NMR Spectroscopy and MALDI‐TOF MS Characterisation of End‐Functionalised PVP Oligomers Prepared with Different Esters as Chain Transfer Agents

Abstract

Ester-functionalised poly(1-vinylpyrrolidin-2-one) (PVP) oligomers obtained by radical polymerisation in methyl propionate, diethyl malonate and diethyl 2-methylmalonate were characterised by NMR spectroscopy, and MALDI-TOF mass spectrometry. The chain-transfer constants were determined as 5.54 x 10(-4), 1.22 x 10(-3) and 1.70 x 10(-2), respectively, by measuring the variation of the number-average molecular weight on conversion. These values were compared with those of methyl isobutyrate (1.65 x 10(-3)) and ethyl lactate (1.03 x 10(-2)), which had been previously determined. A clear dependence was found on the reactivity of the mobile hydrogen atoms alpha with the ester group. All of the macromolecules carried a single ester function. Therefore, the re-initiation step by the CTA-derived radicals overwhelmingly prevailed over initiation by the primary radicals.

One-step synthesis of poly(lactic-co-glycolic acid)-g-poly-1-vinylpyrrolidin-2-one copolymers

“…30 The grafting degree, that is, the average number of PVP side chains per PLGA main chain of PLGA-g-PVP MP samples (calculated from the number average molecular weight of the PLGA main chain, the number average of the PVP pendants and the PLGA/PVP w/w ratio) were 1.5, 1.1, and 1.0. The grafting degree was proportional to the [T]/[M] ratio, therefore decreased by increasing the NVP content in the feed.…”

“…The chain transfer involved one hydrogen atom a to the ester function. [23][24][25][26][27][28][29][30] Compared with ATRP or RAFT, this synthetic method gave end-functionalized oligomers with broader molecular weight distribution, but had the merit of being very simple and easily scaled-up.…”

Anwendung von Poly(ethylenglycol) beim Wirkstoff‐Transport: Vorteile, Nachteile und Alternativen

“…[189] [190] PVP kann durch freie radikalische Polymerisation von Vinylpyrrolidon sowie durch kontrollierte radikalische Polymerisation hergestellt werden. [174] Die zweite Methode ermöglicht niedrige PDI-Werte unterhalb von 1.2, [182,[191][192][193] variable Endgruppen [182,194] [195] Das erfolgreichste Konjugat, ein 28-kDa-PHPMADoxorubicin-Copolymer (8.5 Gew.-%; Doxorubicin PK1; klinische Studie Nr. FCE 28068 Phase III; Schema 4), wurde für mehrere Krebsarten getestet (Tabelle 3) und zeigte dabei Wirkung bei NSCLC, kolorektalen Tumoren und Mammakarzinomen.…”

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

“…Nitrogen atom of PNVP can easily form coordinate bonds with lots of drugs, especially protein and polypeptides, which can be used as carrier of drugs. Recently, Ranucci et al (17)(18)(19)(20)reported the synthesis of hydroxyl-terminated PNVP oligmers via free radical polymerization in isopropyl alcohol (IPA), using cumene hydroperoxide as the initiator.…”