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Porous liquids combine the properties of a porous solid with those of a liquid, creating a porous flowable media. Since their discovery, these materials have gathered widespread interest within the scientific community, with substantial numbers of new systems being discovered, often with a focus on increasing the pore volume and gas capacity. Which begs the question, what does the future hold for porous liquids? Recently, the first examples of photoresponsive porous liquids have emerged, allowing changes in porosity to be observed under UV irradiation. Here, we expand on our previous report of photoresponsive porous liquids and explore the conceptualisation of responsive porous liquids and how these materials could be developed with the ability to respond to light, thereby offering a potential mechanism of controllable uptake and release in these systems. This concept article summarises different approaches that could be used to incorporate a photoresponse in a porous liquid before discussing recently reported systems, alongside important factors to consider in their design. Finally, by taking inspiration from the methods used to translate porous solids into the liquid state, combined with the field of photoresponsive materials, we discuss potential strategies that could be employed to realise further examples of photoresponsive porous liquids. [ABSTRACT FROM AUTHOR]

Five nitrogen sources (glycine, β‐alanine, urea, melamine and nicotinamide) and three heating methods (thermal, monomodal microwave and multimodal microwave) are used to prepare nitrogen‐doped Starbons® derived from starch. The materials are initially produced at 250–300 °C (SNx300y), then heated in vacuo to 800 °C to produce nitrogen‐doped SNx800y's. Melamine gives the highest nitrogen incorporation without destroying the Starbon® pore structure and the microwave heating methods give higher nitrogen incorporations than thermal heating. The carbon dioxide adsorption capacities of the nitrogen‐doped Starbons® determined gravimetrically, in many cases exceed those of S300 and S800. The carbon dioxide, nitrogen and methane adsorption isotherms of the most promising materials are measured volumetrically. Most of the nitrogen‐doped materials show higher carbon dioxide adsorption capacities than S800, but lower methane and nitrogen adsorption capacities. As a result, the nitrogen‐doped Starbons® exhibit significantly enhanced carbon dioxide versus nitrogen and methane versus nitrogen selectivities compared to S800. [ABSTRACT FROM AUTHOR]

Crystalline porous organic salts (CPOS) are a subclass of molecular crystals. The low solubility of CPOS and their building blocks limits the choice of crystallisation solvents to water or polar alcohols, hindering the isolation, scale‐up, and scope of the porous material. In this work, high throughput screening was used to expand the solvent scope, resulting in the identification of a new porous salt, CPOS‐7, formed from tetrakis(4‐sulfophenyl)methane (TSPM) and tetrakis(4‐aminophenyl)methane (TAPM). CPOS‐7 does not form with standard solvents for CPOS, rather a hydrated phase (Hydrate2920) previously reported is isolated. Initial attempts to translate the crystallisation to batch led to challenges with loss of crystallinity and Hydrate2920 forming favorably in the presence of excess water. Using acetic acid as a dehydrating agent hindered formation of Hydrate2920 and furthermore allowed for direct conversion to CPOS‐7. To allow for direct formation of CPOS‐7 in high crystallinity flow chemistry was used for the first time to circumvent the issues found in batch. CPOS‐7 and Hydrate2920 were shown to have promise for water and CO2 capture, with CPOS‐7 having a CO2 uptake of 4.3 mmol/g at 195 K, making it one of the most porous CPOS reported to date. [ABSTRACT FROM AUTHOR]

The synthesis of a new porous organic cage decorated with isopropyl moieties (CC21) was achieved from the reaction of triformylbenzene and an isopropyl functionalised diamine. Unlike structurally analogous porous organic cages, its synthesis proved challenging due to competitive aminal formation, rationalised using control experiments and computational modelling. The use of an additional amine was found to increase conversion to the desired cage. [ABSTRACT FROM AUTHOR]

