Resnik Matic, Zaplotnik Rok, Mozetic Miran, Vesel Alenka
Jozef Stefan International Postgraduate School, Jamova 39, Ljubljana 1000, Slovenia.
Jozef Stefan Institute, Jamova 39, Ljubljana 1000, Slovenia.
Materials (Basel). 2018 Feb 21;11(2):311. doi: 10.3390/ma11020311.
The fluorination of the polymer polyethylene terephthalate in plasma created from SF₆ or CF₄ gas at various pressures was investigated. The surface was analysed by X-ray photoelectron spectroscopy and water contact angle measurements, whereas the plasma was characterized by optical emission spectroscopy. The extent of the polymer surface fluorination was dependent on the pressure. Up to a threshold pressure, the amount of fluorine on the polymer surface and the surface hydrophobicity were similar, which was explained by the full dissociation of the SF₆ and CF₄ gases, leading to high concentrations of fluorine radicals in the plasma and thus causing the saturation of the polymer surface with fluorine functional groups. Above the threshold pressure, the amount of fluorine on the polymer surface significantly decreased, whereas the oxygen concentration increased, leading to the formation of the hydrophilic surface. This effect, which was more pronounced for the SF₆ plasma, was explained by the electronegativity of both gases.
研究了在由六氟化硫（SF₆）或四氟化碳（CF₄）气体在不同压力下产生的等离子体中对聚对苯二甲酸乙二酯聚合物进行氟化的情况。通过X射线光电子能谱和水接触角测量对表面进行分析，而通过发射光谱对等离子体进行表征。聚合物表面氟化程度取决于压力。在达到阈值压力之前，聚合物表面的氟含量和表面疏水性相似，这可以通过SF₆和CF₄气体的完全解离来解释，导致等离子体中氟自由基浓度较高，从而使聚合物表面被氟官能团饱和。高于阈值压力时，聚合物表面的氟含量显著降低，而氧浓度增加，导致形成亲水性表面。这种效应在SF₆等离子体中更为明显，这是由两种气体的电负性所解释的。
