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Housing tubes from the marine worm Chaetopterus sp.: biomaterials with exceptionally broad thermomechanical properties.

ABSTRACT: The housing tube material of the marine worm Chaetopterus sp. exhibits thermal stability up to 250°C, similar to other biological materials such as mulberry silkworm cocoons. Interestingly, however, dynamic mechanical thermal analysis conducted in both air and water elucidated the lack of a glass transition in the organic tube wall material. In fact, the viscoelastic properties of the anhydrous and undried tube were remarkably stable (i.e. constant and reversible) between -75°C and 200°C in air, and 5°C and 75°C in water, respectively. Moreover, it was found that hydration and associated-water plasticization were key to the rubber-like flexible properties of the tube; dehydration transformed the material behaviour to glass-like. The tube is made of bionanocomposite fibrils in highly oriented arrangement, which we argue favours the biomaterial to be highly crystalline or cross-linked, with extensive hydrogen and/or covalent bonds. Mechanical property characterization in the longitudinal and transverse directions ascertained that the tubes were not quasi-isotropic structures. In general, the higher stiffness and strength in the transverse direction implied that there were more nanofibrils orientated at ± 45° and ± 65° than at 0° to the tube axis. The order of the mechanical properties of the soft-tough tubes was similar to synthetic rubber-like elastomers and even some viscid silks. The complex structure-property relations observed indicated that the worm has evolved to produce a tubular housing structure which can (i) function stably over a broad range of temperatures, (ii) endure mechanical stresses from specific planes/axes, and (iii) facilitate rapid growth or repair.

SUBMITTER: Shah DU

PROVIDER: S-EPMC4233702 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature

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Housing tubes from the marine worm Chaetopterus sp.: biomaterials with exceptionally broad thermomechanical properties.

Shah Darshil U DU Vollrath Fritz F Porter David D Stires John J Deheyn Dimitri D DD

Journal of the Royal Society, Interface 20140901 98

The housing tube material of the marine worm Chaetopterus sp. exhibits thermal stability up to 250°C, similar to other biological materials such as mulberry silkworm cocoons. Interestingly, however, dynamic mechanical thermal analysis conducted in both air and water elucidated the lack of a glass transition in the organic tube wall material. In fact, the viscoelastic properties of the anhydrous and undried tube were remarkably stable (i.e. constant and reversible) between -75°C and 200°C in air, ...[more]

PMID: 25008085

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Dataset Information

Housing tubes from the marine worm Chaetopterus sp.: biomaterials with exceptionally broad thermomechanical properties.

Publications

Housing tubes from the marine worm Chaetopterus sp.: biomaterials with exceptionally broad thermomechanical properties.

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