Polyvinylamine - a base for new routes in hydrophilic polymers development
Polimery 2005, No 7-8, 491
A review of a many-year-long research on the method of preparation of polyvinylamine (PVAm) precursor suitable for implementation into industry has been presented. Just a few years ago BASF introduced the production of poly(N-vinylformamide) (PNVF) from easily polymerizing N-vinylformamide (NVF). PNVF hydrolysis in mild conditions leads to PVAm [equation (4)], which is now available on the market as well as NVF, and PNVF. The results of own research concerning NVF structure investigation were discussed. 13C NMR investigations let explain the higher reactivity of this monomer than of isomeric acrylamide. It was also found that PNVF hydrolysis in both acidic or basic environment was accompanied with ammonia evolution, not described up to now in the literature, what resulted in formation of some amount of g-lactam units in PVAm [equation (5)]. The presence of NH2 groups in PVAm, bonded with backbone, creates various possibilities of their functionalization (Scheme A). Low solubility of PVAm in organic solvents is really a disadvantage but carrying out the polyreactions and then modification reactions in microemulsions let overcome it. Polymerization of methacrylamide in microemulsion with subsequent crosslinking with glutaric aldehyde [reaction (6), Fig. 5 and 6] is given as an example of this manner. NVF polymerization in microemulsion is a subject of another paper of the authors.
Key words: N-vinylformamide, poly(N-vinylformamide), hydrolysis, polyvinylamine, functionalization of amine groups, microemulsions