| Polyurethane has been used in various fields for its excellent mechanical properties and good hemocompatibility. Many research works have been done to Polyurethane all over the world. Such works include mechanical improvement, new fields for application and surface structure modification. In this article, it major includes two parts of works shown below.First, Polyurethane (PU) films were treated by toluene-2, 4-diisocyanate as to form free isocyanate groups (—NCO) on the membrane surfaces, and then the membranes were cooperated withγ-aminopropyltrimethoxysilane (KBE-903). So the external layer were trimethoxysilane groups, which can create compact and network state Si-O-Si cross-linked layer by hydrolysis reaction. PU films modified by each step were characterized by attenuated total reflectance (ATR) FT-IR spectroscopy, and X-ray photoelectron spectroscopy (XPS). The PU membranes treated by KBE-903 get higher hydrolysis resistance ability compared to the untreated PU membranes. The characteristic of this designed experiment was to obtain the material a variety of good original mechanical function via surface grafting modification.Second, after treatment of removing oil and cleaning the surface, Polyurethane membrane surface was activated by Toluene Diisocyanate (TDI), so as to form free isocyanate groups (—NCO) on the membrane surface. And Br group was grafted by the reaction of—NCO and the hydroxyl group of 2-Bromoethanol. Such Br group can initiate polymerization of Methacrylate via Atom transfer radial polymerization (ATRP), in the condition of Copper (I) Chloride (CuCl) and 2, 2-Bipyridine (Bpy). Kinetics study showed a linear increase in the grafting polymerization of Methacrylate with the reaction time, which was indicating that the chain growth from the surface is a 'living' process. The chemical composition and topography of each step modified Polyurethane membrane were detected by attenuated total reflectance spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS).
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