I want to make poly(norbornene 2-carboxylic acid), for the sake of characterization, I decided to start with the protected monomer norbornene-tert-butyl-2-carboxylate for the ring-opening metathesis polymerization (ROMP). In the deprotection step (with TFA/DCM), I expected to see the deprotected polymer precipitating out, however, I could not see any undissolved substances in the reaction mixture. I evaporated and precipitated the polymer in hexane and checked NMR and FTIR from which I realised that the tert-butyl groups have been converted to carboxylic acid groups. But I wonder how it could be still soluble in DCM.
Does anybody have a similar experience? If so, please share your experience here.
Thank you in advance.
Dear all, I think it is due to the low MW of the ROMP polymer (compared to the addition one), may be the product is only oligomers. What is the MW? My Regards
Dear all, I think it is due to the low MW of the ROMP polymer (compared to the addition one), may be the product is only oligomers. What is the MW? My Regards
But the MW is above 100 kDa Abdelkader BOUAZIZ
I used to make poly(t-butyl acrylate) copolymers by free-radical and RAFT process (mw=20-100 kDa), and I could successfully carry out the deprotection with TFA/DCM. But when it comes to the ROMP polymers (for both homopolymer and copolymer), it is soluble in the DCM before and after deprotection.
But I wonder how it could be soluble in DCM in the protonated form (I believe DCM cannot form H-bonds)
Could you send me any supporting papers James E Hanson
- Badges
- Science topic