利用比色法研究丝绸的老化

利用比色法测量经光或热老化后，丝纤维中[NH3]和[-NH2]的含量，由此推断出导致丝织品老化的主要因素是氧化作用还是水解作用。为研究古代丝织品的保护、改善丝织品的保存环境提供依据。分析结果表明年代久的样品中[NH3]和[-NH2]的含量较高。

Study on silk aging through colorimetry

The effect of Ultra violet (UV) and heat on silk has been discussed. With Colorimetry in measuring [NH3] and [-NH2] of silk fibre irradiated by UV or heated, it can be identified that the main factor leading to silk aging is UV and heat or hydrolysis which makes the protine macromolecules of silk fibre degraded. This can provide a basis for studying the conservation of anclent silk and improving the condition of conservation of silk. This work is proceeded on the assume that the quantity of amino-group on the end of a chain or on the branched chain of the macromolecules of silk fibre is certain, and that if the quantity increases, it means that the macromolecules degrade. The changing of [NH2] or [NH3] is tiny. So, a good calibration curve must be set up for measuring precisely [NH3] or [-NH2]. Two curves are merged into one by regression analysis, which minifies error and elevates the precision of analysis. Several samples heated or irradiated by (UV) have been analysed. The result is shown that [NH3] is increasing with the time of heating or irradiating increasing. Several ancient samples have also been analyzed, The result is shown that the older the ancient sample, the higher the amount of [NH3] and [-NH2].It .means that the extent of damaging of ancient fabrics increases with the time increasing.