The Preparation,Characterization And Application Of Latex Of Polyisoprene Catalyzed By Rare Earth

This article mainly discussed the formulation of emulsifiers and preparation process of latex of polyisoprene catalyzed by rare earth.At first through the study and optimization of different emulsifiers' system and we determined the best emulsifier formulation.Then we optimized the technology of latex preparation and prepared the latex with the best comprehensive properties.Finally,we explored the mechanical properties of the homemade IRL.1?The formulation of the emulsification : The concentration of oil phase is 8% and the oil/water mass ratio is 1:1.The main emulsifiers adopt disproportionated rosin acid potassium and SDBS and the composited ratio of them is 2:1 and the dosage is 3% of aqueous phase.The co-emulsifier adopt Span80 and the dosage is 0.2%~0.3% of aqueous phase.The stabilizer adopt PEG-6000 and the dosage is 0.05% of aqueous phase.The p H of aqueous phase is 12.The average particle size of latex is about 300 nm.2?When the concentration of oil phase and oil/water mass ratio at different situations,we should determine the dosage of the main emulsifier on the basis of 37.5% of the dissolved rubber.The main emulsifier adopt disproportionated rosin acid potassium and SDBS and the composited ratio is always 2:1.3?Oil phase prepared under the conditions at 60 ?,stirring speed during the 700-800 r/min for 24 hours.Oil phase continuously added to the water in the emulsion process.Homogenize the system at 6000 r/min for 10 minutes.4?During the distillation process,we adopt atmospheric distillation and magneton stirring method.The stirring speed control between 200~300 r/min and distillation temperature controlled at 78 ? ~80 ?,the quantity of foams and distillation demulsification rate are low.5?We adopt centrifuge during the concentration process and the speed of centrifugal is 8000 r/min for 10 min,the solid content of centrifugal latex is 63.89%.During this process increasing the centrifugal rotational speed and prolong the centrifugal time can achieve the same effect.Average particle size of the centrifugal latex is about 500 nm.6?During the process of preparation film,drying process is divided into three stages,fast followed by slow.The time of storage will influence the performance of the latex mechanics.