Studies on the Free Radical Polymerization of N-Vinylpyrrolidinone in 3-Methylbutan-2-one

Abstract

N-vinylpyrrolidinone was polymerized in 3-methylbutan-2-one, which acted as both solvent and transfer agent. The main products of this reaction were poly(N-vinylpyrrolidinone)s with methyl ketone chain ends. These polymers were formed by transfer to solvent involving abstraction of hydrogen at either the isopropyl or 1-methyl position. MALDI-TOF mass spectrometry was used to fully characterize the polymers, and several other initiation and termination events were found to occur. Thus end groups associated with initiation by and combination with the primary radical were observed. Isopropyl end groups were formed as a result of fragmentation of 3-methylbutan-2-on-1-yl radical produced as a consequence of transfer to the 1-methyl group of 3-methylbutan-2-one. This fragmentation also yielded ketene, which underwent initial propagation followed by rapid extraction of a hydrogen atom from 3-methylbutan-2-one and yields aldehyde end groups that were observed in both NMR and MALDI-TOF spectra. Also, end groups associated with termination by combination between propagating and solvent radicals were observed.

New Stimuli Responsive Poly(1‐vinylpyrrolidin‐2‐one) Bearing Pendant Activated Disulfide Groups

“…P(VP-co-VP-COOH) was obtained (Scheme 1) by simultaneous saponification and decarboxylation of a copolymer of VP with 3,3-di-(ethoxycarbonyl)-1-vinylpyrrolidin-2-one (DEVP) obtained in the presence of methyl isobutyrate (MIB) as a chain transfer agent, according to a method previously established in our laboratory. [13][14][15][16] DEVP, in turn, was prepared by treating the VP anion obtained by reacting VP with lithium diisopropylamide with ethyl chloroformate. [17] Subsequently, the active disulfide containing PVP, P(VPco-VP-SS-Py), was prepared following the four step pathway depicted in Scheme 2.…”

“…[12] In this regard, our group has previously reported on PVP oligomers functionalised at one chain end with reactive functions, prepared by the radical polymerisation of 1-vinylpyrrolidin-2-one (VP) in the presence of functional chain transfer agents. [13][14][15][16] Recently, we have also reported the synthesis and polymerisation of 3,3-di-(ethoxycarbonyl)-1-vinylpyrrolidin-2-one (DEVP). By simultaneous saponification and partial decarboxylation, the DEVP units lead to carboxylated VP units.…”

The use of radical polymerization in the synthesis of telechelic oligomers

“…We and others have used these features to prepare a wide range of monotelechelic oligoNVPs [58][59][60][61]. We have also successfully used transfer to solvent to produce vinyl acetate oligomers with alcohol end groups [62].…”

Synthesis and Characterization of Thermo-responsive Poly(N-vinyl-2-pyrrolidinone)-block-poly(N-isopropylacrylamide) Micelles

“…As a typical example of "smart" polymers, due to the exhibition of the well-known LCST in water, the selfassembling of PNIPAM-based block polymers has been Downloaded by [Eindhoven Technical University] at 09:53 19 October 2014 widely used in the field of different applications like environmentally responsive micelles, drug delivery, smart surfaces (9), catalysis (10), temperature-controlled carrier for reaction of biomacromolecules and so on. The volume phase transition temperature of PNIPAM can be adjusted when it copolymerizes with hydrophilic or hydrophobic monomers such as poly(ethylene glycol) (PEG) (11,12), poly(methyl methacrylate) (PMMA) (13,14), poly(N, Ndimethylacrylamide) (PDMAAM) (15), and polystyrene (PS) (16).…”