Widely applied waterborne polyurethane (WPUs) are expected to be functionalized with excellent mechanical property, ideal self-healing performance and desired recyclability, but it is a great challenge to integrate these attractive properties into a one pot WPU platform. Herein, a novel double ingredients waterborne polyurethane (2K-WPU-DA-x), found on the furan modified WPU-F and maleimide decorated WPU-M dispersions for Diels-Alder (DA) cross-linking reactions, was designed and projected which exhibited interesting enhanced-mechanical, self-healable and recyclable properties. The stability and appearance of these novel waterborne polyurethane emulsions were well studied. In the following, the reversible nature of direct DA/retro-DA reactions within the 2K-WPU-DA-x was extensively analyzed via FT-IR, UV–vis, and DSC measurements. On account of the DA bonds resulted cross-linked structure of 2K-WPU-DA-1/1, the stress and strain at the break increased by more than 20 MPa and 250% respectively compared with linear structural WPU-F. At the same time, relying on the thermal-responsive dissociation/reassociation of DA covalent bonds, 2K-WPU-DA-x films shown outstanding self-healing ability, with a self-healing efficiency beyond 95%. Moreover, owing to the reversibility of 2K-WPU-DA-x, the networks exhibited readily recyclable and reshaping properties, showing a desired thermoplasticity.

广泛应用的水性聚氨酯（WPU）有望以优异的机械性能，理想的自修复性能和所需的可回收性进行功能化，但是将这些吸引人的性能集成到一锅式WPU平台中是一个巨大的挑战。本文设计并预测了在呋喃改性的WPU-F和马来酰亚胺装饰的WPU-M分散体中用于Diels-Alder（DA）交联反应的新型双组分水性聚氨酯（2K-WPU-DA-x），表现出有趣的增强机械性能，自修复和可回收特性。这些新型水性聚氨酯乳液的稳定性和外观得到了很好的研究。在下文中，直接DA /复古的可逆性通过FT-IR，UV-vis和DSC测量，对2K-WPU-DA-x中的-DA反应进行了广泛分析。由于DA键导致2K-WPU-DA-1 / 1的交联结构，与线性结构的WPU-F相比，断裂时的应力和应变分别增加了20 MPa和250％以上。同时，依靠DA共价键的热响应解离/再结合，2K-WPU-DA-x膜表现出出色的自我修复能力，自我修复效率超过95％。此外，由于2K-WPU-DA-x的可逆性，这些网络表现出易于回收利用和重塑的特性，显示出所需的热塑性。