Corrosion monitoring of polymeric materials using optical fiber.

本研究以胺固化型环氧树脂为材料，以BTB和BPB为pH指示剂，通过对含有树脂的pH指示剂在硫酸中的颜色变化进行检测，发现BTB在硫酸和水的双重渗透下颜色发生变化。另一方面，BPB仅通过硫酸的渗透而改变其颜色。通过对含BTB的试样在硫酸中浸泡的横截面的研究，观察到变色层内部的逐渐颜色变化。预计水比硫酸更深地渗透到树脂中，并且通过S元素的EDS图和卡尔费休法的水含量分析证实了该预期。成功地将前人研究的“水的渗透速度快于溶质的渗透速度”的结果可视化， 关于我们 d对材料的渗透有很大的影响。制备含pH指示剂的样本，并将其浸入氯乙酸中。观察到BTB和BPB树脂的颜色变化，并且观察到450-500 nm的透射率降低和600 nm的透射率增加。将光纤置于浸渍在乙烯基酯树脂中的玻璃十字架之间，并固化树脂。然后，在光纤中加工狭缝，并且用含有环氧树脂的pH指示剂填充狭缝。将该传感器埋入玻璃纤维毡中，玻璃纤维毡的一侧与氯乙酸接触。对通过光纤的光的透射率进行监视，从BTB传感器仅观察到500 nm的透射率降低。而BPB传感器在500 nm处的透过率下降，在600 nm处的透过率上升。由此可见，以BPB为pH指示剂的光纤传感器更可靠。少

In this study, the development of sensor detecting the penetration of acidic or alkaline solution into the resin was objected.Amine cured type epoxy resin was used as material and BTB and BPB was used as pH indicator.From the result of examination of the color change of pH indicator containing resin immersed in sulfuric acid, BTB changed its color by penetration of both sulfuric acid and water. On the other hand, BPB changed its color by only the penetration of sulfuric acid. The gradual color change was observed inside of color changed layer by investigation of the cross section of BTB containing specimen immersed in sulfuric acid. It was expected that the water penetrates into the resin further than the sulfuric acid and the expectation was confirmed by the EDS mapping of S element and water content analysis by Karl Fischer method. The visualization of the result of previous study "the water penetrates faster than the solute" was succeeded.After that, the detection of the organic aci … More d, that has a large influence of penetration into the materials, was investigated. The pH indicator containing specimen was manufactured and immersed in chloroacetic acid. Color change was observed both BTB and BPB containing resin and the decrease of transmittance of 450-500 nm and the increase of 600 nm was observed.Next, the thin optical fiber sensor enable to apply between the layer of FRP was manufactured. The optical fiber was put between glass cross impregnated in vinyl ester resin and the resin was cured. Then, the slit was machined in optical fiber and the slit was filled with pH indicator containing epoxy resin. This sensor was embedded in glass mat type FRP and one side of FRP was contacted to chloroacetic acid. The transmittance of the light passing the optical fiber was monitored.From the BTB sensor, only the decrease of the transmittance of 500 nm was observed. On the other hand, BPB sensor had both the decrease of transmittance of 500 nm and the increase of 600 nm. From this result, it can be said that optical fiber sensor using BPB as pH indicator is more trustful. Less