Determination of Moisture Content of Polyamide 66 Directly from Combination Region Near-Infrared Spectra

作者：Kuda Malwathumullage Chamathca P S; Small Gary W^*

来源：Journal of Applied Polymer Science, 2014, 131(16): 40645.

DOI：10.1002/app.40645

• optical properties
• sensors and actuators
• spectroscopy

The hygroscopic nature of polyamide (PA) polymers motivates the development of analysis tools for use in assessing their moisture content. Among possible analysis techniques, near-infrared (near-IR) spectroscopy is non-destructive, requires little or no sample preparation, and is compatible with sample thicknesses on the order of mm. The work reported here makes use of transmission near-IR spectroscopy in the combination region (5000-4000 cm(-1)) to develop a protocol for assessing the moisture content of PA 66 samples directly from their spectral intensities after preprocessing with the standard normal variate transform and partial least-squares. The method is compatible with online or continuous monitoring applications and can be calibrated without the use of destructive reference measurements such as thermogravimetric analysis. The long-term calibration performance of the technique is evaluated, and on a scale of 0-100% moisture uptake, the standard error of prediction is found to average 1.4% over 6 months.

• 出版日期2014-8-15