Synthesis of poly(glycidol)‐block‐poly(N‐isopropylacrylamide) copolymers using new hydrophilic poly(glycidol) macroinitiator

Abstract

New, water soluble poly(glycidol) (PGl) macroinitiators for atom transfer radical polymerization (ATRP) were synthesized. This new class of macroinitiators were prepared in a three‐step process. First, series of well‐defined ω‐hydroxyl functional poly(glycidol acetal)s with different molecular weights was synthesized via anionic polymerization followed by quantitative termination of anionically growing active sites. End capping was achieved by treatment of living chain ends with water. The living nature of the system and termination reaction is discussed. In the second stage, monofunctional poly(glycidol acetal)s were functionalized by esterification with 2‐chloropropionyl chloride. Finally, selective deprotection (hydrolysis) of acetal protective groups was performed. As simultaneous partial cleavage of ester bond of attached ATRP moieties was unavoidable, the final functionality of macroinitiator calculated from 1H NMR varied in the range 85–95%. The obtained (2‐chloropropionyl) poly(glycidol) macroinitiator with DP = 55 and 90% functionality was successfully used in ATRP polymerization of N‐isopropylacrylamide (NIPAAm) at room temperature in the DMF/water mixture. Linear block copolymers with relatively narrow molecular weight distribution and controlled composition were obtained and characterized with 1H NMR and SEC‐MALLS measurements. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2488–2499, 2008

Synthesis and degradation of biomedical materials based on linear and star shaped polyglycidols

“…Based on our own results and those presented in the literature PEEGE blocks can be prepared in a well controlled manner up to a molecular weight of M n = 30,000 ([M]/[I] ≈ 200) 32–34. It is assumed, that chain transfer to the monomer inhibits the synthesis of higher molecular weight polyglycidols via anionic polymerization.…”

“…The latter possibility, the introduction of functionality into the polymeric structure, has been scarcely investigated, but has in our opinion a great potential to regulate degradation rates. Regarding functionality, polyglycidol has been shown to be an interesting and versatile polymer 15, 31, 34, 74, 105, 106…”

Synthetic and Physicochemical Aspects of Advanced Stimuli‐Responsive Polymers

“…Water-soluble poly(glycidol) (PGl) macroinitiators for ATRP have been prepared and their ability to form block copolymers with NIPAAm and 4-VP has been proven [63,64]. On the basis of such polymers, a new method for the synthesis of smart nanohydrogels under additives-free conditions and at high solid content was investigated.…”

This much we do know: Sano conduit closure with the Amplatzer vascular plug

“…Combining external control over structure and physical properties will offer the possibility capable of both tunable transformation and controlled release of drugs. It would be of great benefit to develop novel stimuli‐responsive micelles self‐assembled in aqueous media in drug delivery system 10–13…”