Thermoplastic elastomers based on poly (butylene terephthalate) (PBT) and poly (ethylene glycol) (PEG) were studied by bending-creep measurements. The dependence of the creep compliance on the composition of the block copolymer was determined, and the experimental results were compared with calculat
Mechanical properties of native and crosslinked gelatins in a bending deformation
โ Scribed by A. A. Apostolov; D. Boneva; E. Vassileva; J. E. Mark; S. Fakirov
- Publisher
- John Wiley and Sons
- Year
- 2000
- Tongue
- English
- Weight
- 212 KB
- Volume
- 76
- Category
- Article
- ISSN
- 0021-8995
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โฆ Synopsis
Gelatin samples, native and chemically crosslinked with three different diisocyanates, were studied by bending-creep measurements. These samples were characterized by the number-average molecular weight of a chain segment between two points of crosslinkage M c . The chemical network was found to contribute to a marked extent to the mechanical behavior of the samples. The dependence of the creep compliance on the time for different loads was determined. The experimental results were compared with calculated ones according to a model, comprising four parameters, to obtain a better understanding of structure-property relationships for these materials. A very good agreement between the model and experimental data was found. Two of the fitting parameters, however-the relaxation time and (which is connected with the viscosity)-were found to strongly depend on the time of the experiment.
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