Study On Anionic Polymerization And Cyclization Of Farnesene

With dwindling fossil reserves and environmental problems,it is important to develop sustainable bio-based polymers to replace petroleum derivatives.Farnesene,a kind of rich source of long side chain biological terpene monomer,based on which the comb/bottle brush structural polymer is designed and synthesized,is expected to have important applications in rubber,adhesives,lubricating materials,etc.In this paper,farnesenes,olefinic monomer,alkyl lithium as initiator,cyclohexane as solvent,by using the anionic polymerization to synthesize poly olefin,the active polymerization behavior and microstructure is studied,and the method is discussed,and copolymerization of styrene/myrcene,and has carried out three fluorine mesylate catalytic cyclization clustering method,ene/myrcene research.The main research contents and conclusions are as follows:The anion homopolytic behavior of farnesene was studied,and the polymer structure was characterized by gel permeation chromatography and nuclear magnetic resonance spectroscopy.The results showed that the anion polymerization of farnesene was a first order reaction,and the molecular weight increased linearly with the conversion rate.Change regulator types(THF,ETE),proportion,concentration,polymerization temperature can adjust method,material's microstructure,with the increase of regulator polarity or concentration,reduce the temperature,the increase of polymer molecular weight,3,4-Fa structure content increases,the cis 1,4-Fa structure content decrease,trans 1,4-Fa structure content increases,the range between 5.96%-68.83%,87.64%-15.50%,6.42%-20.67%.The anionic copolymerization of farnene with styrene and myrcene was studied.St:Fa(1:1,wt%)copolymers,rl(St)=0.065,r2(Fa)=3.63 in cyclohexane,r1(St)=1.43,r2(Fa)=0.62 in cyclohexane/THF(98:2,vol%);By adding polarity regulator(THF,ETE)and increasing polymerization temperature,the copolymerization activity of styrene was increased from 6.8%,6.8%,13.6%to 19.8%,20.9%,32.7%.The variation trend of 3,4-farnene structure content in the copolymerization reaction with the change of regulator and temperature was similar to that in the homopolymer reaction,and its 3,4-fa structure content varied from 5.14%to 62.24%..Compared with the higher polymerization activity of 2-substituted butadiene derivative-farnesene/myrcene,1,2-substituted basil had higher steric hindrability and no conjugated structure,and neither of them could be initiated by alkyl lithium.Polymyrcene and polyfarnesene,catalyzed by trifluoromesylate,undergo intramolecular cationic cyclization.After cyclization,the carbon-carbon double bond disappears and the hydromechanical volume decreases.The higher the cyclization degree,the smaller the polymer particles.The cyclization rate was up to 100%for 5 minutes at the concentration of t3f(57mmol/L).As the concentration decreased,the cyclization rate decreased.The cyclization rate of polyfarnesene was faster than that of poly myrcene at the same acid concentration.