CURE BEHAVIOR OF PAPER PHENOLIC COMPOSITE SYSTEMS - ASSESSMENT OF THEPROGRESS OF CURE BY DIFFERENTIAL SCANNING CALORIMETRY

The cure behavior of phenolic-resin-impregnated kraft paper composites was studied by differential scanning calorimetry under dynamic and is othermal modes of operation. Procedures for establishing baselines, pr ogress of cure, and fractional conversions as a function of time or te mperature are presented. In dynamic experiments, the cure process was monitored up to 525 K In isothermal experiments, curing was conducted at 430 K, 440 K 450 K, 460 K, and 470 K Heating rates were in the rang e 5-40 K/min. The exothermic heat of cure was found to be about 740 kJ /kg resin from both the dynamic and isothermal experiments. Results fo r isothermal experiments were adjusted to account for differences in t he residual heat of cure at temperatures below 525 K