Ayazbayeva Aigerim Ye, Shakhvorostov Alexey V, Gussenov Iskander Sh, Seilkhanov Tulegen M, Aseyev Vladimir O, Kudaibergenov Sarkyt E
Laboratory of Functional Polymers, Institute of Polymer Materials and Technology, Almaty 050019, Kazakhstan.
Department of Chemical and Biochemical Engineering, Satbayev University, Almaty 050013, Kazakhstan.
Nanomaterials (Basel). 2022 Jul 8;12(14):2343. doi: 10.3390/nano12142343.
Polyampholyte nanogels based on -isopropylacrylamide (NIPAM), (3-acrylamidopropyl) trimethylammonium chloride (APTAC) and 2-acrylamido-2-methyl-1-propanesulfonic acid sodium salt (AMPS) were synthesized via conventional redox-initiated free radical copolymerization. The resultant nanogels of various compositions, specifically [NIPAM]:[APTAC]:[AMPS] = 90:5:5; 90:7.5:2.5; 90:2.5:7.5 mol.%, herein abbreviated as NIPAM-APTAC-AMPS, NIPAM-APTAC-AMPS and NIPAM-APTAC-AMPS, were characterized by a combination of H NMR and FTIR spectroscopy, TGA, UV-Vis, DLS and zeta potential measurements. The temperature and salt-responsive properties of amphoteric nanogels were studied in aqueous and saline solutions in a temperature range from 25 to 60 °C and at ionic strengths (μ) of 10 to 1M NaCl. Volume phase transition temperatures (VPTT) of the charge-balanced nanogel were found to reach a maximum upon the addition of salt, whereas the same parameter for the charge-imbalanced nanogels exhibited a sharp decrease at higher saline concentrations. A wide bimodal distribution of average hydrodynamic sizes of nanogel particles had a tendency to transform to a narrow monomodal peak at elevated temperatures and higher ionic strengths. According to the DLS results, increasing ionic strength results in the clumping of nanogel particles.
基于N-异丙基丙烯酰胺(NIPAM)、(3-丙烯酰胺基丙基)三甲基氯化铵(APTAC)和2-丙烯酰胺基-2-甲基-1-丙磺酸钠盐(AMPS)的聚两性电解质纳米凝胶通过传统的氧化还原引发自由基共聚反应合成。所得各种组成的纳米凝胶,具体为[NIPAM]:[APTAC]:[AMPS]=90:5:5;90:7.5:2.5;90:2.5:7.5摩尔%,在此简称为NIPAM-APTAC-AMPS、NIPAM-APTAC-AMPS和NIPAM-APTAC-AMPS,通过1H NMR和FTIR光谱、TGA、UV-Vis、DLS和zeta电位测量进行表征。在25至60°C的温度范围内以及10至1M NaCl的离子强度(μ)下,在水溶液和盐溶液中研究了两性纳米凝胶的温度和盐响应特性。发现电荷平衡纳米凝胶的体积相变温度(VPTT)在添加盐时达到最大值,而电荷不平衡纳米凝胶的相同参数在较高盐浓度下急剧下降。纳米凝胶颗粒平均流体动力学尺寸的宽双峰分布在升高的温度和较高的离子强度下倾向于转变为窄单峰峰。根据DLS结果,增加离子强度会导致纳米凝胶颗粒聚集。