Synthesis and swelling behavior of pH‐responsive polyurethane/poly[2‐(diethylamino)ethyl methacrylate] hybrid materials

Abstract

Polyurethane (PU)/poly[2‐(diethylamino)ethyl methacrylate] hybrids, having a chemical bond between the PU and acrylic moieties and with different compositions, were prepared by the dispersion polymerization of 2‐(diethylamino)ethyl methacrylate (DEA) in the presence of preformed PU chains with polymerizable terminal vinyl groups. The PU dispersion was synthesized according to a prepolymer mixing process by the polyaddition of isophorone diisocyanate, poly(propylene glycol), 2‐hydroxyethyl methacrylate, and dimethylol propionic acid (DMPA). Then, it was dispersed in water by the prior neutralization of the carboxylic acid groups of DMPA with triethylamine, chain‐extended with ethylenediamine. The effect of the DEA content on the swelling properties (water uptake and dynamic swelling degree) at different pHs and at 37°C was determined. The samples were also characterized by Fourier transform infrared spectroscopy and modulated differential scanning calorimetry. The experimental results indicate a higher water uptake when the DEA content was increased on the hybrid materials and a significant change in the kinetics of swelling at pH 4 compared to those at pH 7. The water content of the hydrogels depended on the DEA content, and it was inversely proportional to the pH value. The pure PU film did not show important changes over the pH range examined in this study. The synthesized hybrids were useful as drug‐delivery, pH‐sensitive matrices. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39799.

Heavy metal ions removal from water using a smart polyurethane/acrylic hybrid

“…As was described in a previous work, PU/DEA hybrid systems have high water absorption capacity at pH 4.0, 150 wt. % and 280% for H70/30 and H50/50, respectively.…”

“…In PU film with copper incorporated, the band centered at 1655 cm −1 , corresponding to the carbonyl group of urea, is not observed; and the band corresponding to the amide II moves to smaller wavenumbers (from 1545 to 1533 cm −1 ). The N‐H band assigned to the free N‐H stretching vibration and hydrogen‐bonding N‐H stretching vibration, show a narrow and a shift from 3343 to 3325 cm −1 , suggesting a decrease in freedom of movement . On the contrary, no significant changes are detected in C‐O‐C vibration bands of the urethane and polyetherdiol (between 1175 and 1000 cm −1 ).…”

“…A detailed synthesis of PU/DEA hybrids was reported in a previous work . Briefly, in a 1 L six‐neck separable flask, PPG1000 and DMPA were charged and the mixture heated to 90 °C and bubbled dried air for 60 min.…”

“…Generally, monomers of the methacrylate family are those chosen as responsive monomers and sometimes the same monomer can play those two functions. It is also sought to complement the system with a supporting polymer that improves the performance of the system in terms of stability, durability, mechanical properties, etc …”

“…We have reported the synthesis and characterization of news pH‐sensitive hybrid polymers of polyurethane (PU) and 2‐(diethyl amino) ethylmethacrylate (DEA) with adequate film and mechanical properties and with potential applications as drug delivery systems . The possibility of forming complexes between metal ions and the amino functional groups of the hybrids makes of interest the analysis, characterization and evaluation of these responsive polymers and generate favorable expectations for their use as heavy metal uptake systems.…”