Summary: Oriented poly(ethylene-2,6-naphthalate) (PEN) has been characterised by polarised FT-IR spectroscopy to determine the structural angles of the transition moments to the molecular chain axis. The bands at 1130 cm À1 , 1142 cm À1 and 1602 cm À1 , which have been previously assigned as having their transition dipole moments parallel to the chain axis, are confirmed as parallel bands. Bands at 767 cm À1 and 831 cm À1 are confirmed as perpendicular bands. However the band at 1708 cm À1 which has previously been assigned as a perpendicular band, is shown here to have its transition moment at 728 to the molecular axis.
Metal-organic framework (MOF) compounds have the largest surface area of any materials known. Just 1 g of some MOFs can offer a surface area in excess of 2 km2. These huge surfaces are potentially useful when gases and liquids need to be captured, stored, or separated. And chemists can design them to be selective about which molecules they absorb. Given the extraordinary properties they exhibit, it’s no wonder that industrial scientists are intrigued by these crystalline, porous materials. About a decade ago, a wave of chemical and other companies embarked on major projects to develop MOFs, which consist of metal ions or clusters and organic linkers arranged into nanoscale structures. They were after MOFs that could store hydrogen or natural gas at relatively low pressures to power vehicles. They soon realized, however, that the market for such cars was a distant reality and that MOFs were too expensive even if
AkzoNobel and Renmatix, a specialist in making materials from biomass, have formed a partnership to make biobased additives for paints and construction materials. Renmatix’s Plantrose process uses supercritical water under high temperature and pressure to break down biomass. The partners will explore applications for a crystalline cellulose isolated with the process. Renmatix was a 2017 winner of AkzoNobel’s Imagine Chemistry start-up contest.
It was 2007. Apple CEO Steve Jobs announced the iPhone, J. K. Rowling finished her seventh and final Harry Potter novel, and the worst financial crisis since the 1930s was about to hit. It was also the year that Gene Berdichevsky, an engineer and employee number 7 at Tesla, the electric car pioneer, began questioning why gains in recent years in the energy density of lithium-ion batteries had fallen from 7–8% to 3–4%. With returns from improvements in battery cathode performance beginning to taper, Berdichevsky began to consider the next bottleneck—the poor energy density of the traditional graphite anode. Tens of start-ups and established materials firms eventually began asking the same question. Many came to the same conclusion as Berdichevsky: that silicon or lithium would be ideal as an anode material. In theory, they are able to hold roughly 10 times the number of electrons as graphite, leading to lithium-ion
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