PhD Thesis-Saeed Fathi - 2011- Final Version.pdf (22.93 MB)
Download fileFundamental investigation on inkjet printing of reactive nylon materials
thesis
posted on 2011-01-25, 09:16 authored by Saeed FathiSeveral additive manufacturing processes have been developed for plastic parts.
However, there is an ongoing interest to increase the functionality of these parts
which are mainly considered as prototypes due to the material and process
limitations. This research investigated a novel additive approach for producing a
functional engineering plastic, nylon 6. The idea was to combine inkjet printing
technology and anionic polymerisation of caprolactam by depositing mixtures of
caprolactam with activator and catalyst on top of each other under the appropriate
conditions. An experimental setup was
integrated based on two identical jetting assemblies with pneumatic and thermal
control, synchronised with a deposition system for the reaction of the mixtures upon
radiation heating. Different offline material characterisation and inline process
monitoring methods were employed to obtain an understanding of the material
behaviour at each stage of the research. These included the use of high speed
imaging, fluorescent microscopy, particle tracking and image analysis tools. Samples were monitored before and after the drop-on-drop
deposition and radiation heating, and then assessed by thermal analysis to find
the appropriate conditions for the reaction. It was found that although some
monomer conversion was achieved, the rates were much less than with the bulk
polymerisation approach. Jetting of thousands of tiny droplets in air could have
resulted in a very high monomer deactivation. This highlighted the importance of the
environment as a more significant parameter for jetting of nylon 6 compared with the
conventional method.
History
School
- Mechanical, Electrical and Manufacturing Engineering
Publisher
Loughborough UniversityRights holder
© Saeed FathiPublication date
2011Notes
A Doctoral Thesis. Submitted in partial fulfillment of the requirements for the award of Doctor of Philosophy of Loughborough University.EThOS Persistent ID
uk.bl.ethos.542586Language
- en
Supervisor(s)
Phil DickensQualification name
- PhD
Qualification level
- Doctoral