Mechanical properties of paper made from dopamine modified wood-fibres and fibrils
Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesisAlternative title
Mekaniska egenskaper hos papper gjorda av dopamin modifierade träfibrer och fibriller (Swedish)
The objective of this project is to clarify whether dopamine (DOPA) can be used to improve the mechanical properties of paper used for high voltage electrical insulation applications. Demands on mechanical strength for solid insulations in power transformers are high due to increasing voltage levels and their long lifetimes. The increased understanding of the important role DOPA plays for the mechanical stability of mussel byssus has inspired research on DOPA modified materials with improved wet strength.
Carboxymethylated cellulose fibres (CMC) and fibrils with a charge of ≈570 µmol/g were modified with DOPA using carbodiimide chemistry. Two different methods were used to prepare DOPA modified paper; 1) DOPA modified pulp 2) unmodified pulp with DOPA modified fibrils as an additive. The dry and wet strength of the papers were characterized with tensile testing and there was no improvement in dry strength of the papers based on DOPA modified fibres. The papers with 5wt% DOPA modified fibrils as an additive showed both improved dry strength (105.0 Nm/g compared to 68,2 Nm/g for the reference) and wet strength. The use of fibrils as an additive has the advantage that it is easier to implement in an industrial process compared to modifying the whole raw material and the cost will be naturally much lower.
Place, publisher, year, edition, pages
2016. , 36 p.
Dopamine, metal coordination, biomaterials, nano cellulose, electrical insulation
IdentifiersURN: urn:nbn:se:kth:diva-190921OAI: oai:DiVA.org:kth-190921DiVA: diva2:953743