ASTM_D_5596_-_03_2009.pdf

Designation:D559603(Reapproved 2009)Standard Test Method ForMicroscopic Evaluation of the Dispersion of Carbon Blackin Polyolefin Geosynthetics1This standard is issued under the fixed designation D5596;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 equipment,specimen prepara-tion techniques,and procedures for evaluating the dispersion ofcarbon black in polyolefin geosynthetics containing less than5%carbon black by weight.1.2 This test method allows for a qualitative evaluation ofcarbon black agglomerates and other inclusions in polyolefingeosynthetics.This evaluation is based on carbon black dis-persion size calculated area within microscopic fields of view.1.3 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.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.NOTE1This test method is for the evaluation of carbon blackdispersion.This test method does not support or evaluate the distributionof carbon black.2.Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD3053 Terminology Relating to Carbon BlackD4439 Terminology for GeosyntheticsE7 Terminology Relating to Metallography3.Terminology3.1 Definitions:3.1.1 carbon black,na material consisting essentially ofelemental carbon black in the form of near spherical colloidalparticles and coalesced particle aggregates of colloidal size,obtained by partial combustion or thermal decomposition ofhydrocarbons.(D3053)3.1.2 carbon black agglomerate,na cluster of physicallybound and entangled aggregates.(D3053)3.1.3 geosynthetic,na planar product manufactured frompolymeric material used with soil,rock,earth,or other geo-technical engineering-related material as an integral part of aman-made project,structure,or system.(D4439)3.1.4 micrograph,na graphic reproduction of an object asseen through the microscope or equivalent optical instrument,at magnifications greater than ten diameters(micrograph).(E7)3.1.5 microtome,n(that is,sliding microtome)an appara-tus capable of cutting thin slices(less than 20 m in thickness)of various geosynthetic samples.3.1.6 polyolefin,na polymer prepared by the polymeriza-tion of an olefin(s)as the sole monomer(s).(D883)3.1.7 dispersion,na polyolefin product formulated withcarbon black.3.1.8 distribution,na property of a carbon black formu-lated polyolefin product that refers to the existence of streaks,light or dark,within a microsectioned sample.4.Summary of Test Method4.1 This test method consists of two parts:(1)microtomespecimen preparation and(2)microscopic evaluation.4.1.1 Microtome Specimen PreparationA sample isclamped in the sample holder,which can be raised or loweredprecisely in increments of approximately 1 m.A rigid knife isslid manually across the sample so that the specimens range inthickness from 8 to 20 m.4.1.2 Microtome specimen examination:These thin sectionsare evaluated microscopically calculating the largest agglom-erate or inclusion in each random field of view(Rf).Theassociated carbon dispersion chart can be used to assist todetermining shape and area5.Significance and Use5.1 Carbon black is added to many polymers to providelong-term resistance to ultraviolet-induced degradation.Toachieve this,carbon black should be dispersed uniformly1This test method is under the jurisdiction of ASTM Committee D35 onGeosynthetics and is the direct responsibility of Subcommittee D35.02 on Endur-ance Properties.Current edition approved June 1,2009.Published July 2009.Originally approvedin 1994.Last previous edition approved in 2003 as D5596 03.DOI:10.1520/D5596-03R09.2For 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 throughout the as-manufactured geosynthetic material.Thistest method is used to evaluate the uniformity of carbon blackdispersion.5.2 This test method is suitable only for those geosyntheticsthat can be sampled using a rotary or sledge microtome.Thegeometry,stiffness(hardness),or elasticity of some geosyn-thetic products precludes their being sampled with a micro-tome.The cross-sectional area of the geosynthetic must becomposed of a continuous solid polyolefin material to besampled using a microtome.5.3 Extruded and oriented geogrids will re