【摘要】 用1H NMR谱,13C NMR谱,二维谱,X-射线衍射等方法研究了镍系高顺式聚丁二烯橡胶(NiBR)在强紫外(UV)光辐照前后的微观结构变化和分子运动情况.分析表明NiBR样品随着UV光辐照时间的增加,侧链乙烯基端基双键比主链端基双键更易发生氧化反应;并且随着NiBR样品的各基团的半峰宽值逐渐增加,表明NiBR在UV辐照过程中发生了部分交联反应.样品的X-射线衍射谱图中结晶峰强度随UV光辐照时间的增加逐渐降低,表明样品的晶形无序程度增加了.自旋-晶格弛豫时间(T1)和自旋-自旋弛豫时间(T2)值给出了有关NiBR辐照前后分子运动变化的信息.更多还原

【Abstract】 The effects of UV irradiation on high cis-1,4-polybutadiene (NiBR) were studied by 1D and 2D NMR spectroscopy,1H relaxation time measurements and X-ray diffraction. The results indicated that,with the increase of UV irradiation time,oxidation reaction takes place more often in the side vinyl group terminated of polybutadiene than in the double bonds terminated in the main chain. Moreover,the increase of the half-width of the peaks upon irradiation indicated that the crosslinking reaction had occurred. The X-ray diffraction data showed that the intensity of the crystallization peak decreased with the increase of UV irradiation time. This indicated that the crystal content of the sample was reduced by UV irradiation. The changes in 1H relaxation times provided important insight into the effects of irradiation on molecular segmental motion in the polymer.更多还原