N-异丙基丙烯酰胺(NIPA)和聚(乙二醇)甲基醚甲基丙烯酸酯(PEGMEMs)的热敏共聚物P1-P5通过无表面活性剂沉淀聚合(SFPP)在70°C下使用过硫酸铵(APS)合成。通过电导率评价聚合过程。P1-P5在18-45°C范围内的流体动力学直径和多分散指数(PDI),通过动态光散射(DLS)进行评估,在18°(nm):26.07±0.54(PDI0.65±0.03),68.00±1.10(PDI0.56±0.02),45.12±0.57(PDI0.51±0.03),62.78±0.40(PDI0.53±0.003),和92.95±1.56(PDI0.60±0.04),分别。较低的临界溶液温度范围为31至33°C。电泳迁移率估计zeta电位在18-45°C范围内,在18°C,P1-P5分别为(mV):-4.64±1.30,-6.91±2.67,-5.85±3.17,-2.28±0.30和-3.60±0.96。用衰减全反射傅里叶变换红外光谱(ATR-FTIR)对聚合物进行了表征,H核磁共振(1HNMR),热重分析(TGA/DTA),差示扫描量热法(DSC),和粉末X射线衍射分析(PXRD)。获得稳定的无定形聚合物。我们得出的结论是,共聚单体链的长度非线性地影响所获得的热敏聚合物纳米结构的性能。
Thermosensitive copolymers P1-P5 of N-isopropylacrylamide (NIPA) and poly(ethylene glycol) methyl ether methacrylates (PEGMEMs) were synthesized via surfactant-free precipitation polymerization (SFPP) using ammonium persulfate (APS) at 70 °C. The polymerization course was evaluated by the conductivity. The hydrodynamic diameters and the polydispersity indexes (PDI) of P1-P5 in the 18-45 °C range, which were assessed via dynamic light scattering (DLS), were at 18° (nm): 26.07 ± 0.54 (PDI 0.65 ± 0.03), 68.00 ± 1.10 (PDI 0.56 ± 0,02), 45.12 ± 0.57 (PDI 0.51 ± 0.03), 62.78 ± 0.40 (PDI 0.53 ± 0.003), and 92.95 ± 1.56 (PDI 0.60 ± 0.04), respectively. The lower critical solution temperatures ranged from 31 to 33 °C. The electrophoretic mobilities estimated the zeta potential in the 18-45 °C range, and at 18 °C, they were (mV): -4.64 ± 1.30, -6.91 ± 2.67, -5.85 ± 3.17, -2.28 ± 0.30, and -3.60 ± 0.96 for P1-P5, respectively. The polymers were characterized by Attenuated Total Reflectance Fourier-Transform Infrared spectroscopy (ATR-FTIR), H nuclear magnetic resonance (1H NMR), thermogravimetric analysis (TGA/DTA), Differential Scanning Calorimetry (DSC), and powder X-ray diffraction analysis (PXRD). Stable amorphous polymers were obtained. We conclude that the length of the co-monomer chain nonlinearly influences the properties of the obtained thermosensitive polymer nanostructures.