Overview
ISO 10927:2018 specifies a standardized MALDI-TOF-MS method for determining the average molecular mass and molecular mass distribution of polymers. The scope covers polymer species with molecular masses from 2 000 g·mol−1 to 20 000 g·mol−1. Results are obtained as a relative method using calibration curves constructed from synthetic-polymer and/or biopolymer standards. The standard excludes polyolefins and polymers with polydispersity > 1.2.
Keywords: ISO 10927:2018, MALDI-TOF-MS, molecular mass distribution, polymers, calibration standards.
Key topics and requirements
- Scope and applicability
- Range: 2 000–20 000 g·mol−1.
- Not applicable to polyolefins or polymers with polydispersity >1.2.
- Principle
- Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS): laser desorption of polymer/matrix co-crystals, ionization, flight-time measurement and mass calibration.
- Reagents and consumables
- Recommended matrices: DHB (2,5-dihydroxybenzoic acid), DCTB, dithranol (≥97% purity).
- Solvents: THF (high-purity; antioxidant recommended), and optionally toluene, methanol, acetone depending on solubility.
- Salts for cationization: lithium, sodium, potassium, cesium and silver trifluoroacetate; AgNO3 with safety considerations.
- Standards and calibration
- Use synthetic or biopolymer calibrants with known repeating units/end groups within the target mass range (see Annex A).
- Mass-axis calibration methods described (synthetic and biopolymer calibrants, self-calibration).
- Instrumentation and data
- Components: sample target, laser source, flight tube (TOF), detector (linear/reflector), data acquisition and handling.
- Procedures: sample preparation, deposition, instrument settings, spectrum recording, data processing, and calculation of Mn, Mw, Mz and distribution.
- Reporting and precision
- Specifies calculation methods, precision data (Annex B), and required test-report content.
Applications and users
ISO 10927:2018 is valuable for:
- Polymer R&D and analytical laboratories performing molecular mass characterization.
- Quality control and specification testing in polymer production and polymer commerce.
- Academic researchers studying polymerization processes and structure–property correlations.
- Laboratories aiming to improve inter-lab comparability of MALDI-TOF-MS results through standardized methods.
Practical uses include rapid determination of average molecular masses and distributions for soluble polymers, process monitoring, and complementing size-exclusion chromatography (SEC/GPC) data where MALDI-TOF-MS is suitable.
Related standards
- ISO 472 (Plastics - Vocabulary) is referenced for terms and definitions.
- Developed by ISO/TC 61/SC 5 (Plastics - Physical-chemical properties).
For anyone implementing ISO 10927:2018, focus on compliant sample preparation, appropriate calibrants, and documented instrument settings to ensure reliable, comparable MALDI-TOF-MS polymer mass distributions.
Open preview (PDF)Plastics — Determination of the molecular mass and molecular mass distribution of polymer species by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS)
