Significance and Use
This test method measures the molecular weight distribution and molecular weight averages of polyethylene (except LDPE) and polypropylene resins. Differences in molecular weight and molecular weight distribution significantly affect physical properties, such as morphology, strength, melt flow etc., and as a result, the final properties of products made from these resins.
1. Scope
1.1 This test method covers the determination of molecular weight distributions and molecular weight averages of linear polyolefins by high temperature gel permeation chromatography (GPC). This test method uses commercially available polystyrene standards and equipment and is applicable to polyethylenes (excluding high pressure low density polyethylene-LDPE) and polypropylenes soluble in 1,2,4-trichlorobenzene (TCB) at 140C. This test method is not absolute and requires calibration.
Note 1Size exclusion chromatography (SEC) often is used as an alternative name for gel permeation chromatography (GPC).
Note 2Specific methods and capabilities of users may vary with differences in columns, instrumentation, applications software, and practices between laboratories.
Note 3One general method is outlined herein; alternative analytical practices can be followed and are attached in notes where appropriate.
Note 4There is no similar or equivalent ISO standard.
1.2 The values stated in SI units, based on IEEE/ASTM S1-10, are to be regarded as the standard.
This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents (purchase separately) 
The documents listed below are referenced within the subject standard but are not provided as part of the standard.
ASTM Standards
D883 Terminology Relating to Plastics
D3016 Practice for Use of Liquid Exclusion Chromatography Terms and Relationships
D5296 Test Method for Molecular Weight Averages and Molecular Weight Distribution of Polystyrene by High Performance Size-Exclusion Chromatography
E685 Practice for Testing Fixed-Wavelength Photometric Detectors Used in Liquid Chromatography
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
Keywords
gel permeation chromatography; molecular weight average; molecular weight distribution; polyolefin; size exclusion chromatography;
ICS Code
ICS Number Code 83.080.20 (Thermoplastic materials)
DOI: 10.1520/D6474-99R06
ASTM International is a member of CrossRef.
Citing ASTM Standards
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