TY - JOUR
T1 - Impact of fermentation residues on the thermal, structural, and rheological properties of polyhydroxy(butyrate-co-valerate) produced from cheese whey and olive oil mill wastewater
AU - Hilliou, Loic
AU - Machado, Diogo
AU - Oliveira, Catarina S. S.
AU - Gouveia, Ana R.
AU - Reis, Maria A.M.
AU - Campanari, Sabrina
AU - Villano, Marianna
AU - Majone, Mauro
N1 - Publisher Copyright:
© 2015 Wiley Periodicals, Inc.
Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 2016/1/10
Y1 - 2016/1/10
N2 - The effects of recovered residues on the characteristics of polyhydroxy(butyrate-co-valerate) (PHBV) produced from mixed microbial cultures (MMCs) fed with cheese whey, olive oil mill wastewater, or a synthetic mixture of acetic and propionic acid were investigated. The different types of MMC PHBVs were extracted and purified with different downstream routes; this enabled the recovery of polymers with different hydroxyvalerate contents and different residue types and levels, ranging from 0 to 11%. The results indicate overall that the recovery of residues together with the biopolymer brought benefits to the melt processability of these MMC PHBVs. Impurities triggered thermal degradation at smaller temperatures, promoted melting at lower temperatures, acted as thermal stabilizers, improved the melt viscosity, and enhanced the shear thinning. The degree of crystallinity of the aged samples was not affected by the impurities, but the crystallites size increased. MMC PHBVs recovered with residues containing more proteins showed better thermal stability, whereas MMC PHBVs containing more inorganic residues showed better melt viscoelastic properties. The results of this study show that impurities recovered together with the MMC PHBVs introduced changes to their thermal, semicrystalline, and rheological properties; these changes, in some cases, were detrimental, but they were also potentially advantageous to the processing and conversion of these materials into products such as packages.
AB - The effects of recovered residues on the characteristics of polyhydroxy(butyrate-co-valerate) (PHBV) produced from mixed microbial cultures (MMCs) fed with cheese whey, olive oil mill wastewater, or a synthetic mixture of acetic and propionic acid were investigated. The different types of MMC PHBVs were extracted and purified with different downstream routes; this enabled the recovery of polymers with different hydroxyvalerate contents and different residue types and levels, ranging from 0 to 11%. The results indicate overall that the recovery of residues together with the biopolymer brought benefits to the melt processability of these MMC PHBVs. Impurities triggered thermal degradation at smaller temperatures, promoted melting at lower temperatures, acted as thermal stabilizers, improved the melt viscosity, and enhanced the shear thinning. The degree of crystallinity of the aged samples was not affected by the impurities, but the crystallites size increased. MMC PHBVs recovered with residues containing more proteins showed better thermal stability, whereas MMC PHBVs containing more inorganic residues showed better melt viscoelastic properties. The results of this study show that impurities recovered together with the MMC PHBVs introduced changes to their thermal, semicrystalline, and rheological properties; these changes, in some cases, were detrimental, but they were also potentially advantageous to the processing and conversion of these materials into products such as packages.
KW - Biodegradable
KW - Biopolymers and renewable polymers
KW - Rheology
KW - Thermal properties
UR - http://www.scopus.com/inward/record.url?scp=84944155546&partnerID=8YFLogxK
U2 - 10.1002/app.42818
DO - 10.1002/app.42818
M3 - Article
AN - SCOPUS:84944155546
SN - 0021-8995
VL - 133
JO - Journal of Applied Polymer Science
JF - Journal of Applied Polymer Science
IS - 2
M1 - 42818
ER -