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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]

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]

Anionic hybrid copolymerization (AHcP) of cyclic and vinyl monomers provides a powerful strategy to synthesize biodegradable heteropolymers. However, transesterification between comonomeric units often happens making the mechanism complex. Here, AHcP of N,N‐dimethylacrylamide (DMA) with ε‐caprolactone (CL) is investigated at 25 °C, where DMA does not have ester group so that no transesterification between DMA and CL units happens. Nuclear magnetic resonance (NMR) and matrix‐assisted laser desorption/ionization time of flight mass spectrometry measurements reveal that DMA and CL units are randomly distributed in the resulted polymer. Differential scanning calorimetry measurements show that the copolymer has only one glass transition temperature (Tg). Thermogravimetric analysis demonstrates the copolymer has a single‐stage decomposition from 255 to 425 °C, which is between those of the corresponding homopolymers. Thes facts further indicate that the copolymer is random. This study clearly demonstrates that AHcP takes place regardless of transesterification though it may have some effects. [ABSTRACT FROM AUTHOR]

In the copolymerization of acrylamide (Am) and hydroxyethyl acrylate (HEA), the initial product is a carbon chain polymer with hydroxyl and amide side groups. However, in the present work, these two conventional vinyl monomers are combined into a degradable heterochain copolymer by using a phosphazene base, t‐BuP4, as a catalyst. NMR not only confirms that the backbone of the resulting copolymer is composed of ester–ether units and amide units but also suggests that the resulted secondary amide group retains an active hydrogen and can further react with another olefin, which would result in branching or gelation. Thermogravimetric analysis (TGA) shows a signal indicating decomposition at 205–509 °C, verifying the uniform composition of the sample. More interestingly, the synthesized copolymer can dissolve in water and exhibits aggregation‐enhanced emission (AEE). Additionally, the aqueous copolymer solution has a high selectivity and sensitivity for Ba2+, Fe2+, and Fe3+ cations. Hence, it is believed that this method for constructing degradable polymers may offer innovative insights into polymer synthesis and application. [ABSTRACT FROM AUTHOR]