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Anisotropic Thermal Expansion of Transparent Cellulose Nanopapers.

ABSTRACT: We report the anisotropic thermal expansion of a transparent nanopaper structure comprising cellulose nanofibers (CNFs). The coefficient of thermal expansion (CTE) of the nanopaper in the out-of-plane direction was 44.6 ppm/°C in the temperature range of 25-100°C, which is approximately five times larger than its CTE in the in-plane direction in the same temperature range (8.3 ppm/°C). Such a strong anisotropy in thermal expansion is mainly attributable to the anisotropic CTE values of single CNFs in the fiber axis and cross-sectional directions. We observed anisotropic thermal expansion even in a bioplastic composite containing only 2.5% w/w CNFs.

SUBMITTER: Hirano T

PROVIDER: S-EPMC7019374 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Anisotropic Thermal Expansion of Transparent Cellulose Nanopapers.

Hirano Takayuki T Mitsuzawa Kana K Ishioka Shun S Daicho Kazuho K Soeta Hiroto H Zhao Mengchen M Takeda Masaaki M Takai Yoshihiro Y Fujisawa Shuji S Saito Tsuguyuki T

Frontiers in chemistry 20200207

We report the anisotropic thermal expansion of a transparent nanopaper structure comprising cellulose nanofibers (CNFs). The coefficient of thermal expansion (CTE) of the nanopaper in the out-of-plane direction was 44.6 ppm/°C in the temperature range of 25-100°C, which is approximately five times larger than its CTE in the in-plane direction in the same temperature range (8.3 ppm/°C). Such a strong anisotropy in thermal expansion is mainly attributable to the anisotropic CTE values of single CN ...[more]

PMID: 32117891

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