Development of nonfouling membranes to prevent nonspecific protein adsorption and platelet adhesion is critical for many biomedical applications. It is always a challenge to control the surface graft copolymerization of a highly polar monomer from the highly hydrophobic surface of a fluoropolymer membrane. In this work, the blood compatibility of poly(vinylidene fluoride) (PVDF) membranes with surface-grafted electrically neutral zwitterionic poly(sulfobetaine methacrylate) (PSBMA), from atmospheric plasma-induced surface copolymerization, was studied. The effect of surface composition and graft morphology, electrical neutrality, hydrophilicity and hydration capability on blood compatibility of the membranes were determined. Blood compatibility of the zwitterionic PVDF membranes was systematically evaluated by plasma protein adsorption, platelet adhesion, plasma-clotting time, and blood cell hemolysis. It was found that the nonfouling nature and hydration capability of grafted PSBMA polymers can be effectively controlled by regulating the grafting coverage and charge balance of the PSBMA layer on the PVDF membrane surface. Even a slight charge bias in the grafted zwitterionic PSBMA layer can induce electrostatic interactions between proteins and the membrane surfaces, leading to surface protein adsorption, platelet activation, plasma clotting and blood cell hemolysis. Thus, the optimized PSBMA surface graft layer in overall charge neutrality has a high hydration capability and the best antifouling, anticoagulant, and antihemolytic activities when comes into contact with human blood.

These results indicate that using cultured HCECs and functional biomaterials, PNIPAAm and gelatin, an effective cell sheet-based therapy can be developed for the treatment of corneal endothelium deficiency.

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Epoxy resins containing phosphorus and/or silicon are prepared from phosphorus/silicon‐containing epoxides and diamine curing agents. The flame‐retardant properties of the phosphorus/silicon‐containing epoxy were studied. Furthermore, the phosphorus–silicon synergistic effect on LOI enhancement and increasing flame retardancy of the epoxy materials were demonstrated. While under flame, phosphorus provides the tendency of char formation, and silicon provides the enhancement on thermal stability of the char, to show their individual benefit on flame retardancy. Introducing both phosphorus and silicon together in the epoxy resin composition brings the success of combining these two factors in a flame retardation mechanism. An LOI enhancement from 26 to 36 is observed for epoxy resins containing both phosphorus and silicon. Moreover, the synergistic effect of phosphorus–silicon on fire resistance can be further leveled up by using siloxane reagents to replace silanes. Epoxy resins with a composition of phosphorus epoxides and siloxane diamines exhibit a high LOI value of 41, to demonstrate the high synergistic efficiency of phosphorus and silicon on flame retardation. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1–7, 2000