Tannins are extracted from certain plants and contain numerous phenol groups. They may be employed, together with their derivatives, to formulate protective coatings due to their inhibitive properties. The objective of this research was to synthesize lanthanum “tannates”, to formulate wash-primers. Two “Tara” (Caesalpinia spinosa) tannins and 0.1 M La(NO₃)₃ were employed to obtain the corresponding tannates. The inhibitive action of the tannates was evaluated by linear polarization and corrosion potential measurements employing a SAE 1010 electrode. Lanthanum tannates were used to formulate wash-primers whose anticorrosion performance was evaluated by corrosion potential and ionic resistance measurements. The primers were incorporated in alkyd paint systems and their anticorrosion performance was tested in the salt spray chamber and by electrochemical impedance spectroscopy. Lanthanum tannate primers protected steel and behaved in a similar way to that formulated with zinc tetroxychromate.

中文翻译：

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来自“ Tara”单宁的镧衍生物，用于钢的临时保护

单宁是从某些植物中提取的，并含有许多酚基团。由于它们的抑制性能，它们可以与它们的衍生物一起用于配制保护性涂料。这项研究的目的是合成镧“鞣酸盐”，以配制洗涤底漆。两个“塔拉”（Caesalpinia spinosa）单宁和0.1 M La（NO ₃）₃被用来获得相应的单宁酸。通过使用SAE 1010电极的线性极化和腐蚀电位测量，评估了鞣酸盐的抑制作用。鞣酸镧用于配制洗涤底漆，其耐腐蚀性能通过腐蚀电位和离子电阻的测量来评估。将底漆掺入醇酸涂料体系中，并在盐雾室内和通过电化学阻抗谱测试了它们的防腐性能。鞣酸镧底漆可保护钢，其性能与四铬铬酸锌配方相似。