| Rubber is a kind of insulative material, but when its surface static electricity accu-mulates to a certain quantity, the discharge of electric spark plays a high risk for security.Hereby, the study on antistatic rubber have received extensive concern. On the otherhand, numerous researches concerning solid polymer electrolyte have been reported inrecent years. Nitrile rubber (NBR) is non-crystalline material with low glass transitiontemperature, high ?exibility and excellent elasticity, and its nitrile groups ( CN) pos-sess high polarity and electron donating nature. All of these characteristics well meetthe requirements that needed to act as a successful matrix for polymer electrolyte. Inthis thesis, lithium salts were used to modify the electrical properties of NBR. The anti-static properties of NBR/LiAA composite and the conductivity of NBR/LiClO4 compos-ite were investigated, and the relationship between morphology and electrical propertiesof NBR/lithium salts was revealed.Firstly, the in situ preparation of lithium acrylate (LiAA) in NBR decreased thespeci?c volume resistivity ( v) from 1012Ωcm to 7:05 1010Ωcm with the LiAAcontent of 50phr, contributing antistatic property to NBR. At the same time, the cur-ing rate, curing degree, mechanical properties and thermal stability of NBR were alsoimproved. The coordination between CN and Li+ favored the dissolution of LiAA inNBR matrix, and thus v of NBR/LiAA composite was decreased. The lanthanum chlo-ride (LaCl3) was used to further decrease the v of NBR/LiAA composite. The v ofNBR/LiAA/LaCl3 composite decreased with increasing LaCl3 content and reached theminimum value (2:48 108Ωcm) at the LaCl3 content of 20phr. The curing rate, cur-ing degree, mechanical properties and thermal stability of NBR/LiAA/LaCl3 compositewere all much better than those of NBR/LiAA composite.Secondly, solid polymer electrolyte based on NBR and LiClO4 were prepared bysolution blending process. The effect of CN/LiClO4 mole ratio on the conductivityof NBR/LiClO4 composite was investigated. The maximum conductivity of 1:2110 4 S cm 1 was achieved in the NBR/LiClO4 composite at the CN/LiClO4 mole ratioof 1/2.5, which was in accordance with the maximal number of Li+ coordination with CN, indicated by Fourier transform infrared spectrometry (FTIR) measurement.Then, the electrolyte matrix used was further expanded to NBR/epoxy resin blend.The conductivity was further increased by 2 3 times when 30phr epoxy resin was in-troduced into NBR. Field emission scanning electron microscopy (FESEM) and atomicforce microscopy (AFM)characterization showed that epoxy resin signi?cantly improvedthe dispersion of LiClO4, leading to better surface smoothness of NBR/epoxy resin/LiClO4 composite ?lm. X-ray diffraction (XRD)analysis showed the destruction of crys-tal structure of LiClO4 in NBR/epoxy resin matrix, indicating the better dissolution ofLiClO4. FTIR analysis indicated the addition of epoxy resin increased the free Li+ incomposite. All of these factors contributed to the increase of conductivity.Next, ionic liquid 1-butyl-3-methylimidazolium tri?uoromethanesulfonate (BMI-MOTF) was introduced into NBR/epoxy resin/LiClO4 composite, with the LiClO4/BMI-MOTF mole ratio of 1/0.54. The addition of BMIMOTF could further improve the con-ductivity. The conductivity of NBR/epoxy resin/LiClO4/BMIMOTF composite couldretain around the maximum value even at high LiClO4 content. Infrared difference spec-troscopy and nuclear magnetic resonance spectroscopy (NMR) analysis con?rmed theinteraction between LiClO4 and BMIMOTF, which cause a decreasing interaction be-tween CN and Li+, results in the increase of free Li+, and plays an important role inthe enhancement of conductivity. FESEM and XRD analysis indicated BMIMOTF im-proved the dissolution of LiClO4 and contributed to the increase of conductivity.
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