Standard Test Method for Molecular Weight Averages and Molecular Weight Distribution of Polystyrene by High Performance Size- Exclusion Chromatography
|Publication Date:||1 September 2011|
This test method covers the determination of molecular weight (MW) averages and the distribution of molecular weights for linear, soluble polystyrene by high-performance size-exclusion chromatography (HPSEC). This test method is not absolute and requires the use of commercially available narrow molecular weight distribution (MWD) polystyrene standards for calibration. This test method is applicable for samples containing molecular weight components that have elution volumes falling within the elution volume range defined by polystyrene standards (that is, molecular weights generally from 2000 to 2 000 000 g·mol−1).
The HPSEC is differentiated from traditional size-exclusion chromatography SEC (also referred to as gel permeation chromatography (GPC)) in that the number of theoretical plates per metre with an HPSEC system is at least ten times greater than that for traditional SEC (see Terminology D883 and Practice D3016).2 The HPSEC systems employ low-volume liquid chromatography components and columns packed with relatively small (generally 3 to 20 μm) microporous particles. High-performance liquid chromatography instrumentation and automated data handling systems for data acquisition and processing are required.
The values stated in SI units 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. Specific precautionary statements are given in Section 9.
NOTE 1-There is no known ISO equivalent to this standard.
1 This test method is under the jurisdiction of ASTM Committee D20 on Plastics wide variety of and is the direct responsibility of Subcommittee D20.70 on Analytical Methods.
Current edition approved Sept. 1, 2011. Published September 2011. Originally approved in 1992. Last previous edition approved in 2005 as D5296 - 05. DOI: 10.1520/D5296-11.
2 See also AMD Bibliography and Bibliography Supplements AMD 40-S1, 40-S2, and 40-S3 on Size Exclusion Chromatography, available from ASTM Headquarters.
*A Summary of Changes section appears at the end of this standard.