Abstract

It is well documented that in semi-crystalline polymers crystallization is strongly influenced by thermal and flow conditions that the polymer experiences during its shaping process. It is also becoming evident that the processing conditions are strongly influenced by the entangled state that are established in the non-crystalline region during polymerization of a semi-crystalline polymer. The strong influence of the entangled state in the processing is realized when an intractable polymer can be processed even below its melting point. Two such examples that are documented in the literature are of linear polyethylene and isotactic polypropylene, both having molar mass exceeding a million g/mol. 

In this paper we will demonstrate that the controlled polymer synthesis can result into the formation of single-crystals that are identified by scanning / transmission electron microscopy, imaging and diffraction techniques. Within these single crystals, solid state NMR identifies constrained chain segments residing in the non-crystalline region. Such single crystals can be deformed uniaxially and biaxially in solid state and are linked with the polymerization conditions. The knowhow thus developed is extended beyond polyethylene and isotactic polypropylene that the paper will address. 

References:

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   Acknowledgement: The author extends thanks to his group members at KAUST whose contribution lead to the present abstract and forum for the presentation. To name, Dr Dario Romano, Dr Sumesh Raman, Dr Yogesh Patil, Dr Jiayi Zhao, Dr Joris van der Eem, Dr Feijie Li, Mr Ravindra Gote, Mr Fuhai Zhou, Mr Abulaziz Alsubhi. We extend thanks to Dr Virendra Gupta of Reliance Industries Limited for a part of work to be reported on isotactic polypropylene. Financial support from KAUST and the expertise available at the KAUST core labs is gratefully acknowledged.

Bio

Sanjay Rastogi is a full professor in Physical Science and Engineering Division of KAUST. He joined KAUST in October 2020. His expertise is in combining molecular architecture perceived during polymer synthesis with ease in polymer processing, polymer rheology and development of composites. He has set an active group in polymer science and engineering at KAUST that aligns with the RDIA vision with the Kingdom.

After spending nearly four years at Bristol University (UK) in the group of the late Professor Andrew Keller, Sanjay spent nearly 20 years as Assistant and Associate Professor at the Eindhoven University of Technology (NL) and was instrumental in setting up the core program of the Dutch Polymer Institute. Sanjay spent nearly 7 years in industry (Teijin Aramid, The Netherlands) to translate the innovation developed in the university to industry and is an inventor of the new environmental friendly process of the strongest man-made fibers and films that can be used for several applications including pipe and films for Lithium-ion batteries. Before moving to KAUST he was a full professor at Loughborough University (UK) and Maastricht University (NL), where he established academic groups integrating with industries in the region.

Sanjay spent nearly 7 years in industry (Teijin Aramid, The Netherlands) to translate the innovation developed in the university to industry and is an inventor of the new environmental friendly process of the strongest man-made fibers and films that can be used for several applications including pipe and films for Lithium-ion batteries. Before moving to KAUST he was a full professor at Loughborough University (UK) and Maastricht University (NL), where he established academic groups integrating with industries in the region.

Sanjay has been a recipient of Max Planck Society fellowship, and an Outstanding Scientist at the Council for Science and Industrial Research, National Chemical Lab in India. During his stay with the industry, he was recognized as a Senior Technical Expert of Teijin Group. He holds executive MBA degree from Rotterdam School of Management, which was financially supported by Teijin.  

Sanjay has authored more than 180 scientific peer reviewed publications and 30 patent applications. So far, 29 PhD students have successfully graduated under his supervision in the Netherlands, UK, and KAUST.