PRISM: Polymer, Recycling, Industrial, Sustainability and Manufacturing Institute (Midlands)
https://research.thea.ie/handle/20.500.12065/2434
2024-03-29T08:22:43ZTargeting bacterial nanocellullose properties through tailored downstream techniques
https://research.thea.ie/handle/20.500.12065/4771
Targeting bacterial nanocellullose properties through tailored downstream techniques
Da Silva Pereira, Everton Henrique; Mojicevic, Marija; Tas, Cunety Erdinc; Lanzagorta Garcia, Eduardo; Fournet, Margaret Brennan
Bacterial nanocellulose (BNC) is a biodegradable polysaccharide with unique properties that make it an attractive material for various industrial applications. This study focuses on the strain Komagataeibacter medellinensis ID13488, a strain with the ability to produce high yields of BNC under acidic growth conditions and a promising candidate to use for industrial production of BNC. We conducted a comprehensive investigation into the effects of downstream treatments on the structural and mechanical characteristics of BNC. When compared to alkaline-treated BNC, autoclave-treated BNC exhibited around 78% superior flexibility in average, while it displayed nearly 40% lower stiffness on average. An SEM analysis revealed distinct surface characteristics, indicating differences in cellulose chain compaction. FTIR spectra demonstrated increased hydrogen bonding with prolonged interaction time with alkaline solutions. A thermal analysis showed enhanced thermal stability in alkaline-treated BNC, withstanding temperatures of nearly 300 °C before commencing degradation, compared to autoclaved BNC which starts degradation around 200 °C. These findings provide valuable insights for tailoring BNC properties for specific applications, particularly in industries requiring high purity and specific mechanical characteristics.
2024-03-02T00:00:00ZExploring microorganisms from plastic-polluted sites:unveiling plastic degradation and PHA production potential
https://research.thea.ie/handle/20.500.12065/4757
Exploring microorganisms from plastic-polluted sites:unveiling plastic degradation and PHA production potential
Garza Herrera, Diana A.; Mojicevic, Marija; Pantelic, Brana; Joshi, Akanksha; Torres, Cristiana; Freitas, Filomena; Murray, Patrick; Nikodinovic-Runic, Jasmina; Brennan Fournet, Margaret
The exposure of microorganisms to conventional plastics is a relatively recent occurrence,
affording limited time for evolutionary adaptation. As part of the EU-funded project BioICEP,
this study delves into the plastic degradation potential of microorganisms isolated from sites with
prolonged plastic pollution, such as plastic-polluted forests, biopolymer-contaminated soil, oilcontaminated
soil, municipal landfill, but also a distinctive soil sample with plastic pieces buried three
decades ago. Additionally, samples from Arthropoda species were investigated. In total, 150 strains
were isolated and screened for the ability to use plastic-related substrates (Impranil dispersions,
polyethylene terephthalate, terephthalic acid, and bis(2-hydroxyethyl) terephthalate). Twenty isolates
selected based on their ability to grow on various substrates were identified as Streptomyces, Bacillus,
Enterococcus, and Pseudomonas spp. Morphological features were recorded, and the 16S rRNA
sequence was employed to construct a phylogenetic tree. Subsequent assessments unveiled that 5
out of the 20 strains displayed the capability to produce polyhydroxyalkanoates, utilizing pre-treated
post-consumer PET samples. With Priestia sp. DG69 and Neobacillus sp. DG40 emerging as the most
successful producers (4.14% and 3.34% of PHA, respectively), these strains are poised for further
utilization in upcycling purposes, laying the foundation for the development of sustainable strategies
for plastic waste management.
2023-12-03T00:00:00ZRheological behaviour of ABS/metal composites with improved thermal conductivity for additive manufacturing
https://research.thea.ie/handle/20.500.12065/4756
Rheological behaviour of ABS/metal composites with improved thermal conductivity for additive manufacturing
Moritz, Vicente F.; Prévost, Harald; Crespo, Janaina S.; Ferreira, Carlos A.; Devine, Declan M.
Metal-reinforced polymer composites are suitable materials for applications requiring special
thermal, electrical or magnetic properties. Three-dimensional printing technologies enable these
materials to be quickly shaped in any design directly and without the need for expensive moulds.
However, processing data correlating specific information on how the metal particles influence the
rheological behaviour of such composites is lacking, which has a direct effect on the processability
of these composites through melt processing additive manufacturing. This study reports the compounding
and characterisation of ABS composites filled with aluminium and copper particulates.
Experimental results demonstrated that the tensile modulus increased with the incorporation of metal
particles; however, there was also an intense embrittling effect. Mechanical testing and rheological
analysis indicated poor affinity between the fillers and matrix, and the volume fraction proved
to be a crucial factor for complex viscosity, storage modulus and thermal conductivity. However,
a promising set of properties was achieved, paving the way for polymer–metal composites with
optimised processability, microstructure and properties in melt processing additive manufacturing
2023-11-17T00:00:00ZMethods of Characterization of 3-Printed Objects
https://research.thea.ie/handle/20.500.12065/4749
Methods of Characterization of 3-Printed Objects
Chen, Yuanyan
Gupta, Ram G.
The popularity of 3D printers has increased in the past decade, partially attributed to
the expiration of significant patents and the availability of cost-effective equipment.
The utilisation of 3D printing technology offers numerous benefits, including cost
efficiency, expedited prototyping, minimised waste production, the ability to create
lightweight structures, and decreased energy consumption, among others. According
to a recent study, the global market for 3D printing products and services reached
an estimated value of approximately 12.6 billion USD in the year 2020. Projections
indicate that this market is poised to have a compound annual growth rate of 17%
throughout the period spanning 2020 to 2023 [1]. The utilisation of 3D printing technology
has been observed in various domains, including but not limited to medical
devices and the automobile industry, electronics sector, construction field, and
aerospace sector. This chapter will elucidate the primary techniques employed for
characterising three-dimensional printed objects.
2024-01-01T00:00:00Z