| Traditional epoxy resin mainly comes from petroleum and its derivatives,but the nonrenewable fossil fuels and the pressure on the environment make the development of biodegradable materials more and more important.Due to many distinct characteristics of wide source,low cost and biodegradability,the vegetable oil has been considered as one of the ideal raw materials for the production of biomass based epoxy resin to meet the development requirements of green chemistry.Epoxidized vegetable oil has many properties of traditional petroleum based epoxy resin.It has a good application prospect,but the low reaction activity of internal epoxy group of epoxidation vegetable oil has limited its application scope in the materials possessing because of lacking hardness,strength.Therefore,the study of biomass based epoxy resin with terminal epoxides has aroused interest in the scientific community.In this paper,we employ the fatty acid oleic acid（OA）as the raw material,which mainly derives from the hydrolysis of glyceride in animals and vegetable oils,and is a renewable natural resource in nature,to produce biomass based epoxy resin epoxidized glycidyl oleate（EGO）.And the performance of the epoxy resin is studied in details.The main contents are listed as follows:First of all,OA and epoxy chloropropane（ECH）were employed as raw material,while triethyl benzyl chloride（TEBAC）and NaOH were used as catalysts.The conditions of synthetic of oleic acid-2-hydroxy-3-chlorpropyl ester and glycidyl oleate（GO）were optimized by single factor experiment.The epoxy value and yield of the two-step reaction product GO were the criterion for judging the reaction.And the obtained products were characterized using FTIR,NMR and MS.the optimum conditions for esterification reaction is reaction time 5 h,ECH:OA=10:1（mole ratio）,reaction temperature 105℃,TEBAC:OA=0.005:1（mole ratio）;The most suitable closed-loop conditions is reaction time 10 h,NaOH:OA=1:1（mole ratio）,reaction temperature 50℃,under the optimum conditions,the epoxy value of GO is 0.289mol/100g,and the yield is 88.71%.Secondly,the epoxidation reaction was carried out with GO as raw material and two different types of catalysts,chloroxybenzoic acid（MCPBA）and methyl trioxide（MTO）respectively.The conditions of epoxidation were optimized by means of single factor experiment and orthogonal experiment.The best reaction conditions for the MCPBA catalyst are determied as reaction temperature 30℃,MCPBA:GO=2:1（mole ratio）,reaction time 2 h,and under the condition,epoxy value of EGO is 0.514 mol/100g.The best reaction conditions for MTO as catalyst is MTO:GO=0.001:1（mole ratio）,reaction temperature 15℃,H2O2:GO=2.5:1（mole ratio）,3-MePz:GO=0.1:1（molar ratio）,reaction time is 4 h,and under the condition,the epoxy value of EGO is 0.536 mol/100g.Comparison of the catalytic effect of two kinds of catalysts,the system of MTO as catalyst is a solvent free reaction without organic acid,with H2O2 as the oxidant,only a byproduct of water,and hence the pollution is small.In addition,the reaction activity of the MTO as catalyst is higher,the reaction condition is mild,the dosage is less,the epoxy value of the product is higher,and the product is easy to separate.At last,EGO as raw material,two kinds of acid anhydride curing agents of MeHHPA and HHPA,and the wo imidazole catalysts of 1-MI and 2-MI,were chosen to set up curing systems.There were 4 big curing systems containing 12 curing experiments.The curing mechanism of the polymer produced were composed by both esterification and etherification occurring during the curing process.The initial decomposition temperature of the polymer is 300-315℃.The dielectric constant of the EGO/HHPA/2-MI1%curing system is minimal（at 1 MHz is 2.50）.The dielectric loss of the EGO/MeHHPA/2-MI3%curing system is the smallest（at 1 MHz is0.0139）.EGO/HHPA/1-MI1%is the highest resistance to electrical breakdown in all systems,which was up to 22.96 kV/mm.Under the normal condition,the tensile strength is 2.87 MPa,and the elongation at break is up to 66.25%. |
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