Enhancement of the surface hydrophilicity of biodegradable poly （D,L-lactic acid） （PLA） films is studied. The PLA films were treated by nitrogen plasma （PLA-N2） and nitro- gen/hydrogen plasma （PLA-N2/H2）, resp...Enhancement of the surface hydrophilicity of biodegradable poly （D,L-lactic acid） （PLA） films is studied. The PLA films were treated by nitrogen plasma （PLA-N2） and nitro- gen/hydrogen plasma （PLA-N2/H2）, respectively. The surface properties and microstructure of PLA-N2 and PLA-N2/H2 were studied by static contact angle measurement, surface free energy calculation, X-ray photoelectron spectroscopy （XPS） and atomic force microscopy （AFM）. It is confirmed that the surface hydrophilicity of PLA-N2 and PLA-N2/H2 was higher than that of pristine PLA, and the surface hydrophilicity of PLA-N2 films was better than that of PLA-N2/H2.展开更多
An atmospheric pressure argon plasma brush with air addition is employed to treat polyethylene terephthalate(PET)surface in order to improve its hydrophilicity.Results indicate that the plasma plume generated by the p...An atmospheric pressure argon plasma brush with air addition is employed to treat polyethylene terephthalate(PET)surface in order to improve its hydrophilicity.Results indicate that the plasma plume generated by the plasma brush presents periodically pulsed current despite a direct current voltage is applied.Voltage-current curve reveals that there is a transition from a Townsend discharge regime to a glow one during one discharge period.Optical emission spectrum indicates that more oxygen atoms are produced in the plume with increasing air content,which leads to the better hydrophilicity of PET surface after plasma treatment.Besides,an aging behavior is also observed.The hydrophilicity improvement is attributed to the production of oxygen functional groups,which increase in number with increasing air content.Moreover,some grain-like structures are observed on the treated PET surface,and its mean roughness increases with increasing air content.These results are of great importance for the hydrophilicity improvement of PET surface with a large scale.展开更多
Surfaces of optical elements are deposited by antireflection coatings (ARCs) to decrease the reflection of light. Surface needs treatment before depositing the ARC one of treatment processes by plasma for adhesion imp...Surfaces of optical elements are deposited by antireflection coatings (ARCs) to decrease the reflection of light. Surface needs treatment before depositing the ARC one of treatment processes by plasma for adhesion improvement and surface hardening. A comparison of RF and DC glow discharges treated CR-39 polymer films gives insight into the mechanism of these surface processes. The surface properties of the plasma-treated samples are examined by microscopy techniques include contact angle measurements, scanning electron microscopy (SEM), atomic force microscopy (AFM), infrared (IR) spectroscopy and refractive index measurements. Results show that the plasma treatment modifies the polymer surface in both composition and morphology. It is found that the surface wettability is enhanced after plasma treatment. It is found that, RF plasma is more effective than DC plasma in CR-39 surface modification, as it implants more oxygen atoms into the surface and makes the contact angle declining to a lower level.展开更多
基金supported by the Fundamental Research Funds for the Central Universities (Nos. GK200901023, GK201004001)
文摘Enhancement of the surface hydrophilicity of biodegradable poly （D,L-lactic acid） （PLA） films is studied. The PLA films were treated by nitrogen plasma （PLA-N2） and nitro- gen/hydrogen plasma （PLA-N2/H2）, respectively. The surface properties and microstructure of PLA-N2 and PLA-N2/H2 were studied by static contact angle measurement, surface free energy calculation, X-ray photoelectron spectroscopy （XPS） and atomic force microscopy （AFM）. It is confirmed that the surface hydrophilicity of PLA-N2 and PLA-N2/H2 was higher than that of pristine PLA, and the surface hydrophilicity of PLA-N2 films was better than that of PLA-N2/H2.
基金supported by National Natural Science Foundation of China(Nos.11875121,11575050 and51977057)the Midwest Universities Comprehensive Strength Promotion Project+4 种基金the Natural Science Foundation of Hebei Province,China(Nos.A2019201100,A2020201025)College Hundred Outstanding Innovative Talent Support Program of Hebei Education Bureau(No.SLRC2017021)Post-graduate’s Innovation Fund Project of Hebei Province(Nos.CXZZBS2019023,CXZZBS2019029)the Natural Science Interdisciplinary Research Program of Hebei University(No.DXK201908)Post-graduate’s Innovation Fund Project of Hebei University(No.HBU2021bs011)。
文摘An atmospheric pressure argon plasma brush with air addition is employed to treat polyethylene terephthalate(PET)surface in order to improve its hydrophilicity.Results indicate that the plasma plume generated by the plasma brush presents periodically pulsed current despite a direct current voltage is applied.Voltage-current curve reveals that there is a transition from a Townsend discharge regime to a glow one during one discharge period.Optical emission spectrum indicates that more oxygen atoms are produced in the plume with increasing air content,which leads to the better hydrophilicity of PET surface after plasma treatment.Besides,an aging behavior is also observed.The hydrophilicity improvement is attributed to the production of oxygen functional groups,which increase in number with increasing air content.Moreover,some grain-like structures are observed on the treated PET surface,and its mean roughness increases with increasing air content.These results are of great importance for the hydrophilicity improvement of PET surface with a large scale.
文摘Surfaces of optical elements are deposited by antireflection coatings (ARCs) to decrease the reflection of light. Surface needs treatment before depositing the ARC one of treatment processes by plasma for adhesion improvement and surface hardening. A comparison of RF and DC glow discharges treated CR-39 polymer films gives insight into the mechanism of these surface processes. The surface properties of the plasma-treated samples are examined by microscopy techniques include contact angle measurements, scanning electron microscopy (SEM), atomic force microscopy (AFM), infrared (IR) spectroscopy and refractive index measurements. Results show that the plasma treatment modifies the polymer surface in both composition and morphology. It is found that the surface wettability is enhanced after plasma treatment. It is found that, RF plasma is more effective than DC plasma in CR-39 surface modification, as it implants more oxygen atoms into the surface and makes the contact angle declining to a lower level.