Porous materials are the subject of extensive research because of potential applications in areas such as gas adsorption and molecular separations. Until recently, most porous materials were solids, but there is now an emerging class of materials known as porous liquids. The incorporation of intrinsic porosity or cavities in a liquid can result in free‐flowing materials that are capable of gas uptakes that are significantly higher than conventional non‐porous liquids. A handful of porous liquids have also been investigated for gas separations. Until now, the release of gas from porous liquids has relied on molecular displacement (e.g., by adding small solvent molecules), pressure or temperature swings, or sonication. Here, we explore a new method of gas release which involves photoisomerisable porous liquids comprising a photoresponsive MOF dispersed in an ionic liquid. This results in the selective uptake of CO2 over CH4 and allows gas release to be controlled by using UV light. [ABSTRACT FROM AUTHOR]

The discrete molecular nature of porous organic cages (POCs) has allowed us to direct the formation of crystalline materials by crystal engineering. It has also been possible to create porous amorphous solids by deliberately disrupting the crystalline packing, either with chemical modification or by processing. More recently, organic cages were used to form isotropic porous liquids. However, the connection between solid and liquid states of POCs, and the glass state, are almost completely unexplored. Here, we investigate the melting and glass-forming behaviour of a range of organic cages, including both shape-persistent POCs formed by imine condensation, and reduced and synthetically post-modified amine POCs that are more flexible and lack shape-persistence. The organic cages exhibited melting and quenching of the resultant liquids provides molecular glasses. One of these molecular glasses exhibited improved gas uptake for both CO2 and CH4 compared to the starting amorphous cage. In addition, foaming of the liquid in one case resulted in a more stable and less soluble glass, which demonstrates the potential for an alternative approach to forming materials such as membranes without solution processing. [ABSTRACT FROM AUTHOR]

Control of pore window size is the standard approach for tuning gas selectivity in porous solids. Here, we present the first example where this is translated into a molecular porous liquid formed from organic cage molecules. Reduction of the cage window size by chemical synthesis switches the selectivity from Xe‐selective to CH4‐selective, which is understood using 129Xe, 1H, and pulsed‐field gradient NMR spectroscopy. [ABSTRACT FROM AUTHOR]

A reaction manifold has been discovered in which the chemoselectivity can be altered by switching between neat milling and liquid assisted grinding (LAG) with polar additives. After investigation of the reaction mechanism, it has been established that this switching in reaction pathway is due to the neat mechanochemical conditions exhibiting different kinetics for a key step in the transformation. This proof of concept study demonstrates that mechanochemistry can be used to trap the kinetic product of a reaction. It is envisaged that, if this concept can be successfully applied to other transformations, novel synthetic processes could be discovered and known reaction pathways perturbed or diverted. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is threefold; first, to give a background to the security of payment problem in the New South Wales construction industry and the problem giving rise to the Building and Construction Industry Security of Payment Amendment Act 2010 (NSW) ("2010 Amendment Act"); second, to provide an analysis of the operation of the 2010 Amendment Act; and finally, to address the main implications of the amendments for the three parties involved, namely the claimant, the respondent and the "Principal contractor". Design/methodology/approach – A review of the relevant literature was undertaken on the security of payment problem in the NSW construction industry and the problem giving rise to the 2010 Amendment Act. A "black-letter" approach is adopted to analyse and explain the provisions contained in the 2010 Amendment Act. At the time of writing, no case law relevant to the amendments had been published. Findings – The amendments brought about by the 2010 Amendment Act add appreciably to the scope of the Building and Construction Industry Security of Payment Act 1999 (NSW). The effect of the procedure under the 2010 Amendment Act is similar to that under the Contractors Debts Act 1997 (NSW). The 2010 Amendment Act enables a claimant to "freeze" money in the hands of the Principal contractor pending an adjudication, thereby increasing the chance of recovery of the adjudicated amount by the claimant. If, under this new procedure, the Principal contractor fails to "freeze" the monies, the Principal contractor will be liable (along with the respondent) for the amount owed to the claimant. There is a potential for the amendments to be used unfairly by claimants to coerce settlement of unmeritorious payment claims. Originality/value – The analysis of the 2010 Amendment Act presented in this paper may be of interest in international jurisdictions where statutory adjudication for the construction industry has been introduced or is being contemplated. [ABSTRACT FROM AUTHOR]