酸性条件下多巴胺表面接枝改性聚酰亚胺薄膜

Polyimide film modified by grafting dopamine onto the surface under acidic conditions

在酸性条件下,使用交联剂1乙基(3二甲基氨基丙基)碳二亚胺盐酸盐(EDC)将多巴胺接枝到聚酰亚胺(PI)薄膜表面,研究接枝条件对薄膜表面结构和还原性能的影响。采用傅里叶变换红外光谱仪(FT-IR)、接触角测量仪、原子力显微镜(AFM)、扫描电子显微镜(SEM)、能谱仪(EDS)、X线衍射仪(XRD)等对薄膜表面结构和性能进行表征。结果表明:在酸性条件下PI薄膜表面接枝的多巴胺,可极大地减缓多巴胺氧化自聚合反应,在薄膜表面保留了大量的酚羟基。经过24 h接枝后,PI薄膜表面的水接触角由45.35°降到7.43°,并且平均面粗糙度(R_(a))和均方根粗糙度(R_(ms))由原来的1.48和1.92 nm分别提高到14.7和19.8 nm;在不使用任何还原剂的条件下在PI薄膜上镀Ag,表面Ag的质量分数和原子分数分别为75.47%和29.40%,并且表面Ag是具有良好结晶度的Ag颗粒。

Under acidic conditions,the crosslinking agent 1-ethyl-(3-dimethylaminopropyl)carbodiimide hydrochloride(EDC)was used to graft dopamine onto the surface of polyimide(PI)film.The effects of grafting conditions on the surface structure and reduction performance of the film were studied.Fourier transform infrared spectrometer(FT-IR),contact angle measuring instrument,atomic force microscope(AFM),scanning electron microscope(SEM),energy spectrometer(EDS),X-ray diffractometer(XRD),etc.were used to measure the surface structure and performance characterization of the film.Results showed that the grafted dopamine on the surface of PI film under acidic conditions greatly slowed down the oxidative self-polymerization of dopamine and retained a large number of phenolic hydroxyl groups on the surface of the film.After 24 hours of grafting,the water contact angle on the PI film surface dropped from 45.35°to 7.43°,the average surfaceroughness(R_(a))and root mean square roughness(R_(ms))had been increased from the 1.48 and 1.92 nm to 14.7 and 19.8 nm,respectively.The PI film was plated with Ag without using any reducing agent,and the mass fraction and atomic fraction of Ag on the surface were 75.47% and 29.40%,respectively.In addition,these Ag particles had good crystallinity.