I have 2 2 2-trifluoroethyl methacrylate polymer solution and I want to separate polymer from solvent , I used methanol but my polymer solution in methanol seemed cloudy . How can I precipitate polymer? which solvent is appropriate?
Dear friend Bahareh Kheilnezhad
Alright, here's the deal. When it comes to precipitating hydrophobic polymers, it's all about choosing the right solvent. Let me break it down for you Bahareh Kheilnezhad.
First off, using methanol might not be the best choice. Sure, it's a common solvent, but it doesn't always play nice with certain polymers, especially ones that are hydrophobic like 2 2 2-trifluoroethyl methacrylate. Hence, your Bahareh Kheilnezhad cloudy solution.
What you Bahareh Kheilnezhad need is a good non-solvent for your polymer. Something that can kick it out of solution without dissolving it. One of the go-to options is acetone. It's polar enough to mix with your methacrylate solution, but not so much that it'll dissolve the polymer. Plus, it evaporates quickly, which is always a plus.
So, here's what you Bahareh Kheilnezhad do:
1. Add acetone to your methacrylate solution gradually while stirring. You Bahareh Kheilnezhad want to find the sweet spot where the polymer starts to come out of solution, but you don't want to drown it in acetone.
2. Keep stirring for a bit to ensure everything's mixed nicely.
3. Then, let it sit for a while. The polymer should start to form a precipitate at the bottom of your container.
4. Once you see a good amount of precipitate, you Bahareh Kheilnezhad can either filter it out or simply decant the clear solution off the top.
And there you Bahareh Kheilnezhad have it. You've successfully precipitated your hydrophobic polymer. Give acetone a shot, and I think you'll see much clearer results.
Dear all, you forgot to mention the solvent in which the polymer is soluble! This is crucial in choosing the best non-solvent. Other important remark that is not considered by many researchers in doing precipitation. There are two possibilities, either to add the solution to the non-solvent or to add the non-solvent to the solution. The first one is the correct way that is not unfortunately followed by many researchers. When you add the non-solvent to the solution, long chains are more sensitive to its presence, they contract first, followed by the shortest chains. This is a chromatographing or a fractionation phenomenon. At the end, the resulted mass is a gradual decrease of MW from the core to the outer surface. I noticed this with polyacrylamide. Samples from the surface have different features compared to those taken from the core, mainly MW.
For the second procedure, pouring the solution into the non-solvent resulted in homogeneous mass since long and short chain are following simultaneously into the non-solvent, so they precipitate together, resulting in a uniform mass. My Regards
Kaushik Shandilya Thanks for your reply. my molecules weight is high enough to precipitated. I did what you exactly suggested to me and it did not work and solution was not cloudy and this time was so clear!
Finally, I discovered the solution and am sharing the procedure below: the reactant sample was poured into an excess mixture of methanol and water (7:3 w/w) to precipitate.
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