[biostech]

Hi everyone,

I'd like to functionalize the surface of a commercial polystyrene petri dish in order to have hydroxyl groups or even better acrylic or metacrylic ones.
Anyone knows a method/protocol? The simplest and cheapest as possible of course.

(I've tried: air plasma + silanes, UV ozone)
thanks in advance,
steve

[fledarmus]

Do you know what the structure of polystyrene is? What functional groups do you have to work with?

[biostech]

Do you know what the structure of polystyrene is? What functional groups do you have to work with?

It's a commercial one. I don't know if is cis or trans but the monomere is standard benzene on alifatic chain.
http://en.wikipedia.org/w/index.php?title=File:Polystyrene.svg&page=1

[fledarmus]

Right - once the monomer is reacted, all you have is a long alkane chain with pendant benzene rings. To have any chance of reacting with the polymer, you need a reaction that occurs on a weakly substituted (alkyl) benzene ring, on the activated α-carbon, or on the alkane chain. There aren't many clean possibilities. You could look at electrophilic aromatic substitution reactions - you probably don't need to react every single benzene ring so even low yield reactions, if they are clean, should be effective.

Usually if you really need particular functional groups in a polymer, it is easier to incorporate them into the monomer before the polymerization reaction. If you're trying to use commercial products, that's probably not available.

For commercial products, of course, you will also have to worry about contamination from plasticizers and co-monomers the manufacturer uses to adjust the properties of the polymer. It's hard to tell what those are without specific information from the manufacturer.

[biostech]

yes, i just need a roughtly modification of PS. I have to covalently attach a polyacrylamide which is polymerizing. Since this gelification is performed through a radical reaction is there no way to use the radicals to attack the PS surface too?
Benzophenone?

many thanks

[fledarmus]

Benzylic positions are subject to radical attack - you might try something along these lines:

http://pubs.rsc.org/en/Content/ArticleLanding/2011/OB/c0ob01148g

Just remember, this is also a very sterically hindered position, especially when your styrene chains are packed together into a solid.

[miketout]

yes, i just need a roughtly modification of PS. I have to covalently attach a polyacrylamide which is polymerizing. Since this gelification is performed through a radical reaction is there no way to use the radicals to attack the PS surface too?
Benzophenone?

If you are radically polymerizing acrylamide either in a solvent, which is at least a fair PS solvent, or in bulk and acrylamide somewhat solvates the polystyrene, it seems very likely that you get some amount of radically initiated cross links with the PS benzenes.

[biostech]

Dear all,

plastic polystyrene dished are a common equipment in various labs.
I am trying to functionalize the inner surface in order to expose chemical groups that are good for any further functionalization step. Ideally, I would like acrylate or vynil groups on the surface.
Important: I want to maintain the optical clarity of the dish, additionaly all reation must be <70 ºC to avoid plastic melting.
Someone told me that azides may be a good option to react towards the phenyls of polystyrene..
Which is your suggestion?

Best

[Arkcon]

Hi there, biostech:, I've gone and merged your recent question with a similar question of yours.  I hope you can build on what you know, to keep solving your problem.

[wildfyr]

Hey, my area of expertise!

You can certainly use azides or benzophenone containing molecules and UV cure them to the surface. A good chunk of my PhD was on sulfonyl nitrene insertion on tough-to-functionalize surfaces. How much synthesis do you feel like attempting? I can think of several good pathways to using either of these moieties, but all of them are going to require some degree of small molecule/polymer synthesis.

I'm guessing you want to do some grafting-through polymerization on the polystyrene?

Just a note: Unless you are trying to access the triplet nitrene (usually thermally at >100C), the alkyl backbone is going to be the target for these photo-initiated functionalization reactions.