| Insoluble sulphur (IS) is exclusively vulcanizing agent for production of radial ply tyre . There are many drawbacks in gas phase production of insoluble sulphur at high temperature, such as high energy consumption, great erosion of equipments, explosion and flammability. Contact technology is characteristic of raw material which is extremely limited by environment. In the thesis, adding a variety of new type reagents as stabilizers to the process of reaction for the first time, reaction conditions were investigated in detail when IS was prepared in liquid phase at moderate temperature. Effect of stabilizers and processing oil on thermal stability of IS was studied on the base of IS oil-treated. Influence of reaction conditions on yield of IS was discussed, such as amount of stabilizer, reaction period, reaction temperature, quenching medium and extraction temperature using D-type stabilizer. The results indicated that when amount of stabilizer was 0.8%, reaction temperature was 280℃, reaction period was 70min, yield of IS reached 44%. The ice water as quenching medium was best , and optimum temperature of extraction was under 20℃. The thermal stability of IS could maintain 83.62 %, 79.51%, 89.65 %, and 65.00% at 105℃within 25min when IS was treated by naphthenic oil , paraffinic oil , arene oil and without oil, respectively. For M-type complex stabilizers, the experimental results showed that under amount of stabilizer 0.8%～1.0%, reaction temperature 275℃and reaction time 70min～80min, yield of IS was obtained with 40.95% by it. When amount of stabilizer was 0.55%～0.75%, reaction temperature was 245℃, reaction time was 70min, yield of IS reached 42.31% by F-type complex stabilizer. The performance of F-type was higher than M-type from reaction conditions and yield of IS. The four values of IS prepared by two stabilizers were coincident with the national standards, including degree of acidity, heating decrement, ash and 150μm residue on sieve. Thermal stability of IS treated with arene oil is highest within three processing oils. When two IS prepared by two stabilizers were treated with three processing oils, Thermal stability of IS prepared by F-type stabilizer was higher within same time. Using halide KCl, KBr and KI as stabilizers, reaction conditions, such as amount of stabilizer, reaction temperature and reaction time, were determined by means of single factor method .The experimental results showed that under amount of stabilizer 0.6%, reaction temperature 260℃and reaction time 60min, yield of IS was obtained with 17.09% by KCl. Under amount of stabilizer 0.8%, reaction temperature 280℃and reaction time 90min, yield of IS was achieved with 28.50% by KBr. When amount of stabilizer was 0.6%, reaction temperature was 240℃,and reaction time was 60min, yield of IS was achievable with 29.30% by KI .On the base of thermal stability of IS treated with three processing oil, the combination effects of processing oil types and stabilizers on the thermal stability were compared. Thermal stability of IS treated with arene oil was highest within three processing oil .When IS was treated with same processing oil, Thermal stability of IS prepared with KI was best within three stabilizers. Thermal stability of IS treated with arene oil could maintain 87.51% (KCl),76.32% (KBr),96.00% (KI) in order at 105℃within 15 minutes. On the other hand, the mechanism of processing oil types and halide stabilizer for inhibiting IS reversion was discussed. in detail .
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