Lots of interesting things in this week's C&EN:
- Big feature on the 100th anniversary of crystallography this week, including a fun editorial by Greg Petsko: "Clearly we are still a long way from the day when all structures of all molecules will simply be calculated from first principles. But if you seriously think that day will never come, I suggest you think again." This would make a great long bet, as to when that day would come.
- As a non-biologist, I learned a lot from this Matt Davenport article on the placenta.
- Another fine chemical M&A article by Rick Mullin, this one about phosgene manufacturers. Do you think that private equity firms owning chemical manufacturers is good or bad for their subsidiaries' chemical safety? I am skeptical, but reserve judgment.
- I didn't hear about this deadly explosion in Taiwan because of a propylene leak -- I wonder what happened there (other than leaking 10 tons of propylene, that is.) (article by Jean-François Tremblay)
Re phosgene: For a kilo-scale consumption, there are vendors selling a CO + Cl2 systems for on-site manufacturing. Gram scales phosgene generators usually crack triphosgene solid nowadays. We fall somewhere in between when we make our monomers on a hundred gram scale, so a kilo-scale phosgene generator is way too big for us, not mentioning the arrangements... Eventually we got fed up with hassle of buying phosgene 20% solution (increasingly difficult to transport) that we switched to diphosgene, even though is a far more costly and the yields aren't always as good as with phosgene. But the handling is much easier, and there is less metal contamination (from bottle cap corrosion). Triphosgene that is not cracked does not always work as a good replacement of phosgene if you need a clean reaction and a minimal workup with a sensitive monomer product.
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