热压条件下绿色柯巴树脂的聚化行为及^13C NMR表征

人工热压处理有助于天然柯巴树脂聚化,使其萜烯类侧链上的共轭双键断键,可转变为具一定商业意义的绿色、黄绿色、深橙黄色及黑色柯巴树脂。采用SEM,FTIR,^13C NMR等分析测试方法对热压处理前、后柯巴树脂样品的微结构、红外吸收光谱、^13C NMR共振谱进行了研究与分析。结果表明,热压处理可导致柯巴树脂样品中的初级胶粒相互聚合,形成尺度约为180～210 nm的次级异形微球胶粒,微球胶粒聚合体呈无序分布,彼此间形成良好的界面结合;位于3 077（νC-H）,1 643（νC=C）,889 cm^-1（νC-H）处的红外吸收谱带以及δ=15.8×10-6,82.0×10-6,108.0×10^-6,215.1×10^-6化学位移^13C NMR共振谱峰逐渐消失,由此派生的δ=135×10^-6～13^7×10-6和δ=33.9×10^-6化学位移13C NMR共振谱峰则具重要的鉴定意义。

Polymerization Behavior and ^13C NMR Representation of Green Copal Resins under Heat-Pressurized Process

The artificial heat-pressurized treatment is contributed to the polymerization of the natural copal resin samples,and the bond breaking of the conjugated double bond on the side chain of the terpenes.Thus it turns into green,yellow-green,dark-orange and black copal resins（heat-pressurized treatment）,which have the great commercial value.The microstructure,IR spectra and 13C NMR resonance spectra of the copal resin samples before and after heat-pressurized treatment are investigated in depth by using SEM,FTIR,13C NMR and so on.The results show that the heat-pressurized treatment leads to the mutual polymerization of the primary particles in copal resin samples,forming the secondary irregular micro-spherical particles with a size of 180～210 nm.The micro-spherical particles are randomly distributed with the good interface bonding.The corresponding infrared absorption spectra at 3 077（νC-H）,1 643（νC=C）,889 cm-1（νC-H）and the 13C NMR peak（chemical shift： δ=15.8×10^-6,82.0×10^-6,108.0×10^-6,215.1×10^-6） gradually disappear.The derived 13C NMR peak（chemical shift： δ=135×10^-6～137×10^-6and δ=33.9×10^-6）is of great significance in the identification.