ASTM_D_787_-_12.pdf

Designation:D78712Standard Specification forEthyl Cellulose Molding and Extrusion Compounds1This standard is issued under the fixed designation D787;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.This standard has been approved for use by agencies of the Department of Defense.1.Scope*1.1 This specification covers requirements for plasticizedethyl cellulose thermoplastic compounds suitable for injectionmolding and extrusion.It does not include special materialscompounded for special applications.1.2 The values stated in SI units are to be regarded asstandard.The English values given are for information only.1.3 The following precautionary statement pertains only tothe Test Methods portion,Section 10 of this specification.Thisstandard does not purport to address all of the safety concerns,if any,associated with its use.It is the responsibility of the userof this standard to establish appropriate safety and healthpractices and determine the applicability of regulatory limita-tions prior to use.NOTE1There is no known ISO equivalent to this specification.2.Referenced Documents2.1 ASTM Standards:2D256 Test Methods for Determining the Izod PendulumImpact Resistance of PlasticsD570 Test Method for Water Absorption of PlasticsD618 Practice for Conditioning Plastics for TestingD638 Test Method for Tensile Properties of PlasticsD648 Test Method for Deflection Temperature of PlasticsUnder Flexural Load in the Edgewise PositionD785 Test Method for Rockwell Hardness of Plastics andElectrical Insulating MaterialsD792 Test Methods for Density and Specific Gravity(Rela-tive Density)of Plastics by DisplacementD883 Terminology Relating to PlasticsD1505 Test Method for Density of Plastics by the Density-Gradient TechniqueD3641 Practice for Injection Molding Test Specimens ofThermoplastic Molding and Extrusion MaterialsD3892 Practice for Packaging/Packing of Plastics3.Terminology3.1 Terms in this specification are in accordance withTerminology D883.4.Classification4.1 This specification covers two types and eleven grades ofethyl cellulose molding and extrusion compounds as classifiedin accordance with Table 1.Type I materials are generalpurpose and Type II are characterized by improved resistanceto impact,especially at low temperatures.The grades areclassified in accordance with their physical properties asspecified in Table 1.5.Ordering Information5.1 Purchase orders for,or inquiries about,the materialsdescribed in this specification shall identify the following:5.1.1 The number of this specification and the required typeand grade chosen from Table 1,for example,D787 Type 1,Grade 1.5.1.2 Supplementary requirements in accordance with thisspecification if necessary.5.1.3 Color and opacity within the limits defined in 6.4.5.1.4 Particle form and size if choice is available.5.1.5 Such other requirements as may be agreed between theseller and the purchaser.6.Materials and Manufacture6.1 Materials supplied under this specification shall be ethylcellulose plastics in the form of pellets unless otherwisespecified.6.2 Material supplied in these forms shall be as uniform incomposition and size and as free of contamination as can beachieved by good manufacturing practice.6.3 These materials may contain colorants in the nominalamounts ordinarily employed,but such additives shall not alterthe ability of the materials to meet the specified properties.6.4 The color and transparency or opacity of items fabri-cated under the conditions recommended by the manufacturer1This specification is under the jurisdiction of ASTM Committee D20 onPlastics and is the direct responsibility of Subcommittee D20.15 on ThermoplasticMaterials.Current edition approved Aug.1,2012.Published August 2012.Originallyapproved in 1944.Last previous edition approved in 2009 as D787 09.DOI:10.1520/D0787-12.2For 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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 of the material shall be comparable within commercial matchtolerances to the color and transparency or opacity of samplessubmitted in advance by the manufacturer and approved by thepurchaser.7.Physical Requirements7.1 Test specimens of the material shall conform to therequirements prescribed in Table 1.7.2 Molded specimens for those tests requiring them shallbe prepared as described in Section 10.7.3 Flow temperature of a given compound shall be within65C of the flow temperature designated in the contract ororder.7.4 Conformance