It was also found that the decrease of immersion resistance and impedance of the commercial anti-corrosion of poly ( vinyl chloride co-isobutyl vinyl ether ) coating with increase of directly adding of nano-TiO2, which was elucidated with the theory of critical pigment volume concentration ( CPVC ). 直接添加纳米二氧化钛的商品化防腐涂层耐浸泡性能和交流阻抗值随添加量增加而降低,利用临界体积浓度(CPVC)理论等解释了该现象;