Non-contact and non-destructive analysis of the quality of phenolic resin by near-infrared spectroscopy

The traditional analytical methods used to determine phenolic resin are slow and produce environmentally unfriendly waste. In this work, near-infrared (NIR) spectroscopy has been applied for resin content of phenolic resins. The partial least-squares regression was used to develop the calibration model of the resin content. Eight samples were withdrawn at different time stages for analysis with the proposed quantitative models; the data thus obtained were compared with those provided by reference methods. The maximal predicted error and the standard deviation of the differences were 0.96% and 0.51% for resin content. The results of the paired t test revealed that there was no significant difference between the NIR method and the reference method. NIR spectroscopy is an effective choice for the accurate, expeditious analyzing quality of phenolic resin.