Synthesis Of Hexafiuoropropylene Dimer

After a series of reactions,hexafluoropropylene dimer can be fluorinated surfactant and derivatives,pesticides and pharmaceutical intermediates,fire extinguishing products and so on.It can also be used as a reaction solvent under special conditions.With the more and more in-depth study on the hexafluoropropylene dimer,it is showing huge application potentialin the daily life.In this study,hexafluoropropylene dimer was obtained by the oligomerization of six fluorine propylene,and then the two polymer D-1 was converted to a high reactive two polymer D-2 by isomerization.It is found that the best process conditions for the oligomerization are acetonitrile as solvent,KF as catalyst,catalyst concentration of 0.015 mol/L,reaction of 8 h at 50 ?,and the highest conversion rate of six fluorine propylene oligomerization is 75.8%.In the study of D-1 isomerization to D-2,the conversion rate of six fluorpropene was low at high temperature and high pressure by gas-liquid two phase reaction,while the liquid solution was two phase isomerization at medium and low temperature,and the conversion rate of six fluorene could reach 99%.The optimum reaction conditions for high temperature and high pressure reaction process are as follows: 120 mL acetonitrile as solvent,the optimum volume ratio of solvent to D-1 is 1:1.6,KF as catalyst,5 g,30 h at 130 ?,and the final conversion rate of 42.8%.The best conditions for isomerization under atmospheric pressure are: acetonitrile as solvent,KF as catalyst,a concentration of 0.12 mol/L,,0.0375 mol/L,8 h at 48 ?,and a conversion rate of 99%.A preliminary pilot scale study on D-1 isomerization of D-2 was carried out.It was found that acetonitrile was used as solvent and KF was used as catalyst.The conversion rate was 45.2%,10 h at 120 ?,and the final yield was 43.15%.