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Mechanical response of reconstituted, freeze-dried collagen under compression loads Khosla, Amardeep Singh
Abstract
The mechanical response under uniaxial compression of collagen discs, made from freeze-dried collagen reconstituted at acid pH, was investigated at 22, 29.5, and 35°C (±0.3 C°). The pH during compression was maintained near the physiological level of 7.40-5. Connective tissues are known to be non-linear viscoelastic materials. It was felt, however, that the linearized, fluid transport-based model developed by Bert (1970) would adequately describe the behaviour of collagen "for small changes in hydration. [The model is linearized through the assumption that the diffusion coefficient, D(H), is a weak function of hydration, and is therefore constant for small changes in hydration]. The average diffusion coefficient, D(H), and the flow condictivity,k/n, were found to be stronger functions of hydration than expected in the hydration range investigated [1.9 to 5.5 g H₂O/g collagen], and this may have increased scatter in the results. Average values of D(H) and k/n at hydration 3.0 g H₂O/g collagen [i.e. skin hydration] were ~ 3.5x10⁻⁷cm²/s and ~ 6.0x10⁻¹¹cm⁴/dyne-s respectively. The compressive response of collagen was only weakly influenced by temperature, and possible thermal degradation of the molecules was indicated at 35°C. Some creep was also noted at times >5 t[sub ½], but no attempt was made to quantify it.
Item Metadata
Title |
Mechanical response of reconstituted, freeze-dried collagen under compression loads
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Creator | |
Publisher |
University of British Columbia
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Date Issued |
1981
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Description |
The mechanical response under uniaxial compression of collagen discs, made from freeze-dried collagen reconstituted at acid pH, was investigated
at 22, 29.5, and 35°C (±0.3 C°). The pH during compression was maintained near the physiological level of 7.40-5.
Connective tissues are known to be non-linear viscoelastic materials. It was felt, however, that the linearized, fluid transport-based model developed by Bert (1970) would adequately describe the behaviour of collagen "for small changes in hydration. [The model is linearized through the assumption that the diffusion coefficient, D(H), is a weak function of hydration, and is therefore constant for small changes in hydration].
The average diffusion coefficient, D(H), and the flow condictivity,k/n, were found to be stronger functions of hydration than expected in the hydration range investigated [1.9 to 5.5 g H₂O/g collagen], and this may have increased scatter in the results. Average values of D(H) and k/n at hydration 3.0 g H₂O/g collagen [i.e. skin hydration] were ~ 3.5x10⁻⁷cm²/s and ~ 6.0x10⁻¹¹cm⁴/dyne-s respectively.
The compressive response of collagen was only weakly influenced by temperature, and possible thermal degradation of the molecules was indicated at 35°C. Some creep was also noted at times >5 t[sub ½], but no attempt was made to quantify it.
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Genre | |
Type | |
Language |
eng
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Date Available |
2010-03-26
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Provider |
Vancouver : University of British Columbia Library
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Rights |
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
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DOI |
10.14288/1.0058922
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URI | |
Degree | |
Program | |
Affiliation | |
Degree Grantor |
University of British Columbia
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Campus | |
Scholarly Level |
Graduate
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Aggregated Source Repository |
DSpace
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Rights
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.