Can activated carbon be used to adsorb and remove the monomers involved in emulsion polymerization?
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Polyacrylic acid emulsions have an irritating odor, likely due to incomplete reaction of the monomers. Can activated carbon adsorption be used to remove the residual monomers? Will this cause demulsification, or issues such as difficulty in separation and color change? Also, what is the smell of polyacrylic acid or polymethyl acrylate? Do they have an acidic taste?
No, that way the activated carbon won’t be filtered out, and demulsification may occur. The reduction of residual monomers (as mentioned above) can be achieved through the design of the initiation system, without the need for any other special treatments.
Reply to 2# mangnolia: I have referred to relevant literature; introducing a second initiator at the end of the polymerization process does not yield good results either
Can falling-film devolatilization, vacuuming, or nitrogen inflation be used to remove the residual monomer from the emulsion?
Reply to 4# rockey: What is falling film devolatilization? Is it stripping? Can it be done in the laboratory? It should be simple, without devices like stripping towers
Well, devolatilization refers to the removal of volatile components; it involves eliminating these volatile substances from the liquid phase by creating a larger vapor-liquid interface (usually small molecules and water that are produced during polymerization). This process is widely used in polymer production. http://bbs.sgst.cn/archiver/tid-6824.html Here, you can download the electronic version of \"Polymer Devolatilization\". The common types are falling film and strip type designs, which have relatively simple structures. http://www.sulzerchemtech.com/cn/desktopdefault.aspx/tabid-471/599_read-1179/ Here is a diagram of a devolatilization testing device manufactured by Sulzer; it’s a type of grid-slot falling-film devolatilization tower, CN1541742. This patent is also quite interesting – those interested can take a look
Both acrylic acid and methacrylic acid have an acetic-like acidic taste; after esterification, the resulting high-molecular-weight polymers have little to no taste at all. Acrylic and methacrylic monomers can easily cause skin allergies; generally, there are restrictions on such substances in foreign lotions, while it seems that no such requirements exist in China
Reply to 7# wssyx: The carboxyl groups on both my monomer and polymer have not been esterified. I’m not sure if you mean that pure polyacrylic acid or polymethacrylic acid has no odor. My goal is to get rid of the odor in the emulsion; it’s really unpleasant
The conversion rate in emulsion polymerization can’t be too high; there must be residual monomer
Reply 1# zongwei9456: It is generally removed by elimination afterward. It can also extend the insulation time, with the manhole left open during this process. http://blog.sina.com.cn/aqueous168materials