I encounter two questions during SI-ATRP. My experiment route is shown as follows.
First ATRP reaction, MSN-Br(100mg), GMA( Glycidyl methacrylate, 1.5mmol), PDMETA(Pentamethyldiethylenetriamine,0.1mmol),DMF(2 mL) mixed togather and degassed by three vacuum/nitrogen cycles. Then add CuBr(I) 0.05 mmol into mixture, degassed again. The polymerization was performed for 5 min at the room tempurature. This step can gain MSN-PGMA. After cleaved from MSN by HF, obtained PGMA can't dissolve in any solvent.Why??
First ATRP reaction, MSN-PGMA(100 mg), DMAEA(Dimethylaminoethyl acrylate, 5mmol),PDMETA(Pentamethyldiethylenetriamine,0.1mmol), Methanol(5mL) mixed together and degassed by three vacuum/nitrogen cycles. Then add CuBr(I) 0.05 mmol into mixture, degassed again. The polymerization was performed for 7 h at the room tempurature. This step can failed. The PDMAEA isn't grafted. Why??
try this paper
Bulk transparent epoxy nanocomposites filled with poly(glycidyl methacrylate)
brush-grafted TiO2 nanoparticles
Peng Tao
and we used raft to graft sio2, Tio2, and Zr Nps
For the reaction of grafting polymer to silica surface, you need to on the surface were able reactionary groups such as vinyl, acrylic, styryl and so on.
MSN-Br you mean ATRP initiator grafted Silica? If yes, see in that case you have sufficient initiator grafted on silica surface which can assist to graft (/hold) considerable number of chains on particles. I think in your case instead of surface initiated polymerization the cross-linking (both acrylate and ring opening of epoxide) may be giving you the insoluble polymer. OR it is also possible that during detachment HF mediated ring opening is leading to cross-linking which leads to insoluble polymer (less sure about this one but look for some ref.)
In the second case where you have PEGMA functionalized Si you can simply carry out free radical polymerization than ATRP it can also guarantee good polymer grafting.
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