ASTM_D_3837_-_95_2012.pdf

Designation:D383795(Reapproved 2012)Standard Practice forPreparing a Solution of AlkaliSoluble Resins1This standard is issued under the fixed designation D3837;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 practice is a procedure for preparing solutions ofalkali-soluble resins in aqueous ammonia and determining thecharacteristics of such solutions.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 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:2D1544 Test Method for Color of Transparent Liquids(Gard-ner Color Scale)D2834 Test Method for Nonvolatile Matter(Total Solids)inWater-Emulsion Floor Polishes,Solvent-Based FloorPolishes,and Polymer-Emulsion Floor PolishesE70 Test Method for pH of Aqueous Solutions With theGlass Electrode3.Summary of Practice3.1 Alkali-soluble resins are dissolved in water by chemi-cally reacting available carboxylic acid sites on the resinmolecule with a base to form water-soluble carboxylate salts.In this practice,the base used is ammonium hydroxide.4.Significance and Use4.1 This practice is suitable for all types of akalali-solubleresins.The resin manufacturer shall specify the percent am-monium hydroxide to be used(based on the equivalent weightof resin)and the maximum temperature to be used to achievesolution.5.Reagents and Materials5.1 Reaction VesselA three-neck,round-bottom 1000-mLflask of heat-resistant glass.5.2 Thermometer,laboratory grade,partial immersion ther-mometer.Range:from 0 to 230F,2 divisions;or from 20 to110C,1 divisions.5.3 Reflux Condenser.5.4 StirrerA motor-driven,variable-speed agitator.Theshaft and blade shall be of nonreactive material.5.5 Heat SourceElectric heating mantle or gas burner.5.6 Ammonium Hydroxide,reagent grade,28 to 30%NH3(26 Baum).This solution shall be refrigerated while instorage.5.7 Distilled Water,or water of equal purity.6.Preparation of Sample6.1 Resin received in ground or flaked form shall be used asreceived.Select a sample representative of the material undertest.6.2 Resin received in lump form shall be crushed or groundand passed through a 10-mesh screen before testing.Select asample representative of the material under test.7.Procedure7.1 Insert the reflux condenser into one of the sidearms ofthe flask and support the assembly suitably.Insert the agitatorthrough the center neck and charge the flask with the calculatedamount of ammonium hydroxide and water.Using moderateagitation,slowly add the resin to the contents of the flask.Adjust the agitator speed as necessary to keep the resinsuspended and moving,but not so fast as to entrain air into thesolution.Heat the solution to the specified temperature within10 min,and maintain this temperature until the solution iscomplete,or for a maximum of 30 min.If the solution is cloudyor hazy at this point,add additional ammonium hydroxide toclear solution.Total heating time shall not exceed 40 min.Coolthe solution and transfer to a clear,clean glass bottle.NOTE1Any deviation from this procedure shall be specified by theresin manufacturer,for example,pre-wetting of resin prior to NH4OHadditive.1This practice is under the jurisdiction of ASTM Committee D21 on Polishesand is the direct responsibility of Subcommittee D21.02 on Raw Materials.Current edition approved Oct.1,2012.Published October 2012.Originallyapproved in 1979.Last previous edition approved in 2007 as D383795(2007).DOI:10.1520/D3837-95R12.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 8.Calculation8.1 Solution weight desired(400 to 700 g suggested)timespercent solids desired equals weight of resin.8.2 Weight of resin times percent ammonium hydroxidespecified equals weight of ammonium hydroxide.8.3 Solution weight minus resin weight minus ammoniumhydroxide weight equals weight of water.8.4 Example400 g of a 15%solids solution is desired.The specified amount of ammonium hydroxide is 25%of theweight of the resin.The calculations are as follows:400 g 30.155 60 g resin(1)60 g 30.255 15 g ammonium hydroxide(2)400 g 2 60 g 2 15 g 5 325 g water(3)9.Report9.1 Report the following information:9.1.1 Percent solids of the solution(Test Method D28344h),9.