Design,Synthesis And Application Of New Bio-based Itaconate Oil-resistant Elastomer

With the improvement of automobile fuel efficiency,the upgrade of fuel injection system and the miniaturization of the body,oil-resistant elastomers need to maintain stable performance in a wider temperature range and a more complex liquid environment,which requires new materials for oil-resistant elastomers.In addition,the monomers used to prepare existing oil-resistant elastomers,such as acrylates and acrylonitrile,mainly come from non-renewable petrochemical resources.In order to maintain the sustainable development of the rubber industry,we have carried out research on the use of biomass resources to prepare oil-resistant elastomers.The diester group of the itaconate monomer can provide the polar groups needed for oil-resistant rubber.In this project,itaconic ester and acrylate were used as the main raw materials to prepare the bio-based itaconate oil-resistant elastomer and its compound Materials,the contribution of different ester-based components to oil resistance was investigated,which provided ideas for the high performance of bio-based oil-resistant elastomers.The first part of this paper is based on poly(dibutyl itaconate/butyl acrylate)(PDBB)based on dibutyl itaconate(DBI)and butyl acrylate(BA)through redox emulsion polymerization,the orthogonal test was designed and the formulation was optimized:3wt%emulsifier dosage,0.05wt%initiator dosage,reaction temperature 30?,reaction time 8h.Introduced glycidyl methacrylate(GMA)as a functional group monomer,designed and synthesized(poly(dibutyl itaconate/butyl acrylate/glycidyl methacrylate)(PDBBG)and its composite material PDBBG/CB,With the increase of DBI,the oil resistance of PDBBG/CB has been improved to a certain extent,but it still fails to meet the requirements for use and needs to be improved.In the second part of this paper,we replaced the main monomer DBI with diethyl itaconate(DEI)with a shorter side chain,and designed and synthesized poly(diethyl itaconate/butyl acrylate/glycidyl methacrylate)(PDEBG)with different monomer ratios.Its number average molecular weight is between 134000 and 360000.With the increase of DEI content,Tg is between-41.9? and 1.7?,and gradually increases.The tensile strength of the composite material PDEBG/CB can reach 12.1 MPa,and the elongation at break can reach 127%.With the increase of DEI content,the oil resistance gradually improves,indicating that itaconic ester oil-resistant rubber with higher bio-based content has better application prospects.In the third part of this paper,we used short side chain ethyl acrylate(EA)instead of part of the DEI to design and synthesize a new oil-resistant elastomer poly(diethyl itaconate/butyl acrylate/ethyl acrylate/Glycidyl methacrylate)(PDEBEG).Its number average molecular weight is greater than 200,000,and the conversion rate can reach 96%.With the increase of DEI content,Tg gradually increases between-25.2? and-0.8?,and has good thermal stability.As the DEI content increases and the dispersion improves,the tensile strength of the composite material PDEBEG/CB can reach 14.5 MPa and the elongation at break can reach 305%.In addition,we studied the oil resistance of PDEBEG/CB with different monomer ratio The results show that the high temperature oil resistance of PDEBEG/CB with DEI content of 10wt%and 20wt%is better than that of commercially available acrylic rubber AR72LS.