核磁共振法测定橡胶填充油中的多环芳烃及组成

Content of PAHs and composition of rubber extending oil detected by NMR spectrometer

分别采用核磁共振氢谱和碳谱对不同芳烃含量橡胶填充油进行分析。结果表明:橡胶填充油中的芳烃含量越高,其芳氢率、"湾区氢"(H_(Bay))含量和芳碳率越高;环保型填充油的芳烃组成主要是单环和双环的轻芳烃,其取代烷基的平均碳数较大,而非环保型填充油的芳烃组成主要是多环芳烃,其取代烷基的平均碳数较小;环保型填充油的正构烷碳平均链长均长于非环保型填充油;环保型填充油的支化度高,则正构烷碳平均链长较短,支化度低,则正构烷碳平均链长较长;可通过H_(Bay)含量来评估或预判橡胶填充油潜在的致癌性,但暂无法通过平均核磁共振化学位移来对其潜在的致癌性加以评判。

Proton and carbon nuclear magnetic resonance(1H and 13C NMR)spectrometer were utilized respectively to analyze rubber extending oils in varied contents of polycyclic aromatic hydrocarbons(PAHs).The results show that the higher PAHs in rubber extending oils are,the higher HBay content,ratio of aromatics/hydrogen and aromatics/carbon are.The aromatic hydrocarbons in the environmentally-friendly extending oils are mainly composed of some monocyclic and bicyclic light aromatic components,whose substituted alkyl has more larger average carbon numbers,while the non-environmental extending oils are mainly some PAHs with less average carbon numbers in substituted alkyl.The average length of n-alkyl carbon in the environmentally-friendly extending oils are longer than that of the non-environmental extending oils.For the environmentally-friendly extending oils,the higher the branching degrees are,the shorter the average chain length of n-alkane carbon is,and vice versa.HBay content can be used to assess or predict the potential carcinogenicity of rubber extending oils,but it is not yet possible to judge its potential carcinogenicity by average 13C-NMR chemical shifts.