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Polymer electrolytes continue to offer the opportunity for safer, high-performing next-generation battery technology. The benefits of a polymeric electrolyte system lie in its ease of processing and flexibility, while ion transport and mechanical strength have been highlighted for improvement. This report discusses how factors, specifically the chemistry and structure of the polymers, have driven the progression of these materials from the early days of PEO. The introduction of ionic polymers has led to advances in ionic conductivity while the use of block copolymers has also increased the mechanical properties and provided more flexibility in solid polymer electrolyte development. The combination of these two, ionic block copolymer materials, are still in their early stages but offer exciting possibilities for the future of this field. [ABSTRACT FROM AUTHOR]

[Display omitted] • One-pot sequential addition RAFT polymerization of quasi-block copolymers. • Very good polymer control achieved with high monomer conversions. • Light initiated chain extensions ease acrylate polymerization. • Monomer sequence has influence on thermal characteristics. • Phase morphology maintained in quasi-block copolymers. This works reports a novel approach at synthesising ionic quasi-block copolymers derived from a polystyrene- block -poly polyethylacrylate(butylimidazolium)bis(trifluromethanesulfonyl)imide block copolymer using a 'one-pot' RAFT polymerization technique. Three different quasi-block copolymer were synthesised following a sequential additional method whereby composition was altered through changing the order of monomer addition and the level of monomer conversion. The new quasi-block copolymers were analysed compositionally, thermally and through phase morphology to assess the impact this new synthesis has on polymer control and to determine whether block behaviour is maintained. The results suggests these new quasi-block behave similarly to block copolymers regarding phase behaviour, while offering potential for increased sustainability in the synthesis. [ABSTRACT FROM AUTHOR]

Clinical studies have validated that antiretroviral (ARV) drugs can serve as an HIV pre-exposure prophylactic (PrEP) strategy. Dosing adherence remains a crucial factor determining the final efficacy outcomes, and both long-acting implants and injectable depot systems are being developed to improve patient adherence. Here, we describe an injectable depot platform that exploits a new mechanism for both formation and controlled release. The depot is a polymeric prodrug synthesized from monomers that incorporate an ARV drug tenofovir alafenamide (TAF) with degradable linkers that can be designed to control release rates. The prodrug monomers are synthetically incorporated into homopolymer or block designs that exhibit high drug weight percent (wt%) and also are hydrophobized in these prodrug segments to drive depot formation upon injection. Drug release converts those monomers to more hydrophilic pendant groups via linker cleavage, and as this drug release proceeds, the polymer chains losing hydrophobicity are then disassociated from the depot and released over time to provide a depot dissolution mechanism. We show that long-acting TAF depots can be designed as block copolymers or as homopolymers. They can also be designed with different linkers, for example with faster or slower degrading p -hydroxybenzyloxycarbonyl (Benzyl) and ethyloxycarbonyl (Alkyl) linkers, respectively. Diblock designs of p(glycerol monomethacrylate)- b -p(Alkyl-TAF-methacrylate) and p(glycerol monomethacrylate)- b -p(Benzyl-TAF-methacrylate) were first characterized in a mouse subcutaneous injection model. The alkylcarbamate linker design (TAF 51 wt%) showed excellent sustained release profiles of the key metabolite tenofovir (TFV) in skin and plasma over a 50-day period. Next, the homopolymer design with a high TAF drug wt% of 73% was characterized in the same model. The homopolymer depots with p(Alkyl-TAFMA) exhibited sustained TFV and TAF release profiles in skin and blood over 60 days, and TFV-DP concentrations in peripheral blood mononuclear cells (PBMC) were found to be at least 10-fold higher than the clinically suggested minimally EC90 protective concentration of 24 fmol/106 cells. These are the first reports of sustained parent TAF dosing observed in mouse and TFV-DP in mouse PBMC. IVIS imaging of rhodamine labeled homopolymer depots showed that degradation and release of the depot coincided with the sustained TAF release. Finally, these polymers showed excellent stability in accelerated stability studies over a six-month time period, and exceptional solubility of over 700 mg/mL in the DMSO formulation solvent. The homopolymer designs have a drug reservoir potential of well over a year at mg/day dosing and may not require cold chain storage for global health and developed world long-acting drug delivery applications. Unlabelled Image [ABSTRACT FROM AUTHOR]

A series of thermoresponsive diblockcopolymers of poly[2-(dimethylamino)ethylmethacrylate-block-di(ethyleneglycol) methyl ethermethacrylate], poly(DMAEMA-b-DEGMA), were synthesizedby reversible addition–fragmentation chain transfer (RAFT)polymerizations. The series consist of diblock and quasi diblock copolymers.Sequential monomer addition was used for the quasi diblock copolymersynthesis and the macro-chain transfer approach was utilized for theblock copolymer synthesis. The focus of this contribution is the controlledvariation of the ratios of DMAEMA to DEGMA in the copolymer composition,resulting in a systematic polymer library. One of the investigatedblock copolymer systems showed double lower critical solution temperature(LCST) behavior in water and was further investigated. The phase transitionsof this block copolymer were studied in aqueous solutions by turbidimetry,dynamic light scattering (DLS), variable temperature proton nuclearmagnetic resonance (1H NMR) spectroscopy, zeta potential,and cryo transmission electron microscopy (cryo-TEM). The block copolymerundergoes a two-step thermo-induced self-assembly, which results inthe formation of multilamellar vesicles after the first LCST temperatureand to unilamellar vesicles above the second LCST transition. An interplayof ionic interactions as well as the change of the corresponding volumefraction during the LCST transitions were identified as the drivingforce for the double responsive behavior. [ABSTRACT FROM AUTHOR]