Synthesis And Properties Of Perilla Oil-based Epoxy Resin

Low-carbon and environmentally friendly materials are attracting widespread attention.Vegetable oil has a wide range of sources and low prices.The flexible long chains and special groups contained in it can toughen and modify epoxy resins,and can maintain the excellent mechanical properties,chemical resistance and dimensional stability of epoxy resins.At the same time,the disadvantages of high brittleness and low impact strength are effectively improved.High-purity perilla alpha-linolenic acid ethyl ester has good health care effects,however,a large amount of fatty acid ethyl ester is produced as a by-product during processing.In this study,the by-products generated during the purification and processing of perilla alphalinolenic acid ethyl ester were used as the basic raw materials,the epoxidation modification and curing process were studied,the properties of the cured products were determined,and the effect of perilla cellulose addition on the properties of the products was investigated.The research results could provide technical support for the comprehensive processing and utilization of perilla renewable resources.The main results were as follows:(1)The epoxidation process conditions of recovered perilla oil were optimized.On the basis of single factor experiment,the addition amount of hydrogen peroxide,formic acid addition and reaction temperature were selected as the main influencing factors,and the epoxidation process conditions of recovered perilla oil were optimized by response surface design.The optimum process conditions were determined as follows: the amount of hydrogen peroxide added was80.90wt%,the amount of formic acid added was 45.6wt%,the reaction temperature was 50°C,and the reaction time was 2.5 h.Under these experimental conditions,the epoxy value of the perilla oil-based epoxidation product could be reached 6.70%.(2)The curing reaction conditions of perilla oil-based epoxidized resin were studied,and the properties of the product were determined.Using methylhexahydrophthalic anhydride as the curing agent and 2-methylimidazole as the accelerator,the curing reaction was carried out at high temperature.When the curing agent content was 70wt%,the tensile strength and tensile elastic modulus of the cured product were the highest respectively 49.69 MPa and 956.79 MPa.And the extrapolated starting point of the thermogravimetric curve of the cured product was308.34°C to 322.91°C,which had good high temperature resistance;the maximum shore hardness of the cured product was 80.4 HD,and its chemical resistance was still good performance.(3)The study investigated the effect of perilla straw cellulose addition on the curing properties of perilla oil-based epoxidized resin.The tensile test results showed that after adding 0.75wt%perilla cellulose,the maximum tensile strength and tensile elastic modulus of the cured product reached 59.57 MPa and 1278.28 MPa,which were 19.88% and 33.60% higher than those of the control group,respectively.The addition of cellulose could effectively improve the tensile properties of the cured product.Different additions of perilla straw cellulose had little effect on the thermal stability,shore hardness and chemical resistance of the cured product.