I've personally begun looking at routes and asking: does it pass the one-armed man test?:
It does, for example, no good to offer an elegant, difficult and expensive process to an industrial manufacturing chemist, whose ideal is something to be carried out in a disused bathtub by a one-armed man who cannot read, the product being collected continuously through the drain hole in 100% purity and yield. - Sir John Cornforth, Chemistry in Britain, 1975, 432.Hardly anything does, but it's an ideal to keep in mind. Happy Wednesday!
That's a decent description of reactive extrusion: dump in the ingredients (continuously)and out comes your polymer (continuously). We make a lot of money doing that.
ReplyDeleteHey, John -- when that polymer comes out, what form does it take? i.e. what's the shape of the material after it's been extruded? Sheets? pellets?
ReplyDeleteIt depends on a lot of factors. A die can shape it into various profiles or stands that can be chopped into pellet. Adhesives come out as a large diameter and typically fill 55 gal. drums. I've not seen sheets done as part of reactive extrusion, but I could be I suppose.
ReplyDeleteDangers of reactive polymers: I worked briefly in the analytical lab at an epoxy plant. Among the weeds in the back lot there was a 20,000 L reactor with all the connections hacked off. Asked the boss what was up with it: "Well, son, that's what happens when you polymerize a batch."
ReplyDeleteeka-germanium: this is very funny, I have heard of couple screw-ups done on a plant scale and they all led to epic stories.
ReplyDeleteHarrison Ford is "The Chemist"
ReplyDelete'No sir, I didn't do it. It was the one-armed man!'
Another nice quote (I hope I repeat it correctly): You know that you have designed a robust process when no plant operator calls you in the middle of the night
ReplyDelete