In recent, the many environmental concerns associated with plastic’s constituents have led to the search for sustainable high-performance thermoplastics that are entirely or partially derived from bio-derived feedstocks, instead of petrochemicals, and match those that they replace in terms of thermomechanical properties 1. Poly(arylene ether)s (PAEs) are a major group of SEPs, and they include polysulphone (PSU), polyether ether ketone, and polyphenylsulfone 12, 13. SEPs, also known as high-performance or specialty thermoplastics, are gradually replacing thermosets and pseudo-thermoplastics as thermally and mechanically robust materials for aircrafts, automobiles, electronics, dental devices and in household/children’s products because of their recyclability 2, 11. Likewise, substituting thermosets with thermoplastics for many other applications increases the recycling rate of plastic wastes.Īccording to superiority of thermal and mechanical performances, thermoplastics are generally classified in the following order: commodity plastics 150 ☌ 1, 7, 8, 9, 10. If electronic parts are made of thermally durable thermoplastics, both plastics and metals from PCB can be effectively recycled by melting or dissolution 6. After curing, thermosets and pseudo-thermoplastics do not melt and dissolve the separation of metal from PCB requires harsh chemical degradation or pyrolysis of plastics, and the recycling of plastics is difficult 4, 5. polyimide, generally have higher thermal stability thus, they are more preferred to thermoplastics as materials for PCB 4, 5. The typical content of metals, plastics, and ceramics in PCBs is ~40, 30, and 30 wt%, respectively 2, 3. For example, abandoned electronics notably create printed circuit board (PCB) waste.
The colossal demand for plastics has led to a large amount of wastes. Since plastics have become indispensable in our life, their consumption has exponentially increased 1. Interestingly, quantum chemical simulations show the alicyclic bicyclic ring structure of isosorbide imposes stronger geometric restraint to polymer chain than the aromatic group of bisphenol-A. Such a performance combination has not been reported before for bio-based thermoplastics, petrochemical SEPs, or thermosets.
It is transparent and solvent/melt-processible for recycling, with a glass transition temperature of 212 ☌, a tensile strength of 78 MPa, and a thermal expansion coefficient of 23.8 ppm K −1. Here we use a phase transfer catalyst to synthesise an isosorbide-based polymer with a high molecular weight >100 kg mol −1, which is reproducible at a 1-kg-scale production. However, previously reported bio-derived thermosets or thermoplastics rarely offer thermal/mechanical properties, scalability, or recycling that match those of petrochemical SEPs.
isosorbide instead of restricted petrochemicals. Camera manufacturerĪdobe Photoshop Lightroom Classic 10.Environmental and health concerns force the search for sustainable super engineering plastics (SEPs) that utilise bio-derived cyclic monomers, e.g. The timestamp is only as accurate as the clock in the camera, and it may be completely wrong. If the file has been modified from its original state, some details such as the timestamp may not fully reflect those of the original file.
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