【摘要】 基于原子力显微镜技术的单分子力谱方法及圆二色谱法,从单分子水平定量研究了侧链带有酰胺键的聚苯乙炔衍生物所形成的螺旋结构稳定性及影响因素.单分子力谱实验结果表明,向体系中掺杂碘单质后,高分子主链螺旋结构稳定性下降,力谱拉伸曲线平台力值降低;升高溶液pH值后,高分子主链螺旋结构完整性下降,力谱拉伸曲线平台长度缩短.更多还原

【Abstract】 We quantitatively investigated the effect of iodine and pH on the stability of the helical structure formed by polyphenylacetylene derivatives using atomic force microscopy(AFM) based single-molecule force spectroscopy(SMFS) and circular dichroism(CD). The AFM measurement results showed that the addition of iodine into the system caused the decrease of the plateau heights in the stretching curves recorded during the SMFS experiments. In addition,the pH value increase can weaken the intra-polymer hydrogen bond and interrupt the integrity of the helical structure. However,the CD result did not show any detectable changes upon the addition of iodine and the change of pH value,which indicate that SMFS is a very sensitive and powerful method for subtle structure study.更多还原