EN ISO 13885-2:2021

Overview

EN ISO 13885-2:2021 – "Gel permeation chromatography (GPC) - Part 2: N,N‑Dimethylacetamide (DMAC) as eluent" specifies a standardized procedure for measuring the molar‑mass distribution and average molar masses Mn (number average) and Mw (weight average) of polymers that are soluble in DMAC using gel permeation chromatography (GPC), also known as size exclusion chromatography (SEC). Prepared by ISO/TC 35 and adopted by CEN, this part of the ISO 13885 series focuses on using N,N‑Dimethylacetamide (DMAC) as the eluent and defines requirements for apparatus, calibration, data evaluation and reporting.

Key topics and technical requirements

• Scope & limitations
  • Applicable only to polymers soluble in DMAC.
  • Not suitable for samples with Mw > 10^6 g·mol⁻1 or with elution limits outside the calibration range.
  • Does not include correction methods for peak broadening; absolute molar‑mass methods are recommended if required.
• Apparatus & consumables
  • Specifications for eluent supply, pumps, injection systems, separation columns, column temperature control and detectors.
  • Recommendations for reagents and sample preparation compatible with DMAC.
• Calibration & standards
  • Requirements for calibration standards, preparation of calibration solutions and plotting the calibration curve (calibration range is critical).
• Data acquisition & evaluation
  • Procedures for baseline determination, net chromatogram calculation, evaluation limits, calculation of Mn, Mw and distribution curves.
• Precision & reporting
  • Guidance on repeatability, reproducibility and required elements of the test report.
• Warnings
  • Potential for specific interactions (e.g., adsorption) within the sample/eluent/column system that may invalidate results.

Practical applications and users

• Primary users:
  • Polymer scientists, analytical chemists, QC/QA laboratories, R&D teams in polymer, coatings (paints & varnishes), adhesives and binder industries.
• Typical uses:
  • Routine characterization of polymer molar‑mass distribution for quality control and batch release.
  • Comparative testing during formulation development, process optimisation and troubleshooting solvent‑polymer interactions.
  • Defining calibration procedures and method validation for labs using DMAC eluent in GPC/SEC.
• When absolute values are needed:
  • Use membrane osmometry for Mn or light scattering for Mw, as noted in the standard.

Related standards

• Part of the ISO 13885 series on GPC/SEC methods (consult national body for the full list).
• EN ISO 13885-2:2021 is the CEN-adopted version of ISO 13885-2:2020. For complementary procedures, refer to other parts of ISO 13885 and national standards on GPC solvents and absolute molar‑mass techniques.