化学法粗化医用聚氨酯支架管表面的润湿性研究

针对医用植入支架管在临床使用过程中存在的体液结垢问题,研究医用聚氨酯支架管表面的化学法粗化及其润湿性。采用化学法粗化医用聚氨酯材料,测量粗化后聚氨酯材料的接触角和表面形貌,分析液滴重力对接触角的影响,并探讨影响粗化效果的因素,如粗化液的种类、粗化液混合比、粗化液浓度、粗化温度、粗化时间等对粗化后导管表面润湿性的影响。结果表明:聚氨酯材料表面接触角随着液滴重力的增加,呈先增大后减小的趋势;粗化有助于提高聚氨酯导管表面疏水性能,其中三氧化铬粗化后导管接触角比高锰酸钾粗化后接触角更大;接触角随着三氧化铬与浓硫酸混合比、粗化温度、粗化时间三者的增大,均呈现先增大后减小的趋势,而随着三氧化铬浓度的增大逐渐增大。得到最佳的粗化工艺参数为:三氧化铬与浓硫酸的混合比2∶1,三氧化铬浓度80 g/L,粗化温度50℃,粗化时间30 min。

Wettability of Medical Polyurethane Stent Surfaces Roughened by Chemical Method

For the demand of anti-encrustation to medical implant stent in the course of clinic application,the chemical roughening and wettability of medical polyurethane stent were studied.The medical polyurethane was roughened by chemical method,and the contact angle and surface shape of roughened polyurethane were measured.The effect of drop weight to contact angle was analyzed,and the effect of coarsening factors to wettability of roughened polyurethane were discussed,such as roughening fluid,mixing ratio,concentration,temperature and time.The results show that the contact angle of polyurethane surface is increased first and then decreased with the adding of drop weight.The chemical roughening helps to enhance the hydrophobic performance,and the contact angle of polyurethane roughened by chromium trioxide is greater than that by potassium permanganate.With the increasing of mixing ratio,temperature and time,the contact angle is increased firstly and then decreased.But the contact angle is increased with the increasing of chromium trioxide concentration.The optimal roughening parameters are roughing temperature of 50 ℃,roughening time of 30 min,chromium trioxide concentration of 80 g/L,sulfuric acid and chromium trioxide mixture ratio of 2∶ 1.