Overview
ISO 17190-2:2021 specifies a laboratory test method to determine the sum of residual monomeric sodium acrylate and acrylic acid present in polyacrylate superabsorbent powders used in urine‑absorbing aids (incontinence products). The result is reported as acrylic acid. The method uses solvent extraction followed by HPLC (high‑performance liquid chromatography) quantification and is applicable to routine quality control, product development and regulatory compliance testing.
Key Topics
- Scope & principle: Extraction of residual monomers from superabsorbent powder and HPLC analysis to quantify residual acrylate monomers as acrylic acid. The standard uses a 1 g : 200 ml mass:volume dilution as the reference dilution factor.
- Reagents & solvents: Grade‑specified water (ISO 3696), 0.9 % sodium chloride saline, phosphoric acid (diluted to 0.1 % w/w), acetonitrile (HPLC grade), and high‑purity acrylic acid reference material (>99.5 %).
- Calibration & standards: Preparation of calibration solutions (example concentrations: S3 = 1 mg/L, S4 = 2 mg/L, S5 = 3 mg/L, S6 = 4 mg/L). Calibration analyses are run in duplicate; duplicate peak areas must agree within 5% or be repeated.
- Apparatus & chromatography: HPLC system with C18 column (e.g., 100 mm × 4.6 mm, 5 µm), guard column, UV detector at 210 nm, injection volumes 10–100 µL, and 0.45 µm PTFE filtration for sample cleanup.
- Sampling & conditioning: Samples conditioned to laboratory atmosphere (preferred (23 ± 2) °C and (45 ± 15) % RH per ISO 187). Homogenize containers by gentle rotation; ensure no lumps >1 mm.
- Safety & handling: Warnings on concentrated acids and respirable superabsorbent dust; reference to MAK guideline (respirable fraction