Carbon nanocoils (CNCs) were synthesized by the catalytic pyrolysis of acetylene over a mixture of Fe and SnO2 particles in a chemical vapor deposition (CVD) apparatus. The effects of reaction temperature, the composition of Fe and SnO2 in the catalyst, and the ratio of acetylene (C2H2) to helium (He) gas were examined. An optimum output was obtained when the Fe/SnO2 ratio was 2/1, the flow rates of C2H2 and He gases were 150 and 700 sccm, respectively, and the reaction temperature was 700°C. Under these conditions, the CNCs were of 80% purity, with average coil diameters of 750 nm, fiber diameters of 300 nm and pitches of approximately 750 nm. The CNC yield weighed up to 60 times that of the catalyst in 10 min.

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Objective: To develop a rapid method for the modification of polysulfone with ammonium sulfamate with the assistance of Ar ion irradiation with a multi-source cluster deposition apparatus. These surfaces mimicking the structure of heparin, a bioactive molecule, have a high anti-thrombosis property. Experimental Design: Polysulfone film, setting on a turning holder, was irradiated by Ar ions during bombardment with ammonium sulfamate clusters. The Ar ion source serves for the activation of a polymer surface and a cluster ion source supplies ammonium sulfamate molecules to react with the activated surface. After thorough washing with de-ionized sterile water, the modified surfaces were evaluated in terms of the contact angle of water, elemental composition, and binding state on electron spectroscopy for chemical analysis and platelet adhesion with platelet rich plasma. Results: The modification of polysulfone decreased the contact angle of water on surfaces from 82.6 ° down to 34.5 °. Ammonium, amine, sulfate, and thiophene combinations were formed on the modified surfaces. The adhesion numbers of the platelet were decreased to one tenth compared to the original surface. The same process was also applied to other polymers such as polyethylene, polypropylene, and polystyrene and similar outcomes were also observed. Conclusion: The primary studies showed successful modification of polysulfone with ammonium sulfamate with the assistance of Ar ion irradiation. Since the same concept can also be applied to other materials with various substrates, combined with the features of no solvent and no topographic changes, this method might be developed into a promising way for modification of polymeric materials.

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