偕胺肟化SiO2/聚丙烯腈复合纤维膜的制备及其性能

Fabrication and properties of amidoxime-modified SiO2/polyacrylonitrile composite fibrous nonwovens

为构筑具有特殊表/界面性能的膜材料,利用静电纺丝技术制备SiO2/聚丙烯腈(PAN)复合纤维膜,然后经盐酸羟胺偕胺肟化处理赋予其超亲水及水下超疏油性能。借助场发射扫描电子显微镜、X射线能谱仪、傅里叶变换光谱仪及接触角测试仪等分析了纤维膜的微观形貌、结构和表/界面性质。结果表明:偕胺肟化改性后纤维膜表面有絮状物包覆,盐酸羟胺改性液最佳质量浓度为35~40 g/L,最佳改性温度为60℃,偕胺肟化SiO2/PAN纤维的平均直径为275 nm;改性后纤维膜表面Si和O元素质量分数为2. 13%和6. 60%,SiO2锚固在PAN纤维膜表面,且SiO2/PAN偕胺肟化成功;相比PAN纤维膜,SiO2/PAN纤维膜在60℃偕胺肟化后水润湿时间由5. 4 s缩短到0. 5 s,且水下油接触角达到(165. 2±1)°;偕胺肟化纤维膜断裂强度达4. 1 MPa,可满足油水分离的基本要求。

In order to construct membrane materials with special surface/interface properties,amidoxime-modified SiO2/polyacrylonitrile( PAN) nonwovens with highly hydrophilic and underwater super-hydrophobic surface were fabricated using electrospinning and amidoximation with hydroxylamine hydrochloride. The composite nonwovens were characterized by the field emission scanning electron microscopy,energy dispersive X-ray spectroscopy,Fourier transform infrared spectrometer and contact angle tester. The results show that the surfaces of the amidoxime-modified nanofibrous nonwovens are covered with floccule,the average diameters of amidoxime-modified SiO2/PAN nonwovens are 275 nm at the optimal volume concentration of 35-40 g/L and the best modification temperature is 60 ℃ . The fraction content of Si and O elements on the surface of the modified nanofibrous nonwovens are 2. 13%and 6. 60%,receptively. All these results demonstrate that SiO2 particles are successfully deposited onto the PAN nonwovens. Comparing with PAN nonwovens( wetting time 5.4 s),after 60 ℃ amidoximation,the wetting time of SiO2/PAN nonwovens is shortened to 0. 5 s. Moreover,the underwater oil contact angle of as-prepared composited nonwovens reach( 165. 2 ± 1) °. The breaking strength of amidoximemodified nanofibrous nonwovens is 4. 1 MPa,and it meet the basic requirements of oil-water separation.