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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: rjb on June 24, 2022, 12:14:13 PM

Title: p-divinylbenzene
Post by: rjb on June 24, 2022, 12:14:13 PM

Hi,

Having just looked up the price of p-divinylbenzene I nearly had a heart attack!
Without really giving too much thought on why it was so expensive, I pondered whether purification of Technical grade divinylbenzene (mixture of m, p isomers, ethylvinylbenzene and diethylbenzene) was a possible option.

Having now gathered that separation is damned difficult (hence presumably the price for p-DVB being so high), I wondered if any of you had any experience in this at all and could suggest any kind of separation that is remotely feasible? If it not something that is feasible, then I guess I shall either abandon my intended application or give it a go with a technical grade mixture and see what happens!

Many thanks

R 

Title: Re: p-divinylbenzene
Post by: rolnor on June 25, 2022, 05:32:35 AM

I think you can find a vendor with reasonable price, its common in polymer manufacturing.
Here is a list if you scroll down:

https://pubchem.ncbi.nlm.nih.gov/compound/1_4-Divinylbenzene

Title: Re: p-divinylbenzene
Post by: rjb on June 27, 2022, 05:20:37 PM

Thanks Rolnor,

I shall give it a go, I have nothing to lose by trying... The prices for the big vendors in the UK (the only ones who seem to stock) are pretty steep...

Sigma Aldrich = £758 ($929) for 5g @ 85% purity
VWR - £1090 ($1336) for 5g @ unstated purity!

Kind Regards

R

Title: Re: p-divinylbenzene
Post by: wildfyr on June 27, 2022, 08:28:28 PM

Rolnor, I think the isomer mishmash is whats used in manufacturing.

OP look in the patent literature, I bet some weird distillation and/or freezing is used to purify, but I bet its complicated.

Title: Re: p-divinylbenzene
Post by: rolnor on June 28, 2022, 04:29:51 PM

Yes, maybe, but I think you can find better deal than Aldrich. Its also easy to synthesize

Title: Re: p-divinylbenzene
Post by: wildfyr on July 02, 2022, 12:23:15 PM

Vwr is typically one of the cheapest fine chemical supplier.

How would you make it? Any retrosyntheais involving FC of benzene is going to have a mishmash. What comes to mind is diformylation followed by wittig but seems like that gives meta. I bet m divinyl benzene is most common isomer

Title: Re: p-divinylbenzene
Post by: rjb on July 04, 2022, 09:53:52 AM

Quote from: wildfyr on July 02, 2022, 12:23:15 PM

How would you make it? Any retrosyntheais involving FC of benzene is going to have a mishmash. What comes to mind is diformylation followed by wittig but seems like that gives meta. I bet m divinyl benzene is most common isomer

Many thanks for the replies on this. It seems that the m:p isomer ratio is about 3:1... the o isomers tend to form napthalene during the synthesis process so aren't present in most grades of DVB.