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The Chemical Educator

ISSN: 1430-4171 (electronic version)

Table of Contents

Abstract Volume 22 (2017) pp 191-194

Illustrating Structure–Properties Relationships with Interlocking Building Block Models: Amylopectin, Amylose, and Cellulose

Ryo Horikoshi

Department of Environmental Science and Technology, Faculty of Design Technology, Osaka Sangyo University, Nakagaito, Daito, Osaka 574-8530, Japan, ryo.horikoshi@est.osaka-sandai.ac.jp
Received June 2, 2017. Accepted October 23, 2017.

Published: 6 November 2017

Abstract. In this paper, interlocking building block models are used to illustrate the structure–properties relationships of amylopectin, amylose, and cellulose. The characteristic primary structures of amylopectin, amylose, and cellulose are a highly blanched helical chain, a linear helical chain, and a linear zigzag chain, respectively. The differences in structures lead to their distinctive properties that people encounter in their daily lives. For example, the difference in stickiness between sticky rice and fluffy rice is attributable to the ratio of amylopectin and amylose in their starch. The hardness of wood is ascribable to the rigid structure of cellulose. The key issues related to structure can be distilled into interlocking building block models. With the use of these models, instructors can explain the characteristic properties related to the chain structures of amylopectin, amylose, and cellulose, including stickiness, molecular inclusion and strength.

Key Words: Laboratories and Demonstrations; organic chemistry; polymer chemistry; demonstrations; molecular modeling; molecular properties/structure

(*) Corresponding author. (E-mail: ryo.horikoshi@est.osaka-sandai.ac.jp)

Article in PDF format (268 KB) HTML format

Supporting Materials:

Constructions of the interlocking building block models, notes for instructors, and a PowerPoint slide show are available as a PDF file. (1160 KB)



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