衣康酸靶向修复受损发丝：基于巯基共价键合的力学增强机制

doi:10.3969/j.issn.2097-2806.2026.06.010

摘要/Abstract

摘要：

该研究旨在解决化学处理导致的头发力学性能衰退问题。传统有机酸修复剂主要针对氢键等弱相互作用，对二硫键断裂引发的游离巯基修复效果有限。基于此，该文提出利用衣康酸（Itaconic acid）的α, β-不饱和羰基结构与游离巯基发生迈克尔加成反应，形成共价硫醚交联网络以增强头发机械性能。通过单根纤维拉伸测试（MTT690）、游离巯基定量（Ellman 法）及毛鳞片显微观察（HIROX），系统评估了衣康酸对还原损伤头发的修复机制。结果表明，衣康酸在质量分数（w/%）为2%，pH值为3.9时，修护效果最优，相较于受损头发的断裂载荷显著提升21%。重复三次衣康酸处理使受损发丝中游离巯基含量降低54.43%，证明其通过共价硫醚键与角蛋白交联。同时，多次衣康酸修护后，头发弹性梯度与断裂载荷分别显著提升16.67%和28.50%，远超琥珀酸（4.47%/13.85%）和柠檬酸（6.08%/15.85%），证明共价交联对提高力学性能起关键作用。此外，显微镜观察显示衣康酸有效修护受损毛鳞片的翘起与脱落，并保护毛鳞片减少疲劳循环损伤导致的横向断裂。这些发现揭示了衣康酸靶向修护受损发丝的作用机理，为开发高效头发修护产品提供了新策略。

关键词: 衣康酸, 头发修护, 迈克尔加成, 游离巯基, 角蛋白, 力学性能, 毛鳞片

Abstract:

This study aims to address the deterioration of mechanical properties in chemically treated hair. Conventional organic acid reparatives target weak molecular interactions （e.g., hydrogen bonds）, but exhibit limited efficacy in repairing free sulfhydryl groups generated by disulfide bond cleavage. Herein, we propose leveraging the α, β-unsaturated carbonyl structure of itaconic acid to initiate a Michael addition reaction with free sulfhydryl groups, thereby forming covalent thioether cross-linked networks to enhance the mechanical performance of hair. The reparative mechanism of itaconic acid on reductively damaged hair was systematically evaluated through single-fiber tensile testing （MTT690）, free sulfhydryl quantification （Ellman’s assay）, and cuticle microscopy （HIROX）. The results demonstrate that itaconic acid （w=2%, pH=3.9） maximally restores damaged hair integrity, significantly increasing the breaking load by 21% （P<0.05） compared to the damaged hair. Meanwhile, after multiple itaconic acid treatments, the elastic gradient and breaking load increase by 16.67% and 28.50%, respectively, compared with the damaged hair. These improvements surpass those achieved by succinic acid （4.47%/13.85%） and citric acid （6.08%/15.85%）, underscoring the critical role of covalent cross-linking. Microscopy further reveals that itaconic acid treatment effectively restores cuticle integrity by mitigating lifting and exfoliation, while protecting against transverse fractures induced by cyclic fatigue stress. Overall, these findings elucidate the targeted repair mechanism of itaconic acid on damaged hair, providing a novel strategy for developing high-performance hair reparatives.

Key words: itaconic acid, hair repair, Michael addition, free sulfhydryl groups, keratin, mechanical properties, hair cuticle

中图分类号:

TQ658

黎曦, 吴雨闻, 成浩楠, 常晓维. 衣康酸靶向修复受损发丝：基于巯基共价键合的力学增强机制[J]. 日用化学工业（中英文）, 2026, 56(6): 783-789.

Xi Li, Yuwen Wu, Haonan Cheng, Xiaowei Chang. Targeted repair of damaged hair by itaconic acid: covalent thioether bonding mechanism for enhanced mechanical strength[J]. China Surfactant Detergent & Cosmetics, 2026, 56(6): 783-789.

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