Matches in SemOpenAlex for { <https://semopenalex.org/work/W2139251717> ?p ?o ?g. }
Showing items 1 to 76 of
76
with 100 items per page.
- W2139251717 endingPage "8" @default.
- W2139251717 startingPage "7" @default.
- W2139251717 abstract "Two approaches for creating a new all-cellulose composite material have been studied: the biosynthesis of compartmentalised bacterial cellulose fibril aggregates and the compression moulding of commercial chemical wood pulps processed with only water. The objective was to study the structural changes during processing and the complexity of relating the mechanical properties of the final biocomposites to the nanoscale structure was highlighted.Solid-state CP/MAS 13C NMR spectroscopy was utilised to determine both the fibril aggregate width and the content of the different crystalline cellulose forms, cellulose I and cellulose II. Using this method, the quantities of hemicellulose present inside the fibre wall and localised at the fibre surfaces could be determined.The formation of cellulose fibrils was affected by the addition of hydroxyethylcellulose (HEC) to a culture medium of Acetobacter aceti, and the fibrils were coated with a thin layer of HEC, which resulted in loose bundles of fibril aggregates. The HEC coating, improved the fibril dispersion in the films and prevented fractures, resulting in a biocomposite with remarkable mechanical properties including improved strength (289 MPa), modulus (12.5 GPa) and toughness (6%).The effect of press temperature was studied during compression moulding of sulphite dissolving-grade pulps at 45 MPa. A higher press temperature yielded increases in the fibril aggregation, water resistance (measured as the water retention value) and Young’s modulus (12 GPa) in the final biocomposite. The high pressure was important for fibril aggregation, possibly including cellulose-cellulose fusion bonds, i.e., fibril aggregation in the fibre-fibre bond region. The optimal press temperature was found to be 170°C because cellulose undergoes thermal degradation at higher temperatures.The effect of hemicellulose was studied by comparing a softwood kraft paper-grade pulp with a softwood sulphite paper and a softwood sulphite dissolving-grade pulp. A significant fibril aggregation of the sulphite pulps suggested that the content and distribution of hemicellulose affected the fibril aggregation. In addition, the hemicellulose structure could influence the ability of the hemicellulose to co-aggregate with cellulose fibrils. Both sulphite pulp biocomposites exhibited Young’s moduli of approximately 12 GPa, whereas that of the kraft pulp was approximately half that value at 6 GPa. This result can be explained by a higher sensitivity to beating in the sulphite pulps.The effect of mercerisation, which introduces disordered cellulose, on the softwood sulphite dissolving-grade pulp was also studied under compression moulding at 170°C and 45 MPa. The mechanisms causing an incomplete transformation of cellulose I to II in a 12 wt% NaOH solution were discussed. The lower modulus of cellulose II and/or the higher quantity of disordered cellulose likely account for the decrease in Young’s modulus in the mercerised biocomposites (6.0 versus 3.9 GPa)." @default.
- W2139251717 created "2016-06-24" @default.
- W2139251717 creator A5035770108 @default.
- W2139251717 creator A5037674191 @default.
- W2139251717 creator A5040285392 @default.
- W2139251717 creator A5069406137 @default.
- W2139251717 creator A5079322514 @default.
- W2139251717 creator A5088210859 @default.
- W2139251717 date "2009-01-01" @default.
- W2139251717 modified "2023-09-27" @default.
- W2139251717 title "BIOMIMETIC DESIGN OF CELLULOSE-BASED NANOSTRUCTURED COMPOSITES USING BACTERIAL CULTURES" @default.
- W2139251717 hasPublicationYear "2009" @default.
- W2139251717 type Work @default.
- W2139251717 sameAs 2139251717 @default.
- W2139251717 citedByCount "2" @default.
- W2139251717 countsByYear W21392517172015 @default.
- W2139251717 crossrefType "journal-article" @default.
- W2139251717 hasAuthorship W2139251717A5035770108 @default.
- W2139251717 hasAuthorship W2139251717A5037674191 @default.
- W2139251717 hasAuthorship W2139251717A5040285392 @default.
- W2139251717 hasAuthorship W2139251717A5069406137 @default.
- W2139251717 hasAuthorship W2139251717A5079322514 @default.
- W2139251717 hasAuthorship W2139251717A5088210859 @default.
- W2139251717 hasConcept C104779481 @default.
- W2139251717 hasConcept C127413603 @default.
- W2139251717 hasConcept C159985019 @default.
- W2139251717 hasConcept C185592680 @default.
- W2139251717 hasConcept C192562407 @default.
- W2139251717 hasConcept C27523624 @default.
- W2139251717 hasConcept C2777869788 @default.
- W2139251717 hasConcept C2779251873 @default.
- W2139251717 hasConcept C2779477270 @default.
- W2139251717 hasConcept C42360764 @default.
- W2139251717 hasConcept C55493867 @default.
- W2139251717 hasConceptScore W2139251717C104779481 @default.
- W2139251717 hasConceptScore W2139251717C127413603 @default.
- W2139251717 hasConceptScore W2139251717C159985019 @default.
- W2139251717 hasConceptScore W2139251717C185592680 @default.
- W2139251717 hasConceptScore W2139251717C192562407 @default.
- W2139251717 hasConceptScore W2139251717C27523624 @default.
- W2139251717 hasConceptScore W2139251717C2777869788 @default.
- W2139251717 hasConceptScore W2139251717C2779251873 @default.
- W2139251717 hasConceptScore W2139251717C2779477270 @default.
- W2139251717 hasConceptScore W2139251717C42360764 @default.
- W2139251717 hasConceptScore W2139251717C55493867 @default.
- W2139251717 hasIssue "2" @default.
- W2139251717 hasLocation W21392517171 @default.
- W2139251717 hasOpenAccess W2139251717 @default.
- W2139251717 hasPrimaryLocation W21392517171 @default.
- W2139251717 hasRelatedWork W1502203369 @default.
- W2139251717 hasRelatedWork W1967581757 @default.
- W2139251717 hasRelatedWork W1974285150 @default.
- W2139251717 hasRelatedWork W2033785893 @default.
- W2139251717 hasRelatedWork W2075491569 @default.
- W2139251717 hasRelatedWork W2080824677 @default.
- W2139251717 hasRelatedWork W2089084999 @default.
- W2139251717 hasRelatedWork W2090768132 @default.
- W2139251717 hasRelatedWork W2492336212 @default.
- W2139251717 hasRelatedWork W2524058311 @default.
- W2139251717 hasRelatedWork W2587768664 @default.
- W2139251717 hasRelatedWork W2791567838 @default.
- W2139251717 hasRelatedWork W2889932479 @default.
- W2139251717 hasRelatedWork W2899008428 @default.
- W2139251717 hasRelatedWork W2907467153 @default.
- W2139251717 hasRelatedWork W2943085652 @default.
- W2139251717 hasRelatedWork W3011329516 @default.
- W2139251717 hasRelatedWork W3135026219 @default.
- W2139251717 hasRelatedWork W3158729797 @default.
- W2139251717 hasRelatedWork W83408329 @default.
- W2139251717 hasVolume "50" @default.
- W2139251717 isParatext "false" @default.
- W2139251717 isRetracted "false" @default.
- W2139251717 magId "2139251717" @default.
- W2139251717 workType "article" @default.