ISO 17190-4:2020

Overview

ISO 17190-4:2020 specifies a test method for estimating the moisture content of polyacrylate superabsorbent powders used in urine-absorbing aids for incontinence. This international standard focuses on measuring moisture by quantifying weight loss upon heating the polymeric superabsorbent powder at a controlled temperature. The method is suitable for cross-linked polyacrylate superabsorbent powders that remain free-flowing under test conditions. It provides a reliable and reproducible procedure to assess moisture levels critical for quality control, product performance, and safety in absorbent aids.

Key Topics

• Scope and applicability: Applies to powdered polymeric superabsorbent materials incontinence products; excludes powders with volatile substances other than water interfering at test temperature.
• Test principle: Measurement of mass loss after heating samples at (105 ± 2) °C in an electrically heated oven until achieving constant weight.
• Sampling and preparation: Protocols for sample homogenization, lump removal, and conditioning under standard climate-controlled laboratory conditions (23 ± 2) °C and 45 ± 15% RH.
• Equipment required:
  • Analytical balance with ±0.001 g accuracy
  • Air-circulating thermostatic drying oven
  • Desiccator with indicating silica gel for sample cooling
  • Spatula and drying containers (glass or aluminium dishes)
• Testing procedure:
  • Dry container and lid to constant weight
  • Weigh container before and after adding approximately 4 g sample
  • Heat the sample uncovered for 3 hours at specified temperature
  • Cool sample in desiccator and weigh after drying
• Calculation: Moisture content (%) calculated from difference in mass before and after drying relative to sample weight.
• Repeatability and reproducibility: Validated precision data with repeatability (r) and reproducibility (R) statistics for moisture contents ranging from 0.4% to 1.82%.

Applications

ISO 17190-4:2020 is essential for manufacturers, quality control laboratories, and researchers involved in producing or testing urine-absorbing aids and incontinence products containing polyacrylate superabsorbent powders. Accurate moisture content determination ensures:

• Product consistency and quality: Maintaining optimal moisture levels supports superabsorbent performance in adult diapers, feminine hygiene products, and medical absorbents.
• Safety compliance: Controlling moisture reduces risks of microbial growth and prolongs shelf life.
• Formulation validation: Assists polymer producers in evaluating moisture content impact and adjusting processing parameters accordingly.
• Regulatory adherence: Aligns with international best practices for standardized testing methods in assistive product development.
• Research and development: Supports improved superabsorbent materials by enabling precise moisture measurements during material characterization.

Related Standards

• ISO 17190 series: Covers various characteristics and test methods for superabsorbent polymers in urine-absorbing aids.
• ISO 187: Standard atmosphere for conditioning and testing of materials, referenced for sample conditioning procedures.
• NWSP 230.0: Method for pH determination in polyacrylate superabsorbent powders.
• Relevant health and safety guidelines: Includes exposure limits for respirable superabsorbent polyacrylate dust (e.g., MAK Commission recommendations for occupational health).

By adhering to ISO 17190-4:2020, stakeholders in the incontinence aid industry can ensure accurate determination of moisture content in polyacrylate superabsorbent powders, supporting improved product reliability, regulatory compliance, and market acceptance worldwide. This standard forms a critical part of quality assurance for superabsorbent polymer testing, emphasizing practical, repeatable procedures for laboratory use.