Development of Next Generation Living Coordinative Chain Transfer Polymerization and New Polyolefin Materials Obtained Therefrom

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Wallace, Mark Alexander
Sita, Lawrence R
The living polymerization of ethene, propene, higher carbon-number linear and branched chain α-olefins, and α,ω-nonconjugated dienes has provided the basis for the development of modern technological advances and achievements. The use of polyolefin materials is ubiquitous through the many plastic products produced on an over 300-million-metric-ton global scale annually. The sheer range and scope of these products is further underscored by the fact that such diversity is achieved from a very limited number of industrially relevant olefin monomer feedstocks. As such, continued advancement of polyolefin materials has been achieved through the design and validation of new polymerization methods and transition-metal catalysts that allow for the controlled production of polyolefins with tailored architectural features and physical properties. Furthermore, these methods and materials must generate the desired products in a fashion that is both cost effective and amenable to large scale production.Towards this goal, the work herein presents the design, validation, and implementation of ‘next generation’ living coordinative chain transfer polymerization (LCCTP) through five new polymerization methods for the synthesis of polyolefin materials with new functionalities, stereochemical configurations, optical activities, and with tailored molecular weight distribution profile and dispersity. These new methods include the design of a novel homochiral group 4 cyclopentadienyl, caproamidinate (CPAM) hafnium pre-initiator that exhibits unprecedented configurational stability. Most importantly, these new LCCTP methods allow for the generation of different classes of polyolefin materials in a controlled and scalable manner. Discussions concerning the design and application of these new methods, the materials they produce, and the future of these new advances will be presented.