TY - JOUR

T1 - Introducing Students to Energy-Efficient Mechanochemistry of Biopolymers

AU - Bychkov, Aleksey

AU - Matveeva, Anna

N1 - Funding Information: This work was supported by the Russian Science Foundation (Project No. 19-73-10074 “Energy Aspects of Mechanochemical Processing of Polymers of Plant Raw Materials”). The studies involving cellulose particle size measurements were previously supported by a grant from the Russian Science Foundation (Project No. 21-13-00046). Publisher Copyright: © 2022 American Chemical Society and Division of Chemical Education, Inc.

PY - 2022/7/12

Y1 - 2022/7/12

N2 - A comprehensive laboratory work that allows students to gain hands-on skills in energy-efficient mechanochemistry is described. Standard university curricula are paying very little attention to mechanochemistry, although skills in this discipline are highly demanded among chemistry graduates. In this study, a comprehensive description of mechanical destruction of α-cellulose was chosen as a model task for students to perform. The structure of cellulose is best suitable for demonstrating the effects occurring upon mechanical treatment. While being sufficiently complex (as it is characterized by high molecular weight and the presence of crystalline and amorphous regions), cellulose is simultaneously rather simple (as it consists of glucose units only and contains no branching) and allows one to consider rupturing of a macromolecule chain as the only possible mechanochemical reaction. This study employs the view commonly held in mechanochemistry that the field of mechanical forces undergoes relaxation through the following pathways: heating of the system, grinding of material, amorphization of the crystalline structure, and occurrence of mechanochemical reactions. This multilevel investigation of the process according to the "bottom up"approach has allowed the students to identify the relaxation pathways through which energy is expended during treatment of amorphous/crystalline biopolymers. It is safe to say that this approach allows the new generation of chemists not only to routinely assess and enhance the energy efficiency of the existing technologies but also to develop novel technologies employing hardly accessible and nonreactive substances.

AB - A comprehensive laboratory work that allows students to gain hands-on skills in energy-efficient mechanochemistry is described. Standard university curricula are paying very little attention to mechanochemistry, although skills in this discipline are highly demanded among chemistry graduates. In this study, a comprehensive description of mechanical destruction of α-cellulose was chosen as a model task for students to perform. The structure of cellulose is best suitable for demonstrating the effects occurring upon mechanical treatment. While being sufficiently complex (as it is characterized by high molecular weight and the presence of crystalline and amorphous regions), cellulose is simultaneously rather simple (as it consists of glucose units only and contains no branching) and allows one to consider rupturing of a macromolecule chain as the only possible mechanochemical reaction. This study employs the view commonly held in mechanochemistry that the field of mechanical forces undergoes relaxation through the following pathways: heating of the system, grinding of material, amorphization of the crystalline structure, and occurrence of mechanochemical reactions. This multilevel investigation of the process according to the "bottom up"approach has allowed the students to identify the relaxation pathways through which energy is expended during treatment of amorphous/crystalline biopolymers. It is safe to say that this approach allows the new generation of chemists not only to routinely assess and enhance the energy efficiency of the existing technologies but also to develop novel technologies employing hardly accessible and nonreactive substances.

KW - Cellulose

KW - Energy Efficiency

KW - Graduate Education

KW - Hands-On Learning

KW - Mechanochemistry

KW - Polymer Chemistry

KW - Research

KW - Second-Year Undergraduate

KW - X-ray Crystallography

UR - http://www.scopus.com/inward/record.url?scp=85134495002&partnerID=8YFLogxK

U2 - 10.1021/acs.jchemed.1c01164

DO - 10.1021/acs.jchemed.1c01164

M3 - Article

AN - SCOPUS:85134495002

VL - 99

SP - 2630

EP - 2635

JO - Journal of Chemical Education

JF - Journal of Chemical Education

SN - 0021-9584

IS - 7

ER -