The nonliquidphase coordination crosslinking reaction of acrylonitrilebutadiene rubber/copper sulfate(NBR/CuSO4) mixture was investigated by differential sanning calorimetry (DSC)

Fourier transform infrared (FT-IR) spectrometry and X-ray photoelectron spectroscopy (XPS).The NBR/CuSO4 mixture specimens for DSC and FT-IR were prepared in an open two-roll mill at room temperature by blending NBR (100 phr) and CuSO4 powders (10

20 and 30 phr

respectively).Specimens for XPS test were prepared by molding NBR/CuSO4 mixtures at 120

170

190 and 200℃ for 20 min.DSC results showed that pure NBR was thermostable and inert between 150℃ and 270℃

while the curves of NBR/CuSO4 mixtures presented three thermo positive peaks in the temperature range from 150℃ to 330℃.FT-IR spectrometry indicated that the polymer structure of the specimens maintained without noticeable alteration at temperatures below 200℃.It means there were no oxidations or other exothermal reactions except for the probable coordination reaction between —CN and Cu2+.N1s XPS spectrum of NBR/CuSO4 mixtures only displayed a single peak with a binding energy of 399.1 eV belonging to free —CN at lower temperature(120℃)

while fitting N1s spectrum gave two secondary peaks at 399.2 eV and 401.3 eV at the test temperature of 170℃

190℃ and 200℃

and the latter was attributed to coordinated —CN.It bore out that the coordination reaction of —CN and Cu2+carried out well and truly.Moreover

it was confirmed that the first thermo positive peak of DSC was attributed to the coordination crosslinking reaction of —CN and Cu2+in the non-liquid-phase mixture.The apparent activation energy and reaction order of the non-liquidphase coordination crosslinking reaction were evaluated by Kissinger method and Crane equation.With CuSO4 content of 10，20 and 30 phr the results of apparent activation energy were 86.22

85.89 and 83.98 kJ/mol，and the reaction orders were around 0.9.