What is the normal industrial process for making HTPB ( hydroxy terminated polybutadiene)? ie is it emulsion, solution etc. Reaction conditions , temperature etc. glass lined reactors? is it made in continous reactors or batch? Just curious if it could be made easily in an existing emulsion SBR or Zeigler Natta Polybutadiene plant.
Any information in Kirk-Othmer or Ullmann's? Whatever is available there would be public knowledge written by people with experience. You can also try the patent literature, although that is far less reliable as to what is real and what is not. (Read a few patents in the area that you are knowledgeable about and you will see what I mean
- and the recent KSR decision here in the US will only make it worse - bogus patents are certainly unobvious since they are so bogus, right?)
Otherwise I fear that you may run into the wall of corporate secrecy. HTPB is a value-add over PB (a commodity) so the profit there will be jealously protected.John Aspen Research, -
Opinions expressed herein are my own and may not represent those of my employer.
Patent literature is an obvious place to go but I disagree that it is unreliable in that a well written, valid patent will normally have a good first working example. I like to be helpful but sense a laziness in the OP's request and if he is a student or getting paid to do the work, he should put in the sweat equity.
Frank
I am neither a student nor getting paid to find out how to make HTPB, nor am I lazy. Nor do I have any intention of making HTPB I am just curious as I also have a strong interest in space flight , where I know HTPB is used as a solid rocket propellant. I cant justify my employers time or my own money researching something out of pure curiostiy. Patent literature does not necessarily tell you how things are done in practice, which is what I really wanted to know. If you ever read any of my posts on usenet you will see that I will always go out of my way to help others where I can. I dont make assumptions about people that I have no way of veryfying. I can understand people who want to hold on to knowledge to protect proprietery information etc but I'll never understand the mentality of people who simply dont want to share knowledge because they dont want to make it easy for someone else. But if you choose to do otherwise good luck to you, and if you ever want to know anything about making emuslion SBR or solution PB feel free to call on me. I worked in a plant that is now closed so I have no secrets to protect and the only use for all that knowledge now is to share it with others. ( I would have to migrate to another country to continue in the field which I am not prepared to do) terry
Kinda nitpicking, but I did say "less reliable", not "unreliable".
The problems I see in reading patent literature:
1) It is not peer reviewed. Not that peer reviewing is free from its own problems, but I've read too many patents a)filled with mindless drivel of what the inventors think is going on, and/or b) with no supporting data, and/or c) too vague to be able to easily repoduce ther results in the lab. While patent examiners do have technical degrees, most do not have enough industrial experience to qualify as a PHOSITA (person having ordinary skill in the art). 2) There is no incentive to produce a "well written" patent, as it further limits the potential broadness of the claims. Using "weasel words" helps to broad the claims after the patent is issued. 3) Patents are often written early in the R & D cycle before the true optimum has been developed. Hence the "best example" is only the "best example" at the time of application. 4) Patents that are complete b***s*** are easy to get because PHOSITAs aren't patenting in that area because it is such b***s***. Just this week I ran across a patent where you can tell the inventors either 1) did not have a engineering degree because they had such a lousy understanding of force vectors or 2) should have there degrees withdrawn because of the same issues. Now I have to explain to our client why they don't have to worry about this newly issued patent AND why we can't try and "get around their patent" with a new product that does what the patent claims can be done.Being able to separate the wheat from the chafe is a real skill that can be difficult without experience, and even thought, you can still get snowed.
Certainly a number of the questions posed by the OP could be answered by patents (emulsion vs. suspension, temperature ranges, continuous/ batch), but the glass-lined reactor question and the upgraded ZN questions most likely can't be.
John Aspen Research, -
Opinions expressed herein are my own and may not represent those of my employer.
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