Surface biocompatible modification of polyurethane by entrapment of a macromolecular modifier.

A macromolecular biocompatible surface modifier for polyurethane (PU), namely, polyurethane-block-poly(vinylpyrrolidone) (PU-b-PVP) copolymer, was synthesized by coupling hydroxyl-terminated PVP with diisocyanate-terminated poly(ethylene glycol) using 1,6-hexamethylene diisocyanate (HDI) as coupling agent. The chemical structure and molecular weight of the synthesized copolymer were systematically characterized by nuclear magnetic resonance spectrum ((1)H NMR), Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). The synthesized surface modifier was blended with PU and effectively increased the hydrophilicity of PU.

Surface biocompatible modification of polypropylene by entrapment of polypropylene-block-poly(vinylpyrrolidone).

A macromolecular surface modifier, namely polypropylene-block-poly(vinylpyrrolidone) copolymer, could diffuse preferably onto the surface and effectively increased the biocompatibility of PP. The blood and cell compatibilities of PP and PP-b-PVP/PP blend films were evaluated by determination of the extent of platelet adsorption, plasma recalcification time, hemolysis rate and cell proliferation using smooth muscle cells from rabbit aorta. The results revealed that the blood and cell compatibilities of PP were improved significantly by entrapment of a few PP-b-PVP copolymers in PP.

[Quantitative analysis of surface composition of polypropylene blends using attenuated total reflectance FTIR spectroscopy].

The surface composition and structure of solid organic polymers influence many of their properties and applications. Oligomers such as poly(ethylene glycol) (PEG), poly(methyl methacrylate) (PMMA) poly(butyl methacrylate) (PBMA) and their graft copolymers of polybutadiene and polypropylene were used as the macromolecular surface modifiers of polypropylene. The compositions on surface and in bulk of the polypropylene (PP) blends were determined quantitatively using attenuated total reflectance FTIR spectroscopic (ATR-FTIR) technique with a variable-angle multiple-reflection ATR accessory and FTIR measurements, respectively.