Efficient synthesis of a polyacene monomer (Technion)
Polyacenes are actually a chain of benzene rings (see figure). It is widely believed that polyacenes would have unprecedented properties: non-linear optics, substantial mechanical strength (similar to Kevlar™) and high directional (anisotropic) conductivity; i.e. conductive in one dimension/direction – insulator in others; this means, for example, that two conducting wires may cross each other without a separating insulator. According to estimates the conductivity will be so high it would be considered high temperature superconductivity (above 77K). There is also a possibility that this polymer will be room-temperature (RT) superconductor, based on a theoretical assumption that organic polymers have a large potential of being RT superconductors1.
These polymers are currently unknown because there is no efficient way of their production. So far the longest chain that has been prepared consists of 7 monomers. We believe that the key to preparing a true polyacene (with 10 benzene rings and more) lies with a high-yield method to prepare a specific monomer. The currently known method has a yield of 2%.Method:
Our method addresses the low yield problem. The method is based on two main changes: A) Since the monomer decomposes under the same conditions required to prepare it, we remove it from the reaction’s solution as soon as it is created; B) Enlarging the surface area of the catalyst.
As the electronic properties develop upon adding monomers, it is realized that unprecedented properties will exist if the length is extended beyond 10 or more monomers, for example, high directional conductivity, high mechanical strength, and possibly superconducting properties.
Our method presents what is believed to be a key step towards the preparation of polyacenes. Our method has a 36% yield vs. 2% in current methods (for said monomer).
• High directional conductivity (anisotropy) – ability to place wire upon wire without insulation
whatsoever; allows crossing of wires without isolation at all
• Great mechanical strength - similar to Kevlar™
• Possible high temperature or maybe room-temperature superconductive properties
Judging by the electronic properties which develop upon monomer adding to the polyacene, the polymer is predicted to have unprecedented conductive properties if extended beyond 10 units.
• Anisotropy of the polyacene may lead to revolution in many fields, including VLSI, electronics and the way we use electricity overall.
• High temperature superconductivity is primarily harnessed to produce very powerful magnetic fields for various applications, e.g. MRI/NMR, RF and microwave filters.
• RT superconductivity may revolutionize the way we use electricity. It may enable long distance energy transfer and save a large portion of the energy wasted on long distance transmission (currently 7-8%). In addition, reduced wire resistance can assist speeding up ULSI/VLSI circuits and save some power.
CHM-0599
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