1、Designation: D 2227 96 (Reapproved 2007)Standard Specification forNatural Rubber (NR) Technical Grades1This standard is issued under the fixed designation D 2227; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last rev
2、ision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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. Scope1.1 This specification covers minimum physical a
3、nd chemi-cal quality requirements or specifications for five grades of rawnatural rubber.2. Referenced Documents2.1 ASTM Standards:2D 1278 Test Methods for Rubber from Natural SourcesChemical AnalysisD 1485 Practice for Rubber from Natural SourcesSampling and Sample PreparationD 1646 Test Methods fo
4、r RubberViscosity, Stress Relax-ation, and Pre-Vulcanization Characteristics (Mooney Vis-cometer)D 3157 Test Method for Rubber from Natural SourcesColorD 3194 Test Method for Rubber From Natural SourcesPlasticity Retention Index (PRI)D 3533 Test Method for RubberNitrogen Content33. Detailed Requirem
5、ents for Grades3.1 The rubber shall conform to the requirements in Table 1.3.2 Any rubber not meeting all the requirements for one ofthe five grades in Table 1 cannot be considered a technicallygraded rubber.4. Significance and Use4.1 The general end-use quality of manufactured rubberproducts depend
6、s on the physical and chemical properties ofthe rubber.5. Classification5.1 TypesTable 1 covers the physical and chemical re-quirements for five grades of natural rubber: Grades L, CV, 5,10, and 20.6. Sampling6.1 The sampling and sample preparation shall be in accor-dance with Practice D 1485.7. Tes
7、t Methods7.1 Determine the properties enumerated in this specifica-tion in accordance with Test Methods D 1278, D 3533, D 3194,D 3157, and D 1646.8. Keywords8.1 natural rubber (NR); technical grade1This specification is under the jurisdiction ofASTM Committee D11 on Rubberand is the direct responsib
8、ility of Subcommittee D11.22 on Natural Rubber.Current edition approved March 1, 2007. Published May 2007. Originallyapproved in 1963. Last previous edition approved in 2002 as D 2227 96 (2002).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at s
9、erviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.TABLE 1 Specifications For Technically Graded Natural RubberPropertyRubber GradeAGradeLGradeCVBGrade5Grade10Grade20Dirt, retained on 45m sieve, % max0.050 0
10、.050 0.050 0.100 0.200Ash, % max 0.60 0.60 0.60 0.75 1.00Volatile matter, % max 0.80 0.80 0.80 0.80 0.80Nitrogen, % max 0.60 0.60 0.60 0.60 0.60Initial plasticity, min 30 . 30 30 30Plasticity retentionindex, min60 60 60 50 40Color index, max 6.0 . . . .Mooney viscosity . 6065 . . .ASkim rubber is no
11、t permitted in any grade, and Grades L, CV, and 5 must beproduced from intentionally coagulated latex.BOther Mooney ranges of Grade CV are available, CV- 50 6 5 and CV- 70 65. CV without suffix is the 60 6 5 as shown in the table.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, Wes
12、t Conshohocken, PA 19428-2959, United States.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, an
13、d the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revisi
14、on of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you sh
15、ouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 2227 96 (2007)2
