Moticam2000

The number-averaged molecular weight (M_n) and polydispersity index (M_w/M_n) of PNIPAAms were determined by size-exclusion chromatography (SEC) with poly(methyl methacrylate) calibration (standard samples were purchased from Agilent, Santa Clara, California, USA). DMF containing 10 mM LiBr was used as an eluent, and the measurement was conducted at 40 °C using three polystyrene gel columns (PLgel 5 μm MIXED-C, PLgel 3 μm MIXED-E and Shodex KF-805L) connected to a Shimadzu LC-10AD precision pump, a Shimadzu RID-10A refractive index detector, and a Shimadzu SPD-10A UV–VIS detector set at 250 nm (Shimadzu, Kyoto, Japan). ¹H NMR analysis was performed with a JEOL JNM-LA400 spectrometer (JEOL, Akishima, Japan), operating at 399.65 MHz. The swelling degree of PNIPAAm gels in water was determined from the diameter of cylindrical gels using a digital microscope (MOTICAM2000, Shimadzu, Kyoto, Japan). The swelling degree was calculated by (d/d₀)³; d₀ is the inner diameter of the capillary and d is the equilibrium diameter at predetermined temperature.

Number-average molecular weight (M_n) and polydispersity index (M_w/M_n) of polymers were determined by size-exclusion chromatography (SEC) in DMF containing 10 mM LiBr at 40 °C using three polystyrene gel columns (PLgel 5 μm MIXED-C, PLgel 3 μm MIXED-E and Shodex KF-805L) that were connected to a Shimadzu LC-10AD precision pump (Kyoto, Japan) and a Shimadzu RID-10A refractive index detector (Kyoto, Japan). The columns were calibrated against standard poly(methyl methacrylate) samples (Agilent, Santa Clara, California, USA). ¹H NMR spectra were recorded on a JEOL JNM-LA400 spectrometer (Akishima, Japan), operating at 399.65 MHz. The degree of swelling was determined by measurement of the diameter of the cylindrical gels. The gels were immersed in water at predetermined temperatures, and the equilibrium diameter at given temperature, d, was measured using a digital microscope (MOTICAM2000, Shimadzu, Kyoto, Japan). The degree of swelling was calculated by (d/d₀)³; d₀ is the inner diameter of the capillary used for the gel preparation. The shrinking rate was evaluated by temperature-jump experiment. The cylindrical gels were immersed in water at 5 °C until the gels reached to the equilibrium swollen state. Then, the gels were quickly transferred into the hot water at 50 °C, and the change of the diameter of the gel was observed.

A drop of the diluted emulsion was placed on a microscope slide and viewed using an optical microscope (Motic BA200, Shimadzu, Kyoto, Japan) fitted with a digital system (Moticam 2000, Shimadzu).