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| 003 | MX-MdCICY | ||
| 005 | 20250625160205.0 | ||
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| 090 | _aB-17164 | ||
| 245 | 1 | 0 | _aViscoelastic relaxations and thermal properties of bacterial poly (3-hydroxybutyrate-co-3-hydroxyvalerate)and poly (3-hydroxybutyrate-co-4-hydroxybutyrate) |
| 490 | 0 | _vInternational Journal of Biological Macromolecules, 12(2), p.112-117, 1990 | |
| 520 | 3 | _a3-Hydroxybutyrate-3-hydroxyvalerate (3HB-3HV)as well as 3-hydroxybutyrate-4-hydroxybutyrate (3HB-4HB)copolyesters have been investigated by differential scanning calorimetry, thermogravimetric analysis and dynamic mechanical spectroscopy, over a wide range of compositions (0-95 mol percent 3HV; 0-82 mol percent 4HB). Both series of isolated copolyesters are partially crystalline at all compositions. Quenched samples show a glass transition that decreases linearly with increasing co-monomer molar fraction, more markedly when the co-monomer is 4HB. Above Tg, all copolyesters, rich in 3HB units, show a cold crystallization phenomenon followed by melting, while at the other end crystallization on heating is observed only in 3HB-3HV copolymers. The viscoelastic spectrum, strongly affected by thermal history, shows two relaxation regions; the glass transition, whose location depends on copolymer type and composition, and a secondary dispersion region at low temperatures (?130?80°C). The latter results from a water-related relaxation analogous to that of P(3HB)and, in 3HB-4HB copolymers, from another overlapping absorption peak centred at ?130°C, attributed to local motion of the methylene groups in the linear 4HB units. | |
| 650 | 1 | 4 | _aPOLY(3-HYDROXYBUTYRATE-3-HYDROXYVALERATE) |
| 650 | 1 | 4 | _aPOLY(3-HYDROXYBUTYRATE-4-HYDROXYBUTYRATE) |
| 650 | 1 | 4 | _aBIOPOLYMERS |
| 650 | 1 | 4 | _aVISCOELASTICITY |
| 650 | 1 | 4 | _aTHERMAL PROPERTIES |
| 700 | 1 | 2 | _aScandola, M. |
| 700 | 1 | 2 | _aCeccorulli, G. |
| 700 | 1 | 2 | _aDoi, Y. |
| 856 | 4 | 0 |
_uhttps://drive.google.com/file/d/1R7-jScBophMcQYVtdhOAvfQW4DAhcebe/view?usp=drivesdk _zPara ver el documento ingresa a Google con tu cuenta: @cicy.edu.mx |
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