| Bio-based thermosetting resin is attracting more and more attention with the deep research on biobased polymer materials.The biobased thermosetting with high-performance,functional and applicable were synthesised by choosing suitable bio-based platform compounds,designing and regulating molecular structure.It is also conformed to the concept of sustainable development of the future society.In this study,the renewable myrcene and its derivatives were used as the raw materials to synthesis a series of epoxy resin,epoxy curing agent and vinyl ester resin by the Diels-Alder reaction,esterification of congugated double bonds,hydroxyl group,Michael addition etc.Then the natural oils,such as castor oil,tung oil and epoxy fatty acid methyl ester were used to modify the myrcene-based polymer materials.And the copolymers with high reactivity,rigid and flexible combined,excellent comprehensive performance were prepared.The relationship between their structure and performance is also discussed.This work offerd theoretical references and basis for the utilization of myrcene and plant oils in area of epoxy resin and the vinyl ester resin.The main research work includes the following five parts:1.Myrcene maleic anhydride adduct(MMY)was synthesised by using the D-A reaction between myrcene and maleic anhydride.Then it was used as the curing agent for epoxy E-51.The tensile strength and modulus of the cured products were high,while the impact property was poor.Therefore,ricinoleic acid containing long fatty acid was used to modify the myrcene maleic anhydride adduct(CMMY).The flexibility of the pure CMMY cured epoxy was high while the strength was poor.Thus,the two curing agents were mixed by different weight ratios and were used as the curing agent for epoxy E-51 to obtain materials with high strength and flexibility.The chemical structure of the phosphorus containing curing agent were characterized by FTIR and ~1HNMR.Properties of the cured products were tested by Universal Tester,impact tester,DMA,DSC and TG.Results indicated that the comprehensive properties were better when the weight of MMY/CMMY was 25/75.The tensile strength,impact strength,elongation at break,glass transition temperature and initial degradation temperature were 11.11 MPa,62.51 Mpa,259.43 %,45.09 oC and373.90 oC,respectively.2.Phosphorus-containing anhydride epoxy curing agent(MMDOPO)was prepared by introducing DOPO to the myrcene maleic anhydride adduct and it was used as the curing agent for epoxy E-51.The cured material was brittle due to the existence of alicyclic ring and P-phenanthrene.Then another organophosphorus-containing castor-oil-derived diacid(MAPDGR)was synthesized from the reaction of ricinoleic acid with epichlorohydrin,dibutyl phosphate and maleic anhydride.The glass transition temperature and strength were low because of the presence of long aliphatic chain in ricinoleic acid.Therefore,the two curing agents were mixed with at different weight ratios and used as the curing agent for epoxy E-51.The properties of the cured products were also tested.The chemical structure of the phosphorus containing curing agent were characterized by FTIR and ~1HNMR.Properties of different cured samples were tested.Results indicated that when MMDOPO/MAPDGR was 25/75,the tensile strength was moderate and elongation at break was high and they were 9.95 MPa and160.8%.Glass transition temperature rised from 13.41 oC to 100.26 oC.The limit oxygen index was improved to 24.5.3.Novel myrcene-derived epoxy resin was synthesized by using the myrcene maleic anhydride as the raw material.Then it was cured with three different curing agent,methyl nadic anhydride(MNA),diethylenetriamine(DEA)and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane(KH792).The properties of the cured products were tested separately.The curing kinetics of the samples cured with MNA and DEA were investigated and the effects of siloxane group on the properties of the cured product were also discussed.Results indicated that EMMY/MNA was rigid material with high strength,and tensile strength and elongation at break was 39.31 Mpa and 4.24%,respectively.EMMY/DEA was toughness material with moderate strength,and tensile strength and elongation at break was 16.27 Mpa and 51.80%,respectively.EMMY/KH792 can cured at moist atmosphere,the char yield of it was 16.40%,which is higher than EMMY/MNA and MMY/DEA(11.56 and 5.94%).Glass transition temperatur of EMMY/MNA,EMMY/DEA,and EMMY/KH792 were 67.67 oC,64.42 oC,and 69.15 oC.4.Poly-fatty acid-derived epoxy resin(EPFA)was prepared via the condensation reaction and esterification of epoxidized fatty acid methyl ester and the epichlorohydrin.The flexibility of the epoxy resin was good because of the existence of long fatty acid,ether bond and low epoxy value.Then we mixed the prepared epoxy with the myrcene-derived epoxy resin(EMMY)at different weight ratios to obtain the copolymers of the two different resins.The myrcene-derived epoxy resin was toughened and the properties of the copolymer were tested.The relationship between structure and property of the cured products were also discussed.The chemical structure of EPFA were confirmed by FTIR and ~1HNMR.With the increasing content of EMMY,the Tgs of cured products were rised from 17.12 oC to73.29 oC and tensile strength rised from 0.85 MPa to 39.31 MPa.When the content of EMMY was 50~75 wt%,glass transition temperature,tensile strength and elongation at break were between 53.97-63.38 oC,9.57~15.96 MPa and 32.3~161.47%.5.Novel ultraviolet(UV)-curable vinyl ester resin(VER)monomers derived from myrcene(ADMM)was synthesized via Diels-Alder reaction,glycidylation reaction and ring-opening esterification.The tensile strength and modulus of the cured products were high as the high crosslink desity and alicyclic structure,while the impact property was poor.Therefore,another ultraviolet(UV)-curable vinyl ester resin(VER)monomers derived from tung oil(TOA-GMA)was synthesized.The pure tung oil based vinyl ester resin was flexible because of the presence of plenty of long fatty acid chains.Then we mixed the two UV-curable VER with different weight ratios to prepared materials combined with high strength and good flexiblility.The properties,curing behaviors and relationship between structure and properties of the cured products were also studied.Results indicated that the final double bond conversition of all copolymers were above 90%,thermal stability analysis indicated that initial degradation temperature of all cured products were above 388 oC.Mechanical properties test indicated that with the increasement of EMMY,tensile strength and modulus were increased,while flexural modulus and elongation at break first increased then decreased.When the weight ratio of ADMM was between 60~70%,tesile strength and elongation at break were between 28.4~33.9Mpa and 10.9 ~8.1%,respectively. |
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