【摘要】 合成了14种不同组成的聚酯样品以考察聚酯端羟基α-H的1H谱谱峰特点。利用聚酯端羟基α-H的1H谱谱峰与聚酯其它峰互不干扰的特点,采用优化的1H谱脉冲序列和检测参数,以苯乙烯为内标,建立了一种用核磁共振1H谱检测聚酯端羟基α-H在聚酯中的含量,再根据端羟基α-H与羟基的比例关系求聚酯羟值的方法。结果显示,其测量的相对偏差小于1%,测量精密度为±0.2。本方法简单、快速、准确度高。更多还原

【Abstract】 Fourteen kinds of polyesters were synthesized, which is to study the characteristics of terminal hydroxyl α-H of polyester in ~1H nuclear magnetic resonance (NMR) spectra. Utilizing the results that the peak of terminal hydroxyl α-H of polyester does not interfere by other peaks of polyester, a new simple and sensitive method to determine the hydroxyl value of polyester by ~1H NMR was established. In this method, a modified ~1H NMR pulse sequence and improved parameters were adopted, and styrene was added as the internal standard . The investigated results show that the relative error of theoretica values and measured valuew in this method is lower than 1% and the precision is ±0.2. This method is characterized not only by simplicity and rapidity but also by high precision.更多还原