GB/T 42918.3-2025 Plastics—Thermoplastic polyurethanes for moulding and extrusion—Part 3:Test method for distinction between ether and ester polyurethanes
GB/T 42918.3-2025 Plastics—Thermoplastic polyurethanes for moulding and extrusion—Part 3:Test method for distinction between ether and ester polyurethanes
Basic Information
Scope
This document describes two determination methods for distinguishing between polyether polyurethane and polyester polyurethane:
—— Method A: Chemical titration, which does not require sophisticated instruments. It is used for quality control and to avoid or reduce the need for microbial resistance testing on thermoplastic polyurethane (hereinafter referred to as TPU) materials;
—— Method B: Infrared spectroscopy, which requires sophisticated instruments and offers high detection accuracy. It is designated as an arbitration method and is limited to rapid qualitative analysis.
This document only applies to TPU based on 4,4-diphenylmethane diisocyanate (MDI), 4,4′-dicyclohexylmethane diisocyanate (HMDI), and hexamethylene diisocyanate (HDI) as raw materials. Among these, polyester TPU only includes conventional polyester TPU and polycaprolactone TPU, and does not include polycarbonate TPU.
This document is applicable to TPU quality control and provides detection methods for TPU stakeholders to distinguish between thermoplastic polyurethane types and characterize thermoplastic polyurethane mixtures. It also provides detection methods for TPU stakeholders to determine whether to conduct microbial degradation resistance and hydrolysis resistance tests.