Kinetic and Mechanism Studies on Pyrolysis of Printed Circuit Boards in the Absence and Presence of Copper

The kinetic and mechanism of pyrolysis for Cu-free printed circuit board (CFPCB) and Cu-coated printed circuit board (CCPCB) were studied using nonisothermal thermo-gravimetry (TG) analysis coupled with Fourier-transform infrared (FTIR) spectrometry. TG and DTG (differential thermo-gravimetry) analyses were performed to study the mass loss characteristics. Kinetic analysis adopted the Ozawa–Flynn–Wall (OFW) model to confirm the reaction series by the variation pattern of activation energy. The real-time detection technique was used into three-dimensional (3D) FTIR analysis for providing the composition of evolved gases. The results indicated that the pyrolysis reaction of CFPCB can be divided into four separate stages. Stage I (α < 0.075) was ascribed by the breakage of N-containing cross-linkages with low boiling volatiles formed. The irregular cleavage of chemical bonds occurred in Stage II (0.075 < α < 0.85) with the decomposition of both brominated and nonbrominated compounds. In Stage III (0.85 < α <...