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A bismaleimide monomer, 4,4 0 -bis(4-maleimidophenoxy)-3,3 0 ,5,5 0 -tetramethyl biphenyl (BMITB), was synthesized in high yield (94%) via a facile four-step reaction from 2,2 0 ,6,6 0 -tetramethyl-4,4 0 -biphenol. The chemical structure of BMITB was confirmed by FTIR, 1 H NMR, 13 C NMR and elemental analysis. The monomer used to modify the epoxy cresol-formaldehyde novolac resin (ECN)/diaminodiphenyl sulfone (DDS) system. Cured ECN/BMITB/DDS blends with higher BMITB content had two distinct glass transition temperatures that were above 2508C according to differential scanning calorimetry, indicating that an interpenetrated polymer network structure may be formed. The initial thermal decomposition temperature and integral procedure decomposition temperature of the cured ECN/BMITB/ DDS blends were >390 and 10808C, respectively, according to thermogravimetric analyses. No phase separation was observed in dynamic mechanical analysis of cured ECN/BMITB/DDS blends with small amounts of BMITB (5 and 10 wt%).

A new gas sensor was designed based on cataluminescence (CTL) by using catalytic reduction of benzene, toluene and xylene (BTEX) on the surface of nanosized catalyst Al2O3/Pt with hydrogen as the carrier gas. The result indicated that the sensor showed strong CTL response, high selectivity and excellent durability under optimal conditions: Al2O3/Pt (1%), the temperature of 395oC, the wavelength of 425 nm and the flow rate of 270 mL/min. The detection limit (3σ) is 0.2 ppm for benzene, 0.3 ppm for toluene and xylene. Other corresponding substances such as methanol, ethanol, formaldehyde, acetaldehyde, ethylacetate, ammonia and trichloromethane had no or less interference. It is a simple and convenient sensor with good selectivity and sensitivity for detecting BTEX.

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