[JSUCY232]

I synthesized a polymer, which is 80% methyl methacrylate and 20% tetrachloroethylene. I ran IR on it, but am having trouble characterizing the peaks, which would primary be C-Cl peaks in the region of 650-900. I have an IR with starting materials and products (labelled) and an IR of tetrachloroethylene and hexachloroethane for reference. In this reference spectrum. I observe 2 peaks, and shifts from 902-774 cm-1 and 761 to 673, which are in the SP3 vs SP2 C-Cl bonds. I also have peaks in those regions for the TCE vs polymer, but there are overlapping peaks in the starting material, since this is the fingerprint region. I am therefore having trouble characterizing the peaks. I am trying to provide support for polymerization via IR for publication. I also have DSC data. I definitely have a polymer. I prefer not to use NMR, since IR would be simpler, but I have it available, if necessary. Anyone care to take a stab at it? I can do NMR, if necessary, but the goal of this small project is just to confirm polymerization for preliminary data for another project.

[JSUCY232]

I had trouble with the attachments. Hopefully, they are working now.

[mjc123]

Your best bet for confirming polymerisation (other than the thing being a solid, I suppose) would be the disappearance of the C=C band of MMA at ca. 1600 cm^-1 and the vinyl C-H at 3100. Unfortunately this would only confirm polymerisation of MMA, not incorporation of TCE, as TCE has no vinyl C-H and no C=C band (due to symmetry). I suppose if you wash it thoroughly to get rid of any unreacted TCE, and TCE-like bands are still there, that would help.

I would not use HCE as a model for the polymer. (Better 2,2,3,3-tetrachlorobutane, if you can get it?) The C-Cl bands don't shift very much between vinylidene chloride and PVDC. Perhaps this reference might help you (I can't access the full text): https://pubs.acs.org/doi/pdf/10.1021/ba-1973-0128.ch010 Copolymerisation of TCE and ethylene. Note the maximum mole fraction of TCE they can get in the polymer is 14% - you will need good evidence to support a claim of 20%. How about the NMR?

[wildfyr]

NMR is the simplest method, this would not be a hard to characterize.

If you just want to confirm it's a polymer, use GPC, it will tell you moelcuslr weight. Some astute NMR can tell you the ratio of monomer incporation.

If it's a solid you kind of have you answer anyways. Both of these monomers are liquids.

[JSUCY232]

Thanks for your suggestions. I will look into them. I agree that I need to run NMR. MJC123, We did 20% by volume, but our hardest polymer was at 10% TCE by volume, so that might explain the difference in hardness. I did not calculate mole fraction. Don't know why I didn't do that. Thanks again.

[wildfyr]

Look up the concept of monomer reactivity ratio and the Mayo-Lewis equation. These concepts describe the relative reactivities of monomers, i.e. their likelihood of being incorporated into a growing free radically polymerizing chain. Its not a simple concept but it is important for what you are doing, especially if you wish to publish this data.

[JSUCY232]

I will do that. Thank you.