Synthesis and Properties of Poly(N‐isopropylacrylamide‐co‐acrylamide) Hydrogels

Abstract

Poly (N‐isopropylacrylamide‐co‐acrylamide) [Poly(NIPAAm‐co‐AAm)] with different feed ratios were obtained by radiation polymerization using Co60γ‐rays. Swelling equilibrium data in various media: deionized water, aqueous NaCl solutions and different pH buffer solutions, were determined. It appeared that the lower critical transition temperature (LCST) of the hydrogels increased with an increasing acrylamide content and decreased with increasing ionic strength. Moreover, LCST was affected by pH.

Fundamentals and applications of acrylamide based microgels and their hybrids: a review

“…Various techniques like Photo correlation spectroscopy, 12 Transmission electron microscopy (TEM), 8 Dynamic light scattering (DLS), 1 UV-visible spectroscopy (UV-vis), 13 Fourier transform infrared spectroscopy (FTIR), 42 Scanning electron microscopy (SEM), 43 Raman spectroscopy (RS), 8 Energy dispersive X-ray spectroscopy (EDX), 44 Nuclear magnetic resonance spectroscopy (NMR), 45 Differential mechanical analysis (DMA), 46 Laser light scattering spectrometry (LLS), 9 Differential scanning calorimetry (DSC) 13 and Atomic force microscopy (AFM) have been reported to characterize P(NIPAM-Am) microgel particles. Photon correlation spectroscopy/DLS is used for determination of hydrodynamic size and size distribution of polymer microgel particles.…”

“…NiPAm and Am with some ionic co-monomer based hybrid microgels have also been extensively used as catalysts in different reactions due to high surface-to-volume ratio of inorganic nanoparticles loaded into the polymeric network. 4,13,20,26,27,42 P(NIPAM-AAm) microgels may be an ideal carrier for nanoparticles to be used for catalysis due to inertness of functionalities of polymeric network. Pendant isopropyl and amide groups of NIPAM and Am units keep the nanoparticles x inside the network without any aggregation.…”

Magnetothermally-responsive Nanomaterials: Combining Magnetic Nanostructures and Thermally-Sensitive Polymers for Triggered Drug Release

“…The LCST of a poly (alkylacrylamide) gel, such as PNIPAAm, can be altered by the judicious selection of comonomers that impart an increase or decrease in the polymer hydrophilicity (98,99). In general, adding hydrophilic comonomers to the hydrogel increases the LCST; thus, gels that combine NIPAAm with hydrophilic comonomers such as acrylic acid or acrylamide have been developed with LCSTs in the range of 35 to over 50°C, depending on the ratio of monomers used in the polymerization (99)(100)(101). Other polymers that display some thermosensitivity near physiological conditions include hydroxypropyl cellulose (102), Pluronic ® triblock copolymer surfactants and block copolymers (103,104), poly(dimethylaminoethyl methacrylate) (105) and elastin-like peptides (106).…”

Developmental toxicity assessment of thermoresponsive poly(N‐isopropylacrylamide‐co‐acrylamide) oligomers in CD‐1 mice

“…Another important feature of PNIPAAm is the possibility of modifying its lower critical solution temperature by copolymerization. By adding hydrophobic (Bae et al, 1990) or hydrophilic (Chen et al, 2005) comonomers to the reaction mixture, the lower critical solution temperature can be adjusted so that this transition occurs at a more desirable temperature, allowing a drug to be released with a heating or cooling trigger.…”