Hydrochloric Acid Treatment of PA Fibers: Impact on H Bonds and Absorbance of Precipitates

Qualitative and quantitative analysis of fibers play an important role in the current textile industry, especially in the field of materials that are increasingly seeking fiber-reinforced composites; accurate qualitative and quantitative analysis is fundamental work. This work analyzes the dissolution and precipitation mechanisms of polyamide fibers in hydrochloric acid and their key features, which support more precise qualitative and quantitative analysis in relevant domains. By using a spectrophotometer (680 nm) combined with different proportions of chemical reagents, the dissolution and precipitation characteristics of polyamide in hydrochloric acid solution can be accurately characterized. The working curve is constructed based on linear correlation (with a regression coefficient of determination greater than 0.99), enabling accurate quantification . In addition, it was found that this technique has broad applications in the field of criminal investigation (Zughaibi, T. A.; Steiner, R. R. Analysis of Polymeric Carpet Fibers Using Direct Analysis in Real Time Coupled to an AccuTOF Mass Spectrometer. Polymers, 2021, 13, 16, 268−1920. 10.3390/polym13162687.), where it can be applied to the qualitative and quantitative analysis of nanogram samples. It also has the potential to be used in the field of sustainable development.