10Membranes with more resilience to abrasive wear are highly desired in water treatment, 11 especially for seawater desalination. Nanocomposite poly(vinylidene fluoride) 12 (PVDF)/nanoclay membranes were prepared by phase inversion and then tested for abrasion 13 resistance. Their material properties were characterized using Fourier-transform infrared 14 spectroscopy (FTIR), thermogravimetric analysis (TGA), tensile testing, scanning electron 15 microscopy (SEM) and energy dispersive spectroscopy (EDS). Nanoclay Cloisite ® 15A was 16 utilised as the inorganic nanoparticle incorporated into PVDF. FTIR results showed a shifting 17 of the PVDF crystalline phase from Į to ȕ thus indicating that the nanoclay altered the PVDF 18 host material's structure and mechanical properties in terms of stiffness and toughness. Water 19 permeation test showed that nanoclay at low concentration tended to reduce water flux. All 20 nanocomposite membranes, with between 1 wt% and 5 wt% initial nanoclay loading, were 21 more abrasion resistant than the control PVDF membrane. However, the 1 wt% exhibited 22 superior resistance, lasting two times longer than the reference PVDF membrane under the 23 same abrasive condition. The 1 wt% nanoclay membrane appeared less abraded by SEM 24 observation, while also having the greatest tensile strength improvement (from 4.5 MPa to 4.9 25 MPa). This membrane also had the smallest agglomerated nanoclay particle size and highest 26 toughness compared to the higher nanoclay content membranes. Nanoclays are therefore 27 useful for improving abrasion resistance of PVDF membranes, but optimal loadings are 28 essential to avoid losing essential mechanical properties. 29 30

A new method of measuring the properties of hollow fibre membranes for modelling purposes was developed. Measuring the gas permeability as a function of membrane length and extrapolating to zero length provided enough membrane material information for modelling the flux. These values resulted in the predicted Vacuum Membrane Distillation (VMD) flux within the experimental errors (±5%) for different velocities. The predicted results at different temperatures were mostly within the experimental variation range. However, the error (<10%) was greater at the highest temperature tested, perhaps due to water evaporation in the feed tank. Additionally both the modelling and experimental results show that the flux in VMD was independent of the module packing density under the presented conditions. The results also show that the mathematical model predictions agree well with the experimental results of short experimental duration (1 -2 h).

A standard protocol for the parallel optimization of Reversible Addition -Fragmentation Chain Transfer (RAFT) polymerization conditions using an automated synthesizer is described in this report. Experimental design based on the knowledge obtained from previous screening experiments and the literature is the most effective initial step of the High-Throughput Experimentation (HTE) cycle. In this paper, the polymerization procedure is explained step-by-step including preparation of stock solutions, inertization of the reactors and synthesizer environment, liquid transfers to or from the reactor vessels including sampling, as well as termination of the polymerization. Automated characterization techniques for the determination of monomer conversion and the molecular weight distribution of the polymers are discussed to complete the HTE cycle. Consequently, analysis of the data obtained from parallel screening of reactions and their products will result in the design of the next experimental cycle.

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A combination of increasingly stringent environmental legislation and economic competition is driving industrial processes further and further towards the three “E”s of chemical manufacture: economy, efficiency and environmental impact. In this paper, we present a novel aqueous method for the synthesis of polyimides. The products resulting from this process perform similarly, through both qualitative and quantitative comparisons, to those conventionally produced using high boiling dipolar aprotic solvent. This highly efficient one-pot method potentially provides economic advantage through low solvent cost and environmental impact benefit from the manageable aqueous waste.