低温等离子接枝改性聚乳酸支架的亲水性

聚乳酸具有良好的生物相容性以及可降解性能,但其强疏水性能一定程度上限制了其在可降解支架领域的应用。本研究利用氩气(Ar)低温等离子技术在PDLLA血管支架表面接枝亲水性的聚合物聚乙烯吡咯烷酮(PVP)以及聚醋酸乙烯酯(PVAc)。接触角测试表明,经等离子接枝的材料表面接触角由原来的105°~110°可降至22°,由强疏水性变为亲水性。体外细胞粘附性实验表明:等离子处理后的材料表面表现出亲水性质,其细胞的粘附性也得以明显提高,更加有利于细胞在其表面的生长。

等离子接枝处理对高分子量聚乙烯纤维浸润性的影响

超高分子量聚乙烯纤维(UHMWPE纤维)经过苯乙烯和甲基丙烯酸低温等离子接枝处理后,通过观察悬挂在纤维上的乙二醇的液滴的形态,可计算纤维和液体表面的接触角;接触角的变小,说明纤维的浸润性能得到明显的改善。

改性玄武岩纤维对矿渣水泥砂浆性能的影响

采用低温等离子接枝方式对玄武岩纤维(BF)进行改性处理,研究了接枝介质(水、丙烯酸、乙醇)和处理时间(10、20、30、40 min)对BF表面接触角和比表面积的影响,并研究了接枝改性BF对矿渣水泥砂浆力学性能的影响。结果表明:经过接枝改性处理后,BF的表面亲水性增强,粗糙度增大;当接枝介质为水、丙烯酸、乙醇时,试件的28 d抗压强度与空白组和掺未改性BF试件相比均变化不大,但28 d抗折强度均明显增大,其中,接枝介质为乙醇改性BF试件的28 d抗折强度最高,韧性最好,这是由于接枝改性BF与基体之间的黏结力增大所导致的。

Low-Temperature Plasma Induced Grafting of 2-Methacryloyloxyethyl Phosphorylcholine onto Poly(tetrafluoroethylene) Films

Modification of poly(tetrafluoroethylene)(PTFE) films with 2-methacryloyloxyethyl phosphorylcholine(MPC) was performed by low-temperature plasma treatment and grafting polymerization.Surface properties of PTFE were characterized by attenuated total reflectance Fourier transform infrared(ATR-FTIR) spectra,X-ray photoelectron spectroscopy(XPS) ,and static contact angle.The results show that MPC has been grafted onto PTFE film surface successfully.Contact angle for the modified PTFE films in the water decreased from 108°to 58.25°,while surface energy increased from 17.52 mN/m to 45.47 mN/m.The effects of plasma treatment time,monomer concentration and grafting time on degree of grafting were determined.In the meanwhile,blood compatibility of the PTFE films was studied by checking thrombogenic time of blood plasma.