Use of a charged coupled device (CCD) camera for evanescent wave optical fiber cure monitoring of liquid composite molding resins

摘要

An optical fiber evanescent wave fluorescence cure sensor described in a previous paper (1) has been interfaced with a fast detector and computer software to provide real-time monitoring of fast-reacting systems. Advantages to the new system include a reduction in data acquisition time (to 200 ms from 3 min), improved time resolution (to 5 sec from 10 min), and improved signal quality. Isothermal cure monitoring measurements were conducted in both distal and evanescent wave sampling modes for an epoxy-amine system. Following a second order background correction, the results for the two sampling modes were identical. Thus the evanescent wave measurement was unable to detect differences between the chemistry in the bulk and at the fiber-resin interface (if there were any differences to observe). The sensor system was also demonstrated for a fast curing (<3 min gel time) polyurethane-isocyanurate system designed for high volume (short cycle time) automotive applications. The system is currently being modified for implementation in a ''real world'' manufacturing environment.