Preparation And Characterization Of Trans-isoprene Grafted With Maleic Anhydride

Trans 1,4-polyisoprene TPI also called synthetic cortex eucommiae glue,because its orderly microscopic molecular chain structure easy to crystallization,at room temperature with high crystallinity,so at room temperature for the crystallization of hard plastic,has the characteristics of thermoplastic elastomer.The TPI has good tensile,abrasion resistance and wet resistance,and excellent biocompatibility and shape memory,in green tire tread compound materials,medical materials,damping materials,electronics and aerospace has potential application value.However,due to its crystallization at room temperature,high energy consumption during processing and poor compatibility with polar polymers,its application is limited to some extent.Therefore,functional modification of TPI has important theoretical and practical significance.Firstly,graft graft of maleic anhydride(MAH)onto trans polyisoprene(tpi-g-mah)was prepared by solution method.The graft product was characterized by ir and XRD.The structure of graft product was analyzed by NMR.The results showed that the reaction efficiency of DCP induced MAH grafting trans-polyisoprene was higher with the same amount of monomer and initiator.In the solution method,the synthesis of tpi-g-mah is not grafted on the carbon-carbon double bond of TPI,but on the hydrogen atom of-methylene substituted for the carbon-carbon double bond of TPI macromolecular chain.Secondly this paper prepared through melting method with maleic anhydride(MAH)grafted trans polyisoprene(TPI)-g-MAH(TPI),by Fourier transform infrared spectroscopy(FTIR,chemical titration and differential scanning calorimetry(DSC characterization of graft product,grafting reaction mechanism is discussed and studied the dosage of DCP and MAH graft product TPI-g-MAH the influence of physical properties.The results showed that both DCP and BPO were used as initiators to graft the graft product tpi-g-mah.MAH was mainly substituted with hydrogen in TPI and was connected to the TPI macolecular chain.The graft rate of the graft product obtained by DCP was 2 times higher than that by BPO,and the gel content Ge was 2.2 times lower.DSC spectra showed that the tpi-g-mah of grafted products changed from bipeak to unipeak.The melting peak of DSC of grafted products obtained by DCP was narrower and the peak area was smaller than that ofBPO.Compared with pure TPI,the tensile strength of grafted product tpi-g-mah decreased,and with the increase of MAH and DCP dosage,the tensile strength of tpi-g-mah decreased significantly.Finally,the mechanical properties and microstructure of the blends of trans-polyisoprene(TPI)grafted maleic anhydride(MAH)(tpi-g-mah)and cis-isoprene(IR)were studied.The results showed that compared with ungrafted TPI,tpi-g-mah could improve the interfacial compatibility of blends,improve the dispersion of silica and the mechanical properties of vulcanizates,and shorten the curing time of IR blends.