Chitosan microspheres containing bromocresol green, cresol red, and phenolphthalein for corrosion detection, through pH change, are synthesized in order to be used in protective coatings for aluminium alloys. Microspheres containing corrosion detection species are characterized morphologically (SEM) and physico‐chemically (FTIR, TGA). Release studies (UV–vis) are performed in corrosion‐promoting conditions (pH, NaCl), and detection studies by immersion in media associated with corrosion activity while microspheres' sensing activity is evaluated visually. Electrochemical characterization of AA2024 substrates in the presence of chitosan spheres is performed to understand material performance, and a color change is observed as a result of local pH increase in cathodic areas when corrosion takes place. These findings can be correlated with the results from release studies and seem a promising approach for corrosion sensing purposes, not only because pH increase is possible to detect due to corrosion, but also because chitosan is considered an environmentally friendly material.

中文翻译：

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壳聚糖微球作为腐蚀指示中pH指示物种的载体

合成了包含溴甲酚绿，甲酚红和酚酞的壳聚糖微球，用于通过pH值变化进行腐蚀检测，以便用于铝合金保护涂层。包含腐蚀检测物质的微球的形态学（SEM）和理化特性（FTIR，TGA）得以表征。在腐蚀促进条件（pH，NaCl）中进行释放研究（UV-vis），并通过浸入与腐蚀活动相关的介质中来进行检测研究，而目测评估微球的传感活动。为了了解材料的性能，在壳聚糖球存在下对AA2024基板进行了电化学表征，观察到颜色变化是由于腐蚀发生时阴极区域局部pH值升高所致。