对弱信号具有高响应灵敏度的温敏超支化聚酰胺-胺的合成、表征及应用研究

To date, the application of thermoresponsive polymer in fields of sensor and separation-recycling loses the practical value, when the sensitivity of the temperature-responsive macromolecule is poor even unresponsive because of the weak external signals. However, the sensitivity will be amplified or improved by introduction of characteristic groups such as recognized molecules/ions and photosensitive perssad. A novel intelligent macromolecule which could respond to weak signals will be constructed, and it will achieve more favorable applications in various high-tech fields including drug controlled-release systems, sensors and separation,etc. Therefore, in this project, we shall design and synthesize a series of thermoresponsive hyperbranched polymers which could recognize molecules or ions by adding single/coupling/series-wound cyclodextrin,crown ether or calixarene.The photosensitive group will also be further grafted selectively as needed in order to increae sensitivity.These novel macromolecules responding to weak signal will be characterized well.The influences of hyperbranched polyamidoamine molecular weight, pH, ionic species, ionic concentration and graft ratio on the temperature sensibility will be studied. Meanwhile, the effects of separation and recovery will be investigated especially when the guest concentration (mainly metal ions) is low; and the sensitivity of these sensors will also be estimated so as to improve the performance of thermoresponsive materials and broaden its application fields.

目前，温敏聚合物在传感器和分离回收等方面的应用中，当外界刺激信号较弱时其响应灵敏度较差、甚至无响应，从而使其失去应用价值。通过引入分子或离子识别、光敏感等特性基团可以放大或提高其响应灵敏度，构造出新型的响应弱信号的智能高分子，更好地实现其在药物控释、传感器和分离体系等高新技术领域的应用。因此，本项目将具有"主-客体"识别性能的单个、偶联或串联的环糊精、冠醚、杯芳烃首次引入到温敏超支化聚酰胺-胺上，制备出一系列分子、离子识别型温敏高分子，进一步根据需要选择性接枝光敏感分子，加强其对外界信号的响应灵敏度。对这些新型的弱信号响应高分子进行充分表征，研究超支化聚酰胺-胺分子量、pH、离子种类和浓度、各响应基团接枝率对温敏性能的影响，同时，考察其在客体浓度（主要是金属离子等）较低情况下的分离回收效果以及作为传感器进行检测时的灵敏度，提高温敏材料的应用性能，拓宽其应用领域。

超支化温敏聚合物因其对外界温度、pH、盐度等具有刺激响应特性而在基础和应用研究方面受到广泛关注。在国家自然科学基金的资助下，我们制备了不同壳层结构的超支化温敏聚合物或其纳米复合物，实现了在弱信号条件下对重金属离子的检测、富集和分离，在环境修复和污水分析等方面具有较好的应用前景。基于超支化温敏聚合物稳定的金纳米粒子形成核壳或合金结构伴随引起颜色变化的原理发展了一种新型比色传感检测方法，该方法相比因金纳米粒子聚集而引起红到蓝或红到紫颜色变化的传统比色传感器具有更高的灵敏度和选择性。采用核磁、扫描、透射电镜、X射线衍射等技术分析和表征了材料的结构和检测机理。系统探索了聚合物结构、纳米粒子尺寸、组成等因素对银离子检测、汞离子检测和分离、染料负载、铅离子吸附性能的影响，对超支化聚合物的结构与性能间的构效关系有了深入了解。部分工作已正式发表在Chemical Engineering Journal（1篇）, Sensors and Actuators B: Chemical（1篇）, Analyst（1篇）, Analytical Methods（1篇）, RSC Advances（2篇）, Catalysts（1篇）等期刊上。