Effect of degree of substitution on the microphase separation and mechanical properties of cellooligosaccharide acetate-based elastomers

Satoshi Katsuhara; Naoki Sunagawa; Kiyohiko Igarashi; Yutaka Takeuchi; Kenji Takahashi; Takuya Yamamoto; Feng Li; Kenji Tajima; Takuya Isono; Toshifumi Satoh

doi:10.1016/j.carbpol.2023.120976

Effect of degree of substitution on the microphase separation and mechanical properties of cellooligosaccharide acetate-based elastomers

Carbohydr Polym. 2023 Sep 15:316:120976. doi: 10.1016/j.carbpol.2023.120976. Epub 2023 May 5.

Authors

Affiliations

¹ Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo 060-8628, Japan.
² Department of Biomaterial Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan.
³ Department of Biomaterial Sciences, Graduate School of Agriculture and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan; VTT Technical Research Centre of Finland Ltd., VTT FI-02044, Finland.
⁴ Noto Center for Fisheries Science and Technology, Faculty of Biological Science and Technology, Kanazawa University, Noto-cho, Ishikawa 927-0552, Japan.
⁵ Faculty of Biological Science and Technology, Institute of Science and Engineering, Kanazawa University, Kanazawa 920-1192, Japan.
⁶ Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
⁷ Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan. Electronic address: ktajima@eng.hokudai.ac.jp.
⁸ Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan. Electronic address: isono.t@eng.hokudai.ac.jp.
⁹ Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan. Electronic address: satoh@eng.hokudai.ac.jp.

PMID: 37321706
DOI: 10.1016/j.carbpol.2023.120976

Abstract

Thermoplastic elastomers (TPEs) have long been used in a wide range of industries. However, most existing TPEs are petroleum-derived polymers. To realize environmentally benign alternatives to conventional TPEs, cellulose acetate is a promising TPE hard segment because of its sufficient mechanical properties, availability from renewable sources, and biodegradability in natural environments. Because the degree of substitution (DS) of cellulose acetate governs a range of physical properties, it is a useful parameter for designing novel cellulose acetate-based TPEs. In this study, we synthesized cellulose acetate-based ABA-type triblock copolymers (AcCel_x-b-PDL-b-AcCel_x) containing a celloologosaccharide acetate hard A segment (AcCel_x, where x is the DS; x = 3.0, 2.6, and 2.3) and a poly(δ-decanolactone) (PDL) soft B segment. Small-angle X-ray scattering showed that decreasing the DS of AcCel_x-b-PDL-b-AcCel_x resulted in the formation of a more ordered microphase-separated structure. Owing to the microphase separation of the hard cellulosic and soft PDL segments, all the AcCel_x-b-PDL-b-AcCel_x samples exhibited elastomer-like properties. Moreover, the decrease in DS improved toughness and suppressed stress relaxation. Furthermore, preliminary biodegradation tests in an aqueous environment revealed that the decrease in DS endowed AcCel_x-b-PDL-b-AcCel_x with greater biodegradability potential. This work demonstrates the usefulness of cellulose acetate-based TPEs as next-generation sustainable materials.

Keywords: Biodegradability; Cellulose acetate; Mechanical properties; Microphase separation; Self-assembly; Thermoplastic elastomer.

MeSH terms

Elastomers* / chemistry
Temperature

Substances

Elastomers