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The use of chemometric techniques with spectral data for sorting plastics to improve recycling rates have gained more attention in recent years. However, insufficient representation of polymer spectra in spectral databases has been one of the barriers to the further development of these techniques. This work aims to develop a polymer spectra dataset that builds upon existing spectral databases on two fronts. Firstly, the data collected includes Laser-induced Breakdown Spectroscopy (LIBS) data in addition to more commonly available Infrared (IR) and Raman data. Secondly, the dataset includes unaged and weathered conditions of the same sample. In total, the dataset includes 732 spectra, with the LIBS, IR and Raman spectra of 122 unique samples, both before and after accelerated weathering. The data collected were qualitatively analyzed and visualized. Further work will explore the effect of using hybrid spectroscopic methods on chemometrics analysis results.

Nanomaterials are becoming widely used in areas such as biomedical applications, food, environmental protection, energy production, information technology and agriculture. As such, more research has been conducted on their synthesis and manufacturing from a variety of feedstocks. However, concerns regarding their impact on human health and the environment leads researchers to conduct a variety of ‘sustainability’assessments. The purpose of this paper was to review the current opinion of sustainability assessments concerning nanomaterials. Major assessment tools were reviewed including life cycle assessment, risk assessment and multi-criteria decision analysis, along with subcategories. The review found that each assessment tool did positively contribute to sustainability assessments, but each also had drawbacks of varying degrees. In particular, multi-criteria decision analysis provides the most relevant tool for conducting a sustainability assessment as it can handle criteria of any typology and provide multiple types of decision recommendations, including rankings, scores and classifications.

Bio-based thermoset polymers were produced from epoxidised waste vegetable oils (WVOs) cured with anhydrides at different molar ratios. Properties were compared to analogues produced with neat oil and diglycidyl ether of bisphenol A as a feedstock. The thermal stability proved to be affected by the molar ratio, and the use of feedstock from waste oil resulted in no effect on this property. A dynamic mechanical analysis has shown that higher concentrations of anhydride enhance the storage modulus, glass transition temperature (up to 42·5°C) and cross-link density. The frying process proved to play a minor role in tuning the dynamic mechanical properties. However, the contribution of the anhydride was demonstrated to be significant enough to mitigate the losses caused by the waste oil, as shown statistically in a design of experiment study. All formulations were chemically resistant to aqueous, organic and acidic media. The identification of the effects of critical parameters on the properties of WVO-based thermosets enables the further production of polymers from waste streams.

Bacterial and fungal degradation of wheat straw has become intensively scrutinised in recent years because of the growing interest in procuring useful feedstocks and chemicals from lignocellulosic sources. Typically, after the extraction of valuable sugars and phenolics, significant quantities of solid biomass remain as waste. In this work, it has been shown that the leftover fermented wheat straw can be successfully used to reinforce epoxy resins, providing better strength properties compared to non-degraded straw. A 12% and a 22% increase in Young’s modulus and ultimate tensile strength respectively were observed for degraded wheat straw/epoxy composites compared to composites containing non-degraded straw. The improvement in mechanical strength is explained in terms of the structural and morphological transformations that occurred in the fibres during the fermentation process. The opportunity to use degraded natural fibres in the manufacturing of composites, in addition to the production of chemicals from lignocellulosic feedstocks, looks promising for improving biorefinery economics further.

Composites offer high strength and stiffness at a lower density compared to other structural materials, therefore are of growing use to a variety of lightweight structures in order to reduce emissions and improve performance. However, traditional composites have the highest embodied carbon content of all engineering materials with limited methods of recycling. Therefore moving composites to a biobased sourcing can have a large impact in the eco-footprint of these materials. 2-Methoxy-4-vinylphenol has previously been shown to be sustainably biosourced from microbial degradation of lignin and has been termed ‘biostyrene’. In this work, the authors investigate the use of 2-methoxy-4-vinylphenol analogues as a replacement for styrene as a reactive thinner for thermoset polyester, which is commonly used in fibreglass composite. 2-Methoxy-4-vinylphenyl acetate and 2-methoxy-4-vinylphenyl oleate were synthesised and along with unmodified 2-methoxy-4-vinylphenol and 1,2-dimethoxy-4-vinylbenzene (3,4-dimethoxystyrene) were compared to styrene in typical polyester formulations. The mechanical properties by way of tensile tests and water-uptake tests and thermal properties by way of dynamic scanning calorimetry were used for comparison. Overall, the solubility issues were apparent using the biostyrenes, however, blends of biostyrenes with styrene of up to 50% showed no statistical difference with pure styrene in properties and so may be a viable styrene replacement in polyester used for fibreglass.

Fuel cell technology continues to advance and offers to be a potentially promising solution to many energy needs. Of particular interest are manufacturing techniques to improve performance and decrease overall cost. For catalyst deposition on the membrane electrode assembly (MEA), there are a number of techniques that have been used in the past decades. This paper aims to review many of these main techniques that have been published to show the wide variety of catalyst deposition methods.

Fuel cell technology continues to advance and offers to be a potentially promising solution to many energy needs. Of particular interest are manufacturing techniques to improve performance and decrease overall cost. For catalyst deposition on the membrane electrode assembly (MEA), there are a number of techniques that have been used in the past decades. This paper aims to review many of these main techniques that have been published to show the wide variety of catalyst deposition methods.