Synthesis And Properties Of Thermosetting Resins Based On Eugenol

Nowadays,with fear of environmental pollution and shortage of petroleum resources,exploring renewable biomass as alternatives for petrochemical counterparts to prepare polymer materials is essential.And the development of high-performance bio-based thermosetting resin is the current research hotspot.This thesis mainly discuss that using eugenol as raw material to synthesize several polyols via the thiol-ene click reaction.Interestingly,the conversion of the carbon-carbon double bonds(C=C)was almost 100%at the eugenol and various thiol compounds in a stoichiometric ratio without excess of thiol.Then,according to the structural characteristics of polyols,two kinds of eugenol-based thermosetting resins(polyurethane and epoxy resin)with good properties,were designed and prepared.Firstly,eugenol was reacted with a set of mercaptan respectively,including 2-mercaptoethanol(MCH),3-mercapto-1,2-propanediol(MPD),6-mercaptohexanol(HHT)through thiol-ene click reaction,followed by three polyols EUMCH,EUMPD and EUHHT were obtained successfully.The values of conversion rate were calculated according to NMR analysis.In this work,only equivalent mercaptan was needed to achieve nearly 100%conversion of C=C,and complex postprocessing steps were not required.Moreever,the effects of initiator content on the conversion rate and the degree of yellowing of final products were investigated,and the optimal reaction condition was determined.Secondly,the eugenol-based polyols were reacted with diphenylmethane-diisocyanate(MDI),and then series of structure-adjustable thermosetting polyurethane films with excellent properties were designed sucessfully.The thermal and thermomechanical properties of polyurethane films were tested by DSC and DMA analysis,the value of glass transition temperature up to 78.21℃,and their crosslink density could be adjusted by the ratio of several polyols.Mechanical tests,UV-vis and color retention analysis had proved that these polyurethane films had excellent mechanical properties(tensile strength up to 54.88 MPa),colorless transparency,and good color retention.This work might provide a new convenient way to translate eugenol into polyurethane,which would broaden the application of eugenol in the sustainability of the polyurethane industry.Finally,a new eugenol-based trifunctional epoxy resin(TFEP)was synthesized by the "one-pot" method.And the curing reaction kinetics of TFEP with amine curing agents,including polyetheramine(D230),alicyclic amine(H-DDM)and aromatic amine curing agent(DDM),were investigated.The non-isothermal curing kinetics of these three systems was studied by DSC analysis,using model fitting method and Malek criterion.It was found that all three curing systems confirm to the SB(m,n)autocatalytic model,and their reaction rate equation were established accordingly,which could describe the curing reaction well.In addition,the thermomechanical properties of TFEP/D230,TFEP/H-DDM and TFEP/DDM systems were studied by DMA analysis.