2 An ASTM Low-Softening-Point Thermometer, An ASTM Low-Softening-Point Thermometer, having a range from 2 to80C (30 to 180F), ASTM 15C, 15F or equivalent.15F, or any temperature measuring device having
48、 equivalent precision.13.4.3 An ASTM Medium-Softening Point Thermometer, AnASTM Medium-Softening Point Thermometer, having a range from30 to 200C (85 to 392F), ASTM 16C, 16F or equivalent.16F, or any temperature measuring device having equivalent precision.13.4.4 An ASTM High-Softening-Point Thermom
49、eter, An ASTM High-Softening-Point Thermometer, having a range from 2to 300C (30 to 580F), ASTM 7C, 7F or equivalent.7F, or any temperature measuring device having equivalent precision.13.5 StirrerStirerThe heating bath must be stirred at a speed sufficient to ensure uniform heat distribution without causingsignificant sideways displacement of the resin as it softens in the ring. A stirring rate of 500 to 700 r/min is typical. A mechanicalmotor-driven stirrer, mounted so that any vibratio
