Abstract
Highly porous structures made by foam forming technique
from natural fibres have several possible future
applications. Among these are acoustic materials or
cushioning elements in packages. Certain compression
strength level is needed in both applications. We
investigated the effect of fibre length distribution on
the compression strength using hemp bast fibres as long
fibres, softwood cellulose as medium length fibres and
lignin-rich fines made from spruce wood as the micro
fibre component. In addition wooden-like hemp shives were
used. The fibre mixtures were foamed with two different
types of surfactants: an anionic sodium dodecyl sulphate
(SDS) surfactant that has a neutral effect on material
bonding and a non-ionic polyvinyl alcohol (PVA)
surfactant that enhances bonding.
Lignin-rich fines improved the compression strength in
all fibre mixtures when SDS was used as the foaming
surfactant. The significance of fines addition was minor
with materials foamed with PVA. Long hemp bast fibres
decreased the compression strength with both surfactants.
Addition of stiff hemp shives with bonding enhancing
surfactant resulted in good compression strength.
Overall, surfactant selection between a bonding and
non-bonding one had a larger effect on the compression
strength compared to the selected fibre types and fibre
mixtures.
Hemp is one of the annual crops, which use has increased
in different applications in recent years. The
traditional use of hemp fibre is in textiles, but the use
in different composites, nonwovens and even medical
applications has increased. Hemp fibre in plant is
located in stem and it's mechanical performance is
comparable to glass fibre properties making it good
choice for reinforcement in biocomposites. We studied
hemp fibre and shive in different potential applications
from composites to non-woven structures and hemp based
nanocelluloses in order to find potential novel uses for
hemp.
According to the preliminary results hemp fibre and
shives are potential raw materials in natural-fibre
plastic composites. In strength point of view it competes
with other cellulose based composites and gives new
visual design aspects for the material. Nanocellulose
made of hemp fibres formed highly viscous hydrogel, which
is attractive as a reinforcing component, rheology
modifier and film forming material. Their characteristics
can be further improved by chemical pre-treatments. Hemp
based nanocelluloses have similar or even better
characteristics compared to the commercial and wood-based
nanocelluloses.
Original language | English |
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Title of host publication | Book of Abstracts |
Publication status | Published - 2016 |
Event | Concreso Iberoamericano De Investigacion En Celulosa Y Paperl - Iberoamerican Congress on Pulp and Paper Research, CIADICYP 2016: IX Iberoamerican Congress on Pulp and Paper Research - Espoo, Finland Duration: 4 Sept 2016 → 8 Sept 2016 |
Conference
Conference | Concreso Iberoamericano De Investigacion En Celulosa Y Paperl - Iberoamerican Congress on Pulp and Paper Research, CIADICYP 2016 |
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Abbreviated title | CIADICYP 2016 |
Country/Territory | Finland |
City | Espoo |
Period | 4/09/16 → 8/09/16 |
Keywords
- foam forming
- porous fibre structures
- hemp
- biocomposites
- biopolymers
- nanocellulose
- compression strength