沉积时间对聚醚醚酮表面类金刚石薄膜的结构和性能的影响

Effect of Deposition Time on Structure and Performance of Diamond-like Carbon Films on PEEK

采用直流磁控溅射技术在聚醚醚酮(PEEK)表面制备不同厚度的类金刚石(DLC)薄膜,研究了沉积时间对其表/界面结构、组分、疏水、力学和光透过性能的影响。结果表明,在平均沉积速率为5.71 nm/min的条件下,随着沉积时间的延长DLC薄膜的厚度线性增大、碳原子的致密性提高、界面互锁结构增强,而界面结合强度逐渐降低。沉积时间≤15 min时,基体结构的影响使拟合计算出的I_(D)/I_(G)值为0.23~0.25和sp^(2)/sp^(3)比值较小(0.58~0.74);沉积时间>15 min时基体的影响较小,I_(D)/I_(G)值突增大至0.81,sp^(2)/sp^(3)值也比较大(0.96~1.12)。沉积时间的延长使PEEK基体的温度逐渐升高,使膜内的sp^(2)/sp^(3)值逐渐增大。薄膜表面的氧含量先降低然后趋于平缓,部分C=O转化为C-O。随着沉积时间的延长,PEEK/DLC复合薄膜的硬度、弹性模量及防紫外线和阻隔红外线性能都逐渐提高,其表面粗糙度和疏水性的变化趋势是先提高后降低。沉积时间为32 min的薄膜,其表面粗糙度和水接触角达到最大值,分别为495 nm和108.29°。

Diamond-like carbon (DLC) films with different thickness (11.26~230.93 nm) were prepared on polyether ether ketone (PEEK) via direct current magnetron sputtering in the time ranging from 2 to 40 min.The effect of deposition time on the structure and composition of surface and interface,as well as the surface hydrophobic,the mechanical and optical transmittance properties of composite films PEEK/DLC were systematically studied.Results show that with the increase of deposition time the film thickness will be enhanced linearly with an average deposition rate of 5.71 nm/min.The density of C atoms and the interface interlocking structure gradually increase,while the interface adhesion decreases with time.By fitting peaks of Raman and XPS spectra,it is found that when the time≤15 min,the I_(D)/I_(G)value by data fitting remains at 0.23~0.25 and the ratio of sp^(2)/sp^(3) is low (0.58~0.74) due to the influence of substrate.When the time>15 min,as the substrate effect becomes weak the I_(D)/I_(G)value has a great increase (to 0.81),and the sp^(2)/sp^(3) value turns to be high (0.96~1.12).Prolonging the time will lead to the rise of substrate temperature inducing the ascending of sp^(2)/sp^(3) ratio.While O content at the surface presents a low-flat trend and part of C=O bonds transformed into C-O bonds.The hardness,elastic modulus,the anti-ultraviolet and infrared barrier properties of PEEK/DLC composite films will rise over time,while the surface roughness and hydrophobicity both have a trend from high to low,reaching a maximum surface roughness and water contact angle of 495 nm and 108.29° at 32 min,respectively.