Tailoring the performance of waterborne polyurethanes through composition control and structural optimization to meet the highly diversified modern demands is still one of the primary challenges faced by the polyurethane industry. Herein, various natural phenolic acids as neutralizers, for the first time, were applied for the preparation of castor oil-based cationic waterborne polyurethanes (CWPUs). The effects of these neutralizers on the microstructure (phase separation and hydrogen bond) and performance (mechanical properties, antibacterial activities, etc.) of the CWPUs were systematically investigated and compared with those of other commonly used neutralizers. The results indicate that apart from serving as neutralizers, phenolic acids also acted as antiplasticizing agents for the CWPU films by increasing the rigidity of the hard segment and hydrogen bond number. Also, the hydrophobic, rigid, conjugated structure of phenolic acids endowed the resulting CWPU films with excellent water resistance and UV protection. The introduction of phenolic acids also endowed the resulting polyurethane films with good antibacterial performance against both Gram-positive and Gram-negative bacteria. This study provides a novel and facile approach to tailor the performance of environmentally friendly cationic waterborne polyurethanes through natural phenolic acid neutralizers, along with eliminating long-standing issues of WPUs, such as irritating odor and air pollution.

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不同天然酚醛酸增强阳离子水性聚氨酯的机械性能和功能性能

通过组成控制和结构优化来调节水性聚氨酯的性能以满足高度多样化的现代需求，仍然是聚氨酯工业面临的主要挑战之一。本文中，首次将各种天然酚酸作为中和剂，用于制备蓖麻油基阳离子水性聚氨酯（CWPU）。系统研究了这些中和剂对CWPU的微观结构（相分离和氢键）和性能（机械性能，抗菌活性等）的影响，并与其他常用中和剂进行了比较。结果表明，除了充当中和剂外，酚酸还可以通过增加硬链段的刚性和氢键数来用作CWPU膜的抗增塑剂。而且，酚酸的疏水性，刚性，共轭结构使所得的CWPU膜具有出色的耐水性和紫外线防护能力。酚酸的引入也使所得的聚氨酯膜对革兰氏阳性和革兰氏阴性细菌均具有良好的抗菌性能。这项研究提供了一种新颖且简便的方法，可以通过天然酚酸中和剂来调整环保型阳离子水性聚氨酯的性能，同时消除WPU的长期存在的问题，例如刺激性气味和空气污染。酚酸的共轭结构使所得的CWPU薄膜具有出色的耐水性和紫外线防护能力。酚酸的引入也使所得的聚氨酯膜对革兰氏阳性和革兰氏阴性细菌均具有良好的抗菌性能。这项研究提供了一种新颖且简便的方法，可以通过天然酚酸中和剂来调整环保型阳离子水性聚氨酯的性能，同时消除WPU的长期存在的问题，例如刺激性气味和空气污染。酚酸的共轭结构使所得的CWPU薄膜具有出色的耐水性和紫外线防护能力。酚酸的引入也使所得的聚氨酯膜对革兰氏阳性和革兰氏阴性细菌均具有良好的抗菌性能。这项研究提供了一种新颖且简便的方法，可以通过天然酚酸中和剂来调整环保型阳离子水性聚氨酯的性能，同时消除WPU的长期存在的问题，例如刺激性气味和空气污染。