Waterborne polyurethane containing spiropyran groups(SPU) has been prepared by polycondensation of isophorone diisocyanate (IPDI), polytetrahydrofuran glycol (PTMG), dimethylol propionic acid (DMPA), 1,4-butanediol (BD), trimethylolpropane (TMP) and 1-(2-Hydroxyethyl)-3,3-dimethylindolino-6′-nitrobenzopyrylospiran(SP). Fourier transform infrared spectroscopy (FT-IR), Thermogravimetric analysis (TG), Scanning electron microscope (SEM) were utilized to characterize SPU films for their chemical structure, thermal stability, microscopic structure. The kinetics of photochromic behavior of SPU dispersion and film has also been investigated. The dispersion and film showed a very good photochromic effect. The decoloration rate of the SPU dispersion and film follow the kinetic of a first order reaction. The fatigue resistance of SPU film is better than that of its dispersion.
Chang-Lei Liu,Gang Wu,Si-Chong Chen,Jiao You,Yu-Zhong Wang
Poly( p -dioxanone)-block-polyethylene glycol diblock copolymers functionalized with pyrene moieties (Py-PPDO-b-PEG) at the chain ends of PPDO blocks were synthesized for preparing anisotropic micelles with improved stability. The micellization and crystallization of the copolymers were investigated by nano differential scanning calorimetry (Nano DSC), transmission electron microscopy (TEM), UV–vis spectrophotometery, fluorophotometer, and dynamic light scattering (DLS), respectively. The results indicated that the aggregation of pyrene induced by intermolecular interaction lead to micellization of Py-PPDO-b-PEG at much lower concentrations than those of PPDO-b-PEG copolymers without pyrene moieties. The aggregation of pyrene moieties may also serve as nucleation agent and therefore enhance the crystallization rate of PPDO blocks. Fluorescence measurements by using Nile Red as the fluorescent agent indicated that the micelles of Py-PPDO-b-PEG have high stability and load capacity for hydrophobic molecules.
危险品化学品经营许可证（带存储）