Synthesis, properties of fullerene-containing polyurethane–urea and its optical limiting absorption

Hybrids of colloidal silica and waterborne polyurethane

“…The 13 C and 29 Si NMR spectra of the solid-state hybrids were determined (Bruker, AVANCE-400) with cross polarization combined with the magic angle spinning (CP/MAS) technique using 200-300 mg samples. The 13 C measured conditions of pulse width, recycle delay, contact time and number of scans are 5.5 µs, 5 s, 1000 µs, and 1486, respectively, at 100.6 MHz.…”

“…The 13 C measured conditions of pulse width, recycle delay, contact time and number of scans are 5.5 µs, 5 s, 1000 µs, and 1486, respectively, at 100.6 MHz. These conditions corresponding to 29 Si are 3 µs, 200 s, 1000 µs, and 294, respectively, at 79.4 MHz. The fracture surface of hybrid thin films were examined on the (Philips, XL-40FEG) field emission scanning electron microscope (SEM).…”

“…To gain more insight into the influence of WPU polymer chain on the silica, 29 Si CP/MAS NMR experiments of the colloidal silica and the prepared hybrids have been performed and shown in Fig. 5.…”

Controlled mechanical and swelling properties of urethane acrylate grafted calcium alginate hydrogels

“…The reason is that the grafted urethane acrylate interferes the arrangement of CaA chains and forms highly ordered crystal regions. The peak at 2Â (19.04 • ) is a typical urethane peak [18], which confirms urethane acrylate has been grafted onto calcium alginate.…”

Hybrid thin films derived from UV-curable acrylate-modified waterborne polyurethane and monodispersed colloidal silica

“…For pure WPU-AC, nearly amorphous diffraction peak is seen near 2! = 200 [31], indicating the crystalline of polyester segments. As the MSMASiO 2 content increases, the diffraction becomes weaker and broader, whereas this peak gradually shifts to the characteristics of pure silica.…”