Preparation of stimuli‐responsive nanogels of poly [2‐(dimethylamino) ethyl methacrylate] by heterophase and microemulsion polymerization using gamma radiation

Abstract

Poly [2‐(dimethylamino) ethyl methacrylate], PDMAEMA, was synthesized by heterophase polymerization at 70°C using sodium dodecylsulfate (SDS) as stabilizer and potassium persulfate (KPS) as the initiator. Conversions were 60%, polymer content 18%, and intensity average particle diameter, Dp, 32 nm. γ‐rays irradiation of PDMAEMA nanolatexes and DMAEMA/H2O/SDS microemulsions using ethyleneglycol dimethacrylate produced nanogels responding to temperature and pH. Nanogels shrinked as temperature increased, swelled excessively in acidic solutions (maximum Dp: 498 nm) and deswelled (minimum Dp: 257 nm) in basic solutions for the case of the nanogels obtained from PDMAEMA nanolatexes. pH response to swelling is due to protonation of amine groups in the backbone of PDMAEMA in acidic conditions leading to electrostatic interactions in the nanogel. POLYM. ENG. SCI., 54:1625–1631, 2014. © 2013 Society of Plastics Engineers

Synthesis and Characterization of Stimuli-Responsive Poly(2-dimethylamino-ethylmethacrylate)-Grafted Chitosan Microcapsule for Controlled Pyraclostrobin Release

“…The release profile of pyraclostrobin under three different pH values of 3.7, 5.7, and 7.3 at 30 ± 0.5 °C is shown in Figure 8 . At pH 3.7, the cumulative release reached up to 40% after the first 7 h, and continuously increased to about 95% after 48 h; at pH 5.7, the cumulative release attained 30% and 80% after 7 and 48 h respectively; at pH 7.3, the cumulative release attained 67% after 48 h. These results clearly demonstrated that the cumulative release of pyraclostrobin was higher in acidic medium in comparison with that in the basic and neutral solution, which is directly proportional to the swelling ratio of the copolymers [ 38 ]. As the microcapsules’ exposures to release media, the entrapped pesticide passes into the external receiving medium by crossing the polymeric matrix.…”

Preparation of 2‐(dimethylamino) ethyl methacrylate copolymer micelles for shape memory materials

“…It is well known that poly(2‐(dimethylamino)ethyl methacrylate) (pDMAEMA) is widely used as a biomaterials double hydrophilic copolymer and environmentally sensitive coating due to its unique chemical structure containing–N(CH 3 ) 2 functional groups , which can be further quaternized or betainized . The literature reveals that the functional monomer 2‐(dimethylamino)ethyl methacrylate (DMAEMA) has been widely used to design stimuli‐responsive hydrogels, micelles, brushes, and other functional membranes grafted onto various substrates . In addition to their responsiveness to pH and temperature, DMAEMA‐based copolymers can also respond to external stimuli such as ion strength, selected ions and other factors in solution .…”

A temperature‐responsive polyurethane and its biocompatible and biodegradable nanohydrogels with uniform cross‐linking networks

“…Interest in stimuli-responsive polymers has lasted for the decades, and a large number of researches have been done to develop stimuliresponsive polymers and study their properties of responsivity [1][2][3][4][5], because of their potential applications in many significant fields such as drug delivery, smart surfaces, artificial muscles, and biosensors [1,[6][7][8]. Various stimuli were introduced to responsive polymers, mainly including temperature, pH, light, ionic strength, and redox reactions [9][10][11][12][13].…”