Open Access

ARTICLE

Rapid-Curing, Precision-Sprayable Polyoxytetramethylene Glycol Based Polyurethane-Urea Coatings with High Mechanical Performance

Zhipeng Ran^*, Peishuang Xiao, Shuen Liang, Keping Chen, Xiuli Zhao^*
Institute of Chemical Materials, China Academy of Engineering Physics, Mianyang, 621900, China
* Corresponding Author: Zhipeng Ran. Email: ; Xiuli Zhao. Email:

Journal of Polymer Materials https://doi.org/10.32604/jpm.2026.074431

Received 11 October 2025; Accepted 30 December 2025; Published online 20 January 2026

Abstract

This study presents the development of high-performance, solvent-free polyurethane-urea (PU) elastomeric coatings engineered for rapid curing and precise sprayability. Utilizing polyoxytetramethylene glycol (PTMG) as the primary polyol and a static-mixing spraying technique, the formulations were systematically optimized. It was found that a soft-segment content of 64% yields optimal mechanical properties, achieving a remarkable tensile strength exceeding 30 MPa. Crucially, the incorporation of an ultra-low concentration (0.002 wt%) of dibutyltin dilaurate catalyst was sufficient to enhance curing completeness and mechanical performance while effectively eliminating moisture-induced foaming, a common challenge in solvent-free spray applications. The gel and tack-free times were successfully reduced to the order of minutes through strategic formulation with the chain extender dimethylsulfide-toluene diamine, minimizing reliance on high catalyst loadings. The resultant PTMG-based coatings exhibit exceptional comprehensive properties, including a tensile strength >30 MPa, elongation at break >400%, and a tear strength of 66 N/mm, significantly surpassing conventional polypropylene-diamine-based polyurea systems. Furthermore, the coatings demonstrated superior low-temperature flexibility, evidenced by a glass transition temperature of −53°C, and suppressed soft-segment crystallinity. The solvent-free nature and tunable curing kinetics of this system enable precise spraying on complex geometries, effectively overcoming thickness-control limitations for small-object applications. This work establishes a sustainable and high-performance coating solution ideal for demanding impact- and corrosion-resistant protective layers.

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Keywords

Polyurethane-urea; coatings; mechanical performance; solvent-free

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