ASTM_D_5097_-_90_1996.pdf

Designation:D 5097 90(Reapproved 1996)Standard Test Method forFilter-Retained Solids Content of Polymer Latexes1This standard is issued under the fixed designation D 5097;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(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the filter-retained solids(grit)content of polymeric latex vehicles,thatis,material present in a latex specimen that is retained on a200-mesh screen.1.2 The values stated in SI units are to be regarded asstandard.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:E 11 Specification for Wire-Cloth Sieves for Testing Pur-poses2E 145 Specification for Gravity-Convection and Forced-Ventilation Ovens23.Summary of Test Method3.1 A specified weight of a polymer latex,first filteredthrough a 20-mesh screen to remove skins and large agglom-erates,is water-washed through a preweighed 200-mesh stain-less screen.The dried residue on the screen,defined as thefilter-retained solids,is expressed as parts per million(ppm)ofthe polymer latex.NOTE1 Other screens or sample sizes,or both,may be used uponagreement between the producer and the user.Precision may vary withdiffering mesh size and sample weight.4.Significance and Use4.1 The amount of excessive oversized particulate matterpresent in polymer latexes can detract from the appearanceproperties of applied formulated coatings and may reducefiltration rates or clog filters in processing or applicationprocesses.4.2 This test method may be useful as a quality control testfor latex manufacture and for product characterization.5.Apparatus5.1 Analytical Balance,capable of weighing to 0.1 mg.5.2 Balance,capacity of 500 g,capable of weighing to 0.1g.5.3 Dessicator.5.4 Forced-Ventilation Oven,Type II B conforming toSpecification E 145.5.5 Forceps.5.6 Spectra Mesh Filtration Unit,3(90-mm size).5.7 Graduated Cyclinder,500-mL.5.8 Polyethylene Water Wash Bottle,500-mL.5.9 Two Beakers,800-mL.5.10 Screen,stainless steel,90-mm diameter,200-mesh(asdefined in Specification E 11).5.11 Screen,cloth or stainless steel,20-mesh(as defined inSpecification E 11).6.Procedure6.1 Weigh the clean,dry,200-mesh screen to the nearest 0.1mg.Record the weight,A.6.2 Place the screen into the filtration apparatus.NOTE2The screen should be held firmly in place while screwingdown the filter chamber to ensure that the screen seats smoothly on theplastic ring.6.3 Weigh 500 g of water into the 800-mL beaker and setaside.6.4 Hand-stir the polymer latex sample for about 15 s usinga wide blade spatula to ensure adequate mixing,taking care notto beat in air.Filter about 150 g of the latex sample through astandard 20-mesh cloth or stainless-steel sieve to remove skinsor large pieces of coagulum.6.5 Stir the filtered sample gently with the spatula.Imme-diately weigh out by difference about 50 g,weighed to 0.1 g,of the latex into an 800-mL beaker.Record the latex specimenweight,B.1This test method is under the jurisdiction of ASTM Committee D-1 on Paintand Related Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.33 on Polymers and Resins.Current edition approved July 27,1990.Published September 1990.2Annual Book of ASTM Standards,Vol 14.02.3The sole source of supply of the spectra mesh filtration unit,catalog number08-670-173 known to the committee at this time is Fisher Scientific Co.,711 ForbesAve.,Pittsburg,PA 15219-4785.If you are aware of alternative suppliers,pleaseprovide this information to ASTM Headquarters.Your comments will receivecareful consideration at a meeting of the responsible technical committee,1whichyou may attend.1AMERICAN SOCIETY FOR TESTING AND MATERIALS100 Barr Harbor Dr.,West Conshohocken,PA 19428Reprinted from the Annual Book of ASTM Standards.Copyright ASTM6.6 Transfer the 500 g of water from 6.3 to the beaker withthe specimen and stir the mixture with the spatula.NOTE3If the latex coagulates on water dilution,the test is notapplicable.6.7 Slowly pour the mixture onto the 200-mesh screen,water-washing the sample from the beaker onto the screen withthe polyethylene wash bottle.6.8 Wash the residue on the screen with 1000 g of water,using the wash bottle to wash down the sides of the filtrationapparatus and to move the solid toward the screen center.6.9 Specimen Drying:6.9.1 Carefully remove the screen from the apparatus usingforceps,place the screen in the oven and dry for 1 h at 110 61C.6.9.2 Remove the screen from the oven using the forcepsand allow the screen to cool for 10