Acyclic Diene Metathesis Polymerization

9520803瓦格纳通过确定在缩合反应中可以容忍的官能团，在最近的资助期内证明了非环二烯歧化(ADMET)聚合的可行性。这种新的化学已经导致了通过解聚反应合成的遥控烃类聚合物，以及许多先进的聚合物系统。这笔赠款涉及四个大致相关的研究领域，这些领域扩展了迄今为止在ADMET聚合方面所做的工作。我们将探索共轭双烯的化学。碳氢化合物共轭双烯将首先被检测，然后展开为芳香共轭双烯。与末端脂肪族双烯相关的机理之谜将被阐明。此外，ADMET化学的催化剂基础将扩大到包括相当便宜的系统，这些反应的速度(动力学)将被详细地阐明，以便很好地理解这些结果的实际应用。为了提高废塑料体系的可回收性，将制备热可逆网络聚合物，最后将制备手性聚合物以扩大这一新化学的用途。从过去三年美国国家科学基金会支持的美国工业的反应来看，人们对ADMET化学的商业用途的兴趣很高。特别重要的是在特种聚合物的合成、具有高商业价值的目标分子的制备(通过解聚)以及ADMET化学在众所周知的商业聚合物(如聚丁二烯)的再利用中的应用。这种更新建立在所有这些机会的基础上。***

9520803 Wagener The viability of acyclic diene metathesis (ADMET) polymerization has been demonstrated during the most recent funding period by identifying the functionalities which can be tolerated during this condensation reaction. This new chemistry has led to telechelic hydrocarbon polymers synthesized by depolymerization reactions, as well as to many advanced polymer systems. This grant addresses four generally related research areas which expand upon what has been done thus far with ADMET polymerization. The chemistry of conjugated dienes will be explored. Hydrocarbon conjugated dienes will be examined fipst followed by expansion to aromatic conjugated dienes. The mechanistic enigma associated with terminal aliphatic dienes will be elucidated. Further, the catalyst base for ADMET chemistry will be expanded to include considerably less expensive systems, and speed of these reactions (the kinetics) will be elucidated in such detail that the practical application of these results will be well understood. Thermoreversible network polymers will be made with the goal of improving the recyclability of waste plastics systems, and finally, chiral polymers will be prepared to broaden the utility of this new chemistry. %%% Interest in the commercial utility of ADMET chemistry is high, as judged by the response from American industry during the past three years of NSF support. Particularly significant are applications to the synthesis of specialty polymers, the preparation (via depolymerization) of targeted molecules of high commercial value, and the utility of ADMET chemistry in the reuse of well known commercial polymers, such as polybutadiene. This renewal builds upon all of these opportunities. ***