Synthesis Of Ionic Liquids And The Application In The Preparation Of Polyketone

Polyketone prepared by the copolymerization of carbon monoxide(CO) and styrene(ST) has good mechanical properties especially photodegradability which has caused widespread concern as a new type of environmentally friendly material. But its expensive price of catalyst constrained progress of the research. In this paper several ionic liquids as solvent for palladium-catalyzed copolymerization of carbon monoxide and styrene were prepared under microwave irradiation. The traditional solvent was replaced by ionic liquid for the recycling of catalyst in order to achieve lower product costs purpose.Room temperature ionic liquid 1-butyl-3-methypyridinium hexafluorophosphate as solvent for palladium-catalyzed copolymerization of carbon monoxide and styrene was prepared by the reaction of 4-methypyridinium, bromobutane and kalium hexafluorophosphate under microwave irradiation. Ionic liquid and copolymer were characterized by elemental analysis, differential scanning DSC, TG, GPC, XPS, 1HNMR and IR. The different palladium catalysts, amount of ionic liquid, amount of palladium composite catalyst, reaction time and the reusability of catalyst-ionic liquid system were discussed. It indicated that the yield of polyketone and the catalytic activity in ionic liquid systems were enhanced over conventional solvent under similar conditions. The highest catalytic activity was 414g/(gPd·h) when reaching optimum conditions. It was also found that of composite catalyst in ionic liquids still kept 51% catalytic activity after 4 successive recycles.Eleven ionic liquids as solvent for palladium-catalyzed copolymerization of carbon monoxide and styrene were prepared under microwave irradiation. The process of traditional and microwave methods were compared. The effect of microwave power on preparation of ionic liquids was studied. The influence of different kinds of ionic liquids on the reaction was investigated. The application of butyl pyridine hexafluorophosphate ionic liquid in polyketone and the reuse of catalytic system were studied primary. Results indicated that the reaction time was shorten significantly and yield was improved by microwave method. The catalytic effect was better by using pyridine [PF6]- ionic liquids. The highest catalytic activity was 1343g/(gPd·h) when reaching optimum conditions using butyl pyridine hexafluorophosphate ionic liquid. It was also found that of composite catalyst in ionic liquids still kept catalytic activity after 4 recycles.