Phase-separated and self-assembled co-network materials offer a simple route to bicontinuous morphologies, which are expected to be highly beneficial for applications such as ion, charge, and oxygen transport. Despite these potential advantages, the programmed creation of co-network structures has not been achieved, largely due to the lack of well-controlled chemistries for their preparation. Here, a thiol-ene end-linking platform enables the systematic investigation of phase-separated poly(ethylene glycol) (PEG) and polystyrene (PS) networks in terms of the molecular weight and relative volume fractions of precursor polymers. The ion conductivity and storage modulus of these materials serve as probes to demonstrate that both phases percolate over a wide range of compositions, spanning PEG volume fractions from ∼0.3-0.65. Small angle X-ray scattering (SAXS) shows that microphase separation of these co-networks yields disordered structures with d-spacings that follow d∼Mn0.5, for 4.8 kg/mol

Dietary Si, as soluble orthosilicic acid (OSA), may be important for the growth and development of bone and connective tissue. Beer appears to be a major contributor to Si intake, although the Si content of beer and its bioavailability in human subjects have not been well established. Here we investigated the Si content of different beers and then estimated Si absorption from beer in healthy volunteers. The Si content of seventy-six different beers was estimated using inductively coupled plasma optical emission spectrometry and one of the beers, used in the ingestion study, was ultrafiltered to determine OSA content. Next, following the ingestion of 0·6 litres beer (22·5 mg Si; 4·6 % (v/v) ethanol), serum and urinary Si levels were measured in nine healthy volunteers over a 6 h period. A solution of OSA was similarly investigated as a positive control and water and 4·6 % ethanol as negative controls. The mean Si level of beer was 19·2 (SD 6·6) mg/l; the median Si level was 18·0 mg/l. There was no significant difference in the Si levels of the different beers by geographical origin or type of beer. Serum and urinary Si levels increased considerably following the ingestion of beer or a solution of OSA but not with the ingestion of either 4·6 % ethanol or water. The ultrafilterability of Si from beer (about 80 %) and its absorption in volunteers (about 55 %) was comparable with that of a solution of OSA suggesting that Si in beer is present chiefly in a monomeric form and is readily bioavailable.

End-functionalized poly(ethylene glycol) (PEG) and polydimethylsiloxane (PDMS) were cross-linked by a thiolene reaction with a tetra-functional thiol to create robust, tunable networks. These networks were loaded with increasing amounts of lithium bis(trifluoromethane sulfonyl imide) (LiTFSI), and their ion conductivity was measured. A wide range of salt loading was achieved, allowing the investigation of both salt-in-polymer and polymer-in-salt regimes. Thermal, mechanical, and ion conductivity properties of LiTFSI-loaded PEG and PEG-PDMS networks were measured. Even at high salt loadings, both networks maintained rubber-like characteristics, which were stable over a range of temperatures (30−90°C). The PEG network with the highest salt loading showed the greatest ion conductivity, 6.7 × 10 −4 S cm −1 at 30°C, as measured by impedance spectroscopy. This system provides a route to optimize lithium ion conduction and mechanical properties.A ccess to affordable, clean energy is a well-recognized scientific and technical challenge of this century.

Multiblock copolymers, composed of different combinations and number of blocks, offer appreciable opportunities for new advanced materials. However, exploring this parameter space using traditional block copolymer synthetic techniques, such as living polymerization of sequential blocks, is time-consuming and requires stringent conditions. Using thiol addition across norbornene chemistry, we demonstrate a simple synthetic approach to multiblock copolymers that produces either random or alternating architectures, depending on the choice of reactants. Past reports have highlighted the challenges associated with using thiol−ene chemistry for polymer−polymer conjugation; however, using norbornene as the "ene" yielded multiblock copolymers at least four or five blocks. Preparation of new multiblock copolymers containing two or three block chemistries highlights the versatility of this new approach. These materials were thermally stable and showed microphase separation according to characterization by DSC, SAXS, and AFM. This chemical platform offers a facile and efficient route to exploring the many possibilities of multiblock copolymers.

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