A New Approach for the Synthesis of pH‐Responsive Cross‐Linked Micelles from a Poly(glycidyl methacrylate)‐Based Functional Copolymer

Abstract

An amphiphilic poly(ethylene glycol)methyl ether‐block‐poly(glycidyl methacrylate) (MPEG‐b‐PGMA) diblock copolymer is first synthesized via atom transfer radical polymerization. Epoxy groups of this precursor block copolymer are converted to hydroxyl and tertiary amine residues by reacting with diethyl amine over a ring‐opening reaction. The resulting diblock copolymer is poly(ethylene glycol)methyl ether‐block‐poly(3‐diethylamino‐2‐hydroxypropyl methacrylate) (MPEG‐b‐PDEAHPMA). Micellar solution of this diblock copolymer is prepared at pH 12.0 in aqueous media. At high pH (12.0), core– shell micelles are formed with PDEAHPMA‐core and MPEG‐shell. PDEAHPMA blocks have both hydroxyl and tertiary amine groups that provide reactivity against divinyl sulfone (DVS) and a response to solution pH, respectively. Cross‐linking of hydroxyl groups of PDEAHPMA chains in the micelle core is successfully achieved by adding DVS. At pH 2.0, the DEAHPMA‐core of core cross‐linked (CCL) micelles becomes protonated and hence swelling is observed. The effect of varying the DVS concentrations is also studied. The micelle formation of diblock copolymer and its response to solution pH are investigated by using surface tensiometer, 1H NMR spectroscopy, and dynamic light scattering (DLS) techniques. CCL micellar structure and its response to solution conditions are investigated with transmission electron microscopy and DLS studies, respectively.

Post-polymerization modification reactions of poly(glycidyl methacrylate)s

“…[17][18][19][20][21][22][23][24][25][26][27][28][29] Furthermore, cross-linked systems are not covered. [30][31][32][33][34] The synthesis of the backbone itself is not discussed and the reader is referred to a number of important publications in this regard. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] Other polymer backbones that carry a side-chain epoxide functionality are important as is seen in the works of Harth, Dove, He, Siegwert, and Theato.…”

Stimuli-Responsive Polymers Providing New Opportunities for Various Applications

“…In addition, swelling of different aggregates (micelle, vesicle etc.) and gels (macrogel, microgel and nanogel) is among the important behaviors observed (Figure 4d) [26,98,109,[116][117][118]. Wetting, thickening of the polymer layer, change in pore size and change in charge are encountered in brush polymers, films and membranes (see Figures 4e and 4f) [119][120][121][122][123][124][125].…”

“…The increase of hydrophilicity in the polymer chain provides important behaviors [8,15]. When these polymer chains are used in the producti-on of various block copolymers as seen in Figure 4c, it is possible to obtain various amphiphilic block copolymers and thus various self-assembly behaviors (spherical micelle [16,17], flower [18,19], vesicle [16,20,21], wormlike [22,23]) which is a very remarkable behavior [24][25][26]. The related aggregate structures can reversibly dissolve, swell or shrink depending on the pH of the medium (Figure 4d) [27][28][29][30][31].…”

Preparation and catalytic properties of modified PGMA‐based pH‐responsive hydrogel films as a novel template for in situ synthesis of Au, Ag, and Au:Ag nanoparticles

“…Glycidyl methacrylate (GMA) monomer, often used to produce functional polymers, is very reactive, cheap, and suitable for various polymerization reactions . Various secondary amines cause the ring‐opening reaction to the epoxy groups of GMA, which leads to the production of tertiary amine and hydroxy‐based bifunctional polymers . We have already investigated the modification of poly(glycidyl methacrylate) (PGMA)‐containing polymers with various secondary amines (1‐methylpiperazine, diethylamine, and morpholine) and their behaviors in aqueous solutions .…”

“…Various secondary amines cause the ring‐opening reaction to the epoxy groups of GMA, which leads to the production of tertiary amine and hydroxy‐based bifunctional polymers . We have already investigated the modification of poly(glycidyl methacrylate) (PGMA)‐containing polymers with various secondary amines (1‐methylpiperazine, diethylamine, and morpholine) and their behaviors in aqueous solutions . These studies also produced the quaternary products of (co)polymers containing 2‐hydroxy‐3‐methyl piperazinepropyl methacrylate (HMPPMA units using 1‐methyl piperazine with different alkyl and aryl halides .…”