机构地区: 华南理工大学化学与化工学院化学工程研究所
出 处: 《化学工程》 2005年第6期63-66,共4页
摘 要: 通过实验比较了3种甲苯二异氰酸酯-三羟甲基丙烷(TD I-TMP)预聚物中游离TD I单体分离的工艺,发现采用减压蒸馏和内冷式薄膜蒸发联用的工艺路线,不仅能保证物料在蒸发器系统中有较好的流动性,而且能保证TD I单体蒸气在高真空和刮板的搅动下极易从物料中蒸发出来,最终含量可降低到质量分数0.5%以下。实验还发现高真空内冷式刮膜薄膜蒸发分离预聚物中游离单体的关键因素是物料温度、压力和粘度的控制,它们最适宜的控制范围为:物料温度100—120℃、压力50—150 Pa、粘度500—1500 mPa.s。 Abstract: Three separation technologies of free tolylene diisocyanate (TDI) in TDI-TMP pre-polymer were compared through experiments. The technical process of combination of vacuum distillation and inner condensing thin-film evaporation can assure not only the fluidity of material in evaporator system but also the transferring of TDI vapor from the material under high vacuum and wiping of blades, and the final mass fraction of TDI can decrease to 0.5% below. The experiments also showed that the key factor of free monomer separation from pre-polymer with high vacuum inner condensing thin-film evaporation method is the controlling of material temperature, pressure and viscosity, and the optimum controlling ranges are 100-120℃, 50-150 Pa and 500-1500 mPa·s.
领 域: [化学工程]