File Download

There are no files associated with this item.

  Links for fulltext
     (May Require Subscription)
Supplementary

Article: Degradation and mineralization of cellulose acetate in simulated thermophilic compost environments

TitleDegradation and mineralization of cellulose acetate in simulated thermophilic compost environments
Authors
KeywordsBiodegradation Testing
Cellulose Acetate
Degree Of Substitution
Molecular Weight
Municipal Solid Waste
Polymer Degradation
Polymer Mineralization
Respirometry
Surface Colonization
Issue Date1993
Citation
Journal Of Environmental Polymer Degradation, 1993, v. 1 n. 4, p. 281-291 How to Cite?
AbstractResidual cellulose acetate (CA) films with initial degree of substitution (DS) values of 1.7 and 2.5 (CA DS-1.7 and DS-2.5) were recovered from a simulated thermophilic compost exposure and characterized by gel permeation chromatography (GPC), proton nuclear magnetic resonance (1H NMR), and scanning electron microscopy (SEM) to determine changes in polymer molecular weight and DS and to study microbial colonization and surface morphology, respectively. During the aerobic degradation of CA DS-1.7 and CA DS-2.5 films exposed for 7 and 18 days, respectively, the number-average molecular weight (Mn) of residual polymer decreased by 30.4% on day 5 and 20.3% on day 16, respectively. Furthermore, a decrease in the degree of substitution from 1.69 to 1.27 (4-day exposure) and from 2.51 to 2.18 (12-day exposure) was observed for the respective CA samples. In contrast, CA films (DS-1.7 and DS-2.5) which were exposed to abiotic control vessels for identical time periods showed no significant changes in Mn and DS. SEM photographs of CA (DS-1.7 and DS-2.5) film surfaces after compost exposures revealed severe erosion and corresponding microbial colonization. Similar exposure times for CA films in abiotic control vessels resulted in only minor changes in surface characteristics by SEM observations. The conversion of CA DS-1.7 and DS-2.5 to CO2 was monitored by respirometry. In these studies, powdered CA was placed in a predigested compost matrix which was maintained at 53°C and 60% moisture content throughout the incubation period. A lag phase of 10- and 25-day duration for CA DS-1.7 and DS-2.5, respectively, was observed, after which the rate of degradation increased rapidly. Mineralization of exposed CA DS-1.7 and DS-2.5 powders reported as the percentage theoretical CO2 recovered reached 72.4 and 77.6% in 24 and 60 days, respectively. The results of this study demonstrated that microbial degradation of CA films exposed to aerobic thermophilic laboratory-scale compost reactors not only results in film weight loss but also causes severe film pitting and a corresponding decrease in chain Mn and degree of substitution for the residual material. Furthermore, conversions to greater than 70% of the theoretical recovered CO2 for CA (DS 1.7 and 2.5) substrates indicate high degrees of CA mineralization. © 1993 Plenum Publishing Corporation.
Persistent Identifierhttp://hdl.handle.net/10722/178555
ISSN

 

DC FieldValueLanguage
dc.contributor.authorGu, JDen_US
dc.contributor.authorEberiel, Den_US
dc.contributor.authorMccarthy, SPen_US
dc.contributor.authorGross, RAen_US
dc.date.accessioned2012-12-19T09:48:21Z-
dc.date.available2012-12-19T09:48:21Z-
dc.date.issued1993en_US
dc.identifier.citationJournal Of Environmental Polymer Degradation, 1993, v. 1 n. 4, p. 281-291en_US
dc.identifier.issn1064-7564en_US
dc.identifier.urihttp://hdl.handle.net/10722/178555-
dc.description.abstractResidual cellulose acetate (CA) films with initial degree of substitution (DS) values of 1.7 and 2.5 (CA DS-1.7 and DS-2.5) were recovered from a simulated thermophilic compost exposure and characterized by gel permeation chromatography (GPC), proton nuclear magnetic resonance (1H NMR), and scanning electron microscopy (SEM) to determine changes in polymer molecular weight and DS and to study microbial colonization and surface morphology, respectively. During the aerobic degradation of CA DS-1.7 and CA DS-2.5 films exposed for 7 and 18 days, respectively, the number-average molecular weight (Mn) of residual polymer decreased by 30.4% on day 5 and 20.3% on day 16, respectively. Furthermore, a decrease in the degree of substitution from 1.69 to 1.27 (4-day exposure) and from 2.51 to 2.18 (12-day exposure) was observed for the respective CA samples. In contrast, CA films (DS-1.7 and DS-2.5) which were exposed to abiotic control vessels for identical time periods showed no significant changes in Mn and DS. SEM photographs of CA (DS-1.7 and DS-2.5) film surfaces after compost exposures revealed severe erosion and corresponding microbial colonization. Similar exposure times for CA films in abiotic control vessels resulted in only minor changes in surface characteristics by SEM observations. The conversion of CA DS-1.7 and DS-2.5 to CO2 was monitored by respirometry. In these studies, powdered CA was placed in a predigested compost matrix which was maintained at 53°C and 60% moisture content throughout the incubation period. A lag phase of 10- and 25-day duration for CA DS-1.7 and DS-2.5, respectively, was observed, after which the rate of degradation increased rapidly. Mineralization of exposed CA DS-1.7 and DS-2.5 powders reported as the percentage theoretical CO2 recovered reached 72.4 and 77.6% in 24 and 60 days, respectively. The results of this study demonstrated that microbial degradation of CA films exposed to aerobic thermophilic laboratory-scale compost reactors not only results in film weight loss but also causes severe film pitting and a corresponding decrease in chain Mn and degree of substitution for the residual material. Furthermore, conversions to greater than 70% of the theoretical recovered CO2 for CA (DS 1.7 and 2.5) substrates indicate high degrees of CA mineralization. © 1993 Plenum Publishing Corporation.en_US
dc.languageengen_US
dc.relation.ispartofJournal of Environmental Polymer Degradationen_US
dc.subjectBiodegradation Testingen_US
dc.subjectCellulose Acetateen_US
dc.subjectDegree Of Substitutionen_US
dc.subjectMolecular Weighten_US
dc.subjectMunicipal Solid Wasteen_US
dc.subjectPolymer Degradationen_US
dc.subjectPolymer Mineralizationen_US
dc.subjectRespirometryen_US
dc.subjectSurface Colonizationen_US
dc.titleDegradation and mineralization of cellulose acetate in simulated thermophilic compost environmentsen_US
dc.typeArticleen_US
dc.identifier.emailGu, JD: jdgu@hkucc.hku.hken_US
dc.identifier.authorityGu, JD=rp00701en_US
dc.description.naturelink_to_subscribed_fulltexten_US
dc.identifier.doi10.1007/BF01458295en_US
dc.identifier.scopuseid_2-s2.0-0027671727en_US
dc.identifier.volume1en_US
dc.identifier.issue4en_US
dc.identifier.spage281en_US
dc.identifier.epage291en_US
dc.identifier.scopusauthoridGu, JD=7403129601en_US
dc.identifier.scopusauthoridEberiel, D=6602234796en_US
dc.identifier.scopusauthoridMcCarthy, SP=35431476300en_US
dc.identifier.scopusauthoridGross, RA=7403099956en_US

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats