The Establishment And Validation Of The Method For The Detection Of Regenerated Protein Fiber

Using the regenerated protein fiber as the object, an inspection platform for protein functional fibers was established in this study. As the protein functional fiber has both the characteristics of protein and conventional fiber, the two aspects including the protein to amino acid detection and conventional fiber chemical quantitative analysis were studied in this thesis. On the one hand, the characteristic analysis was done from the molecular level of material by chromatographic technology; on the other hand, the quantitatively, multi-angle multi-level analysis was conducted from the macroscopic point of view, with the final aim of science, reliability and stability.In the first part, the amino acid analysis technology was used to determine the amino acids content in fibers, and to develop a detection method with simple operation, good reproducibility and good stability. The optimized sample pretreatment conditions were also obtained as follows: 6.0 mol/L hydrochloric acid solution concentration, water bath ratio of 1:150, hydrolysis time of 22 hours, hydrolysis temperature of 110 ℃. At the same time, we established amino acid detection method in the concentration of 5.0~100.0 nmol/m L within the scope of the linear correlation coefficient higher than 0.999 with the instrument detection limit of 5 nmol/m L, the relative standard deviation of less than 3.7% for the total amino acid amount of each sample and the experimental precision of standard addition recovery rate over 80.35%. In order to ensure the standardized operation and solve practical problems, an internal standard of GTT TM 033-2013 : the determination of amino acids in textiles was proposed based on the experimental. The comparison verification experimental was carried out with two external agencies and the relative standard deviation of the results was 6.94%, conforming to the standard method of external alignment requirements, which further verifies the effectiveness of the methods established in this paper: the stability, accuracy and feasibility.In the second part, the sort of the regenerated protein fiber was analyzed by using conventional methods, and the results showed that the sort of the regenerated protein fiber can be identified accurately by using the combustion method, microscope observation method, dissolved method and infrared spectrum method, and its chemical dissolving properties were very similar to the matrix fiber. Combining the specific analysis method of amino acids with the common analysis of conventional methods, this project was in accordance with the principles of “Protein and matrix materials dissolved separately” to make the regenerated protein fibers accurately quantified by the chemical dissolution method. Additionally, the mass correction factor of the insoluble fiber was determined by experimental under different conditions.In the final part, through the optimized amino acid analysis, the amino acid content in different kinds of regenerated protein fiber distribution map was built and after the comparison of the amino acid content in the existing literature in various protein fiber characteristics, good agreement has been observed. Therefore, by combining the conventional analysis method of regenerated protein fiber with the content detecting method of amino acid in sample, and then comparing with the amino acid content distribution map of all kinds of regenerated protein fiber, the type of regenerated protein fiber will be determined rapidly. Compared with the conventional methods for the qualitative analysis of regenerated protein fiber, this method is relatively accurate.In this thesis, much work has been done from the appropriate detection equipment recommended, the technology research and development carried out to the complete protein functional textiles testing evaluation system established including the basic database, inspection and evaluation method. The method in this study has filled the blank of detecting the regenerated protein fiber in both qualitative and quantitative standard, and is also effective in solving the current problems concerning more protein functional textile complaints. Furthermore, the detecting method proposed herein provides powerful technical support, standard, regulation and improves the detection mechanism of functional textile detection ability and also brings the obvious social benefits. At the same time, this required equipment investment in this method is small, therefore, with the increasing demanding of the detection to this type of products, once the authoritative testing method is formed, the increasing amount of inspection can also bring considerable economic benefits.In addition, this paper mainly contains two parts of fiber amino acids in the qualitative and quantitative research and chemical dissolved method of quantitative analysis. In the former part, the laboratory configuration an amino acid analyzer was required; while in the latter part, the reagent and equipment in general textile testing lab would be satisfied. Therefore, if the lab has the related equipment configuration, one-time investment would bring long-term and durable benefits. With the development of functional textiles market, more and more green, environmental protection, health new concepts put forward, such textiles functional testing requirements will be more and more demanding. At the same time, as the importance of the detection ability construction is increasing, it can be estimated that the method platform will be gradually popularized and promoted, and finally considerable social and economic benefits will be created.