Photo-Induced Polymerization Reactions: Quantitative Information via Mass Spectrometry and Femtosecond Pump-Probe Absorption Studies

光诱导聚合反应：通过质谱和飞秒泵浦探针吸收研究获得定量信息

基本信息

批准号：
158927932
负责人：
Professor Dr. Christopher Barner-Kowollik
金额：
--
依托单位：
Institut für Physikalische Chemie (IPC)
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2009
资助国家：
德国
起止时间：
2008-12-31 至 2015-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/158927932?language=en
关键词：
Photo Induced Polymerization Reactions Quantitative

项目摘要

The current extension request builds on the work of the past 2.5 years funded by the DFG on the topic of Quantifying the Reactivity of Photolytically Generated Radicals Towards Vinylic Monomers via Electrospray Ionization Mass Spectrometry (ESI-MS), where the foundation was laid for achieving an in-depth quantitative understanding of photo-initiation processes via the provision of relative net initiation ratios associated with individual radical fragments originating from various photoinitiators. In the course of the research we found unexpectedly that femtosecond spectroscopy in combination with the pulsed laser polymerization size-exclusion chromatography ESI-MS (PLP-SEC-ESI-MS) experiments yield not only insights into the relative net efficiency of a radical fragment, but also allows to correlate the observed net efficiencies with the internal energy distribution within the excited molecule, i.e. the efficiency of the singlet to triplet intersystem crossing after laser excitation. The original grant has led to the study of 9 initiation systems leading to 4 peer-reviewed research outputs (as well as additional forthcoming manuscripts) that highlight the power of our combined experimental approach to for the first time generate quantitative knowledge about net efficiencies of photoinitiators with their internal energy dissipation channels. Within the requested extension project, we now wish to exploit our combined experimental set-up in a collaborative project between the KIT Polymer and Physical Chemistry institutes. The key aim is the quantitative determination of the relative net initiation efficiency via the now established PLP-SEC-ESI-MS technique for a wide range of radical fragments coupled with the quantitative understanding of the intersystem crossing behavior of the constituting initiator molecules, to arrive at a map of origin dependent radical fragment initiation efficiencies. We believe that a unique opportunity exists to for the first time provide a full and comprehensive understanding of final polymer end group distribution of photolytically generated radical fragments with the structure dependent internal energy conversion within the photoinitiators.

当前的扩展请求建立在DFG资助的过去2。5年的工作基础上，该主题是通过电源喷雾电离质谱法（ESI-MS）量化光解产生的对Vinyllic单体的反应性的，该基础是为实现基础而实现的基础通过提供与源自各种光初始化者的个体激进片段相关的相对净起始比，对光化过程的深入定量理解。在研究过程中，我们出乎意料地发现，飞秒光谱法与脉冲激光聚合尺寸 - 分类色谱ESI-MS（PLP-SEC-ESI-MS）实验相结合，不仅可以洞悉洞察力，不仅可以洞悉自由基效率的相对净效率，即但还允许将观察到的净效率与激发分子内的内部能量分布相关联，即激光激发后单线对三重态交叉的效率。最初的赠款导致对9个启动系统的研究，导致了4个经过同行评审的研究输出（以及其他即将到来的手稿），从而突出了我们合并实验方法的力量，以首次产生有关光学家净效率的定量知识及其内部能量耗散通道。在所需的扩展项目中，我们现在希望在套件聚合物和物理化学机构之间的协作项目中利用我们合并的实验设置。关键目的是通过现已建立的PLP-SEC-ESI-MS技术定量确定相对净起始效率，用于广泛的激进片段，以及对构造引发剂分子的交叉行为的定量理解，以达到到达在原点依赖性的自由基碎片起始效率上。我们认为，首次存在独特的机会，对光解产生的激进片段的最终聚合物端群分布提供了完全，全面的理解，其结构依赖于光构体内的结构。