On-line monitoring of resin content for film impregnation process

Process Monitoring of Polymer Systems by using Near-Infrared Spectroscopy

“…Traditional analysis methods such as solvent extraction, burn-off and acid digestion are often used to measure the three factors. However, these methods are unsuitable for continuous measurement during the manufacture of prepregs due to the excessive time required and the destructive analysis of the specimen (Huang et al, 1997). So far, a series of process monitoring techniques have been developed to measure the prepregs quality.…”

“…-ray transmission technique (Huang et al, 1997;Huang et al, 2003) The theoretical basis of -ray montioring the prepreg quality is that the energy is attenuated during the penetration of the prepreg by -particles. The attenuation of transmitted radiation is related to the thickness of prepreg:…”

“…Because the resin content is related to the prepreg thickness, the resin content is obtained by determining the thickness. Fig.2 is the schematic of monitoring resin content of prepreg by -ray technique (Huang et al, 1997). The prepreg specimen was passed through the middle between the -ray source and the detector.…”

“…Finally, the unknown specimen was determined according to the above relationship. The studies indicated that the -ray technique always holded high accuracy in determining the resin content with broad range (Huang et al, 1997;Huang et al, 2003). With the nature of rapid and non-contact features, the -ray technique can be used in the product line to continuously monitor the resin content of prepreg.…”

Rapid and nondestructive analysis of quality of prepreg cloth by near-infrared spectroscopy

“…Recently, a series of investigations on the analysis of the quality of the prepreg have been carried out in succession, in which the methods utilized include the c-ray reflectance [1], ultrasonics [2,3], photometry [4,5], b-ray transmission [6,7] and infrared spectroscopy (IR) [8] techniques. Although these methods overcome most shortcomings accompanied with the traditional analysis methods, they cannot monitor the three factors at the same time.…”