praseodym
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Styrene with kerosene? --> Polystyrene
I don't understand why kerosene is needed to polymerise styrene (phenylethene). Can someone pls 'enlighten' me on that?
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Quibbler
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I don't think it is. In fact the difficulty with styrene is stopping it polymerizing. Leave it in a bottle for a few months - it won't come
out again.
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solo
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Here is some infor on styrene's, which under high temp, polymerizing on it's own.........solo
Polystyrene and Styrene-copolymers
Applications, Synthesis and Kinetics
http://rapidshare.de/files/3477959/Polystyrene_and_Styrene-c...
It's better to die on your feet, than live on your knees....Emiliano Zapata.
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praseodym
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So is it true that the kerosene is TOTALLY unneeded??
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praseodym
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So it can't be an initiator for the reaction or a catalyst??
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daeron
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no way it is a initiator,my best guess is that it acts as a copolymer additive,sort of a Mw controll and maybe to help avoid the "gel
effect",yknow the self accleleration thingie(ohh i need a medal for the way i express myself,lol!).the mentioned synth is a stirene
polymerization in mass,right?if its a polymerisation in a solution than it acts as a solvent.
kerosene is a mixture not a pure compound and iso-alifatic and aromatic compounds dont act as initiators in any polymerization,at least i think so..
PS i havent read javas above posted links so this is maybe a doube post,or just a plain ol rant
[Edited on 30-7-2005 by daeron]
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praseodym
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By having kerosene as a copolymer, wont the end-product be a polymer made up of kerosene and styrene?? As in the product will not be polystyrene??
Furthermore, how can polymerisation lead to the gel effect??
And why is a solvent needed during polymerisation??
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daeron
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as i said i need to express myself more clearly-kerosene may act as a Mw control agent,to help avoid uncontrollable rxn rate increase,resulting in
-what do you call it the same thing happens during the vulcanisation of rubber-when chains bond via = bonds to form a net-like structure,and the
result is the "gel effect">extremly large Mw,extremly high viscosity,no liq state like quibbler said | Quote: | | fact the difficulty with styrene is stopping it polymerizing. Leave it in a bottle for a few months - it won't come out again
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a polimerization using solvents is often used when the monomer is soluble in the solvent and the polymer isnt or vice versa.if i remember correctly
polystyrene can be synth using polymerization in mass,solvent,emulsion,suspension...hmm did i miss one?
its so weird talking about chemistry not related to peas or tryps online...
anyways my guess its used as a solvent since its composition isnt constant,could you post the link to the procedure so we can clear it up? whats the
mech of the mentioned polymerization-free radical,kation,anion?
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praseodym
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This is the only puicture given to me (look at attachment). And i was asked what is the use of the kerosene.
Attachment: Styrene + kerosene.doc (24kB)
This file has been downloaded 804 times
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praseodym
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But i do agree on your point of view that the kerosene is mostly used as a Mw control agent or a solvent.
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praseodym
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Now i have added a new attachment which is clearer and more accurate and specific than the previous one.
The question goes like this:
In a polymerisation reaction, about 10cm3 of styrene and kerosene are mixed and refluxed for 45 to 60 mins using the set-up illustrated in the
attachment. The temperature will be about 150 degrees Celsius. After cooling, the reaction mixture is poured into about 5 times its own volume of
methanol. A waxy white solid was formed under the surface of the methanol. But my question would be what is the use of using kerosene and the
'methanol treatment'?
Attachment: StyreneKerosene.doc (26kB)
This file has been downloaded 766 times
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