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Reverse osmosis (RO) membranes have been widely used in the field of membrane separation. However, most of the commercial RO membranes are fabricated based on a polysulphones- or polyethersulfone-modified polyethylene glycol terephthalate (PET) support, which are thick and exhibit poor solvent resistance. In this study, polyethylene (PE) battery membranes without any hydrophilic modification were directly used to prepare PE-RO membranes. The structures of the products were confirmed via attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. The resulting RO membrane prepared with 0.05 wt.% of trimesoyl chloride and 2 wt.% of m-phenylenediamine exhibited a water flux of 12.61 L m−2 h−1 with a desalination (NaCl) rate of 98.6%. The thickness of the PE-RO membrane is 80% of the thickness of the traditional RO membranes and hence has a wider application as a separation membrane. [ABSTRACT FROM AUTHOR]

Tadpole-like single-chain particle (TSCP) with a crosslinked PDMAEMA (poly(2-dimethylaminoethyl methacrylate)) chain as the head and a tethered POEGMA (oligo(ethylene glycol) monomethyl ether methacrylate) chain as the tail was fabricated by intra-chain crosslinking of PDMAEMA chain of the copolymer POEGMA-b-PDMAEMA (POD). In the selective solvent for the tail, TSCPs formed worm-like micelles, thin films and tubular vesicles in DMF/H2O (1/4, v/v). Different from the traditional one-shot response to ultrasonic treatment, the tubular vesicles underwent rapid structural transformations to spherical vesicles under gentle ultrasonic treatment and fragments under an enhanced ultrasonic treatment. The unique multi-level ultrasonic response behaviour makes the assemblies promising drug carriers featured with the remote and stepwise controlling release of drugs. [ABSTRACT FROM AUTHOR]

The photoisomerisation behaviour of Poly(N-isopropylacrylamide) end-capped with 4-propoxyazobenzene (PNIPAM-Azo-OC3H7) was studied in a conconsolvent mixture of water and dioxane. The trans-cis isomerisation rate of PNIPAM-Azo-OC3H7 was mildly affected by the solvent compositions. Interestingly, the addition of dioxane could not only change the lower critical solution temperature (LCST) of PNIPAM-Azo-OC3H7 aqueous solution but also accurately controlled the increase or decrease in the LCST during UV irradiation. The LCST change (ΔT) could be adjusted from −5.0°C to 10.0°C, which was affected by the cononsolvent type, the second solvent and polymer concentration. Transmission electron micrographs (TEMs) showed that the PNIPAM-Azo-OC3H7 solution could self-assemble into different nano-micelles in different amounts of miscible solvents. UV irradiation of PNIPAM-Azo-OC3H7 solution was found to induce different changes in particle shape and size, which in turn led to either decrease or increase in the LCST changes in this novel responsive system. Furthermore, Nile red was tested here as a fluorescence probe for photo-induced release from PNIPAM-Azo-OC3H7 micelles, and the results suggested that this polymer could be used as a hydrophobic chemotherapeutic drug carrier for controlled release. [ABSTRACT FROM AUTHOR]

Poly(ester-ether)s are biodegradable copolymers with excellent performance. These copolymers are used as scaffolds for tissue engineering and degradable materials in packaging. However, their synthesis procedures are generally tedious which restrict their widespread applications. Furthermore, the inadequate availability of their commercial monomers also hampers their production. Herein, we reported a facile strategy for the synthesis of linear and branched poly(ester-ether)s using a polyol and methyl acrylate (MA) as monomers. During the polymerisation, the vinyl bond of MA reacts with the hydroxyl groups of a polyol following an oxa-Michael polyaddition mechanism. Simultaneously, esterification takes place between the ester group of MA and polyol. As a result, poly(ester-ether)s were successfully synthesised by combining these two different types of reactions into one polymerisation system. The linear and branched structures of the products were confirmed by the nuclear magnetic resonance and triple-detector gel permeation chromatography. This work provides a facile strategy for the synthesis of poly(ester-ether)s from commercially available monomers. [ABSTRACT FROM AUTHOR]

Polymeric patchy micelles (PPMs) are nanostructures with distinct regions on their surfaces, offering unique properties for various applications. Herein, we present a straightforward method for monitoring the structure of PPMs formed via non-covalent post-assembly modification (NCPAM). By employing 1-pyrenemethylamine, a pyrene-based molecule, as both a modifier and fluorescent probe, we demonstrate that the formation of PPMs with a higher order aggregation state of pyrene induces a stronger pyrene excimer emission. This leads to variations in the excimer-to-monomer emission ratio, serving as a parameter for studying structural changes in PPMs during NCPAM. In situ monitoring of PPM formation and temperature-dependent transformations is achieved using fluorescent analytical method, providing valuable insights into their structural evolution and dynamic behaviour. This study offers a straightforward approach to understanding and controlling PPM structures, facilitating the design of advanced nanomaterials for diverse applications. [ABSTRACT FROM AUTHOR]