Inner Pore of Porous Fluoropolymer to Hydrophilic by using UV Light and H20 Vapor

1998 ◽  
Vol 544 ◽  
Author(s):  
Shinsuke Ito ◽  
Masataka Murahara
Keyword(s):  
Contact Angle ◽  
Excimer Laser ◽  
Water Permeability ◽  
Uv Light ◽  
Ethanol Solution ◽  
Oh Radicals ◽  
Arf Excimer Laser ◽  
Inner Pore

AbstractInner pores of porous PTFE was modified photochemically by using ArF excimer laser for improvement of water permeability. In this study, two modification methods are described. One is using ethanol solution, and another is H20 vapor as a reaction gas. These reaction sources were employed for modification of inner pores. In the case of using ethanol solution, the modified sample indicates both hydrophilication and oleophilication. On the contrary, the hydrophilic groups are substituted into the inner pore with H20 vapor. The hydrophilication of modified samples were evaluated by the measurement of contact angle with water and water permeability. The substituted OH radicals were inspected by ATR-FTIR measurement.

ArF Laser Induced Photochemical Substitution of OH Radicals into Teflon Surface Using Al(OH)3 Solution

1992 ◽  
Vol 279 ◽  
Author(s):  
M. Okoshi ◽  
H. Kashiura ◽  
T. Miyokawa ◽  
K. Toyoda ◽  
M. Murahara
Keyword(s):  
Contact Angle ◽  
Excimer Laser ◽  
Laser Light ◽  
Water Solution ◽  
Sample Surface ◽  
Oh Radicals ◽  
Xps Analysis ◽  
Air Atmosphere ◽  
Arf Excimer Laser ◽  
Teflon Film

ABSTRACTOH radicals were photochemically substituted for fluorine atoms in the teflon surface by using an ArF excimer laser light and an Al(OH)3 solution. This method is simple and can be performed in air atmosphere. In the process, the teflon film was placed on the Al(OH)3 which were dissolved in NaOH water solution; the ArF excimer laser light was irradiated the sample surface and the solution. By irradiating the laser, the surface was defluorinated by the aluminium atoms photodissociated from the Al(OH)3 solution, and the dangling bonds which were formed in the defluorinated surface combined with the OH radicals also photodissociated. The hydrophilic property of the photomodified surface was evaluated by the measurement of the contact angle with water. The defluorination and the OH radicals substitution were inspected by the XPS analysis and the ATR-FTIR measurement.

High Resolution Displacement of Functional Groups onto Fluorocarbon Resin Surface by Using ArF Excimer Laser

1996 ◽  
Vol 451 ◽  
Author(s):  
T. Shimizu ◽  
M. Murahara
Keyword(s):  
Contact Angle ◽  
High Resolution ◽  
Laser Beam ◽  
Thin Layer ◽  
Functional Groups ◽  
Excimer Laser ◽  
Laser Fluence ◽  
Large Area ◽  
Three Solutions ◽  
Arf Excimer Laser

ABSTRACTA Fluorocarbon resin surface was selectively modified by irradiation with a ArF laser beam through a thin layer of NaAlO2, B(OH)3, or H2O solution to give a hydrophilic property. As a result, with low fluence, the surface was most effectively modified with the NaAlO2 solution among the three solutions. However, the contact angle in this case changed by 10 degrees as the fluence changed only 1mJ/cm2. When modifying a large area of the surface, high resolution displacement could not be achieved because the laser beam was not uniform in displacing functional groups. Thus, the laser fluence was successfully made uniform by homogenizing the laser beam; the functional groups were replaced on the fluorocarbon resin surface with high resolution, which was successfully modified to be hydrophilic by distributing the laser fluence uniformly.

Comparison with Amino Group and Hydrophilic Group for Protein Afftnity by Excimer Laser Induced Functional Groups Substitution Onto Pet Film

2002 ◽  
Vol 735 ◽  
Author(s):  
Hitoshi Omuro ◽  
Masato Nakagawa ◽  
Hiroaki Fukuda ◽  
Masataka Murahara
Keyword(s):  
Contact Angle ◽  
Functional Groups ◽  
Excimer Laser ◽  
Bonding Strength ◽  
Functional Group ◽  
Laser Light ◽  
Artificial Ligament ◽  
Untreated Sample ◽  
Ammonia Gas ◽  
Arf Excimer Laser

ABSTRACTPET has been widely used for medical materials such as an artificial ligament. However, the affinity of tissues is no good. To compensate this, the mesh formed PET has clinically been used for artificial ligament intruding tissue into mesh. However, this method has not shown sufficient affinity with the tissue; that is, the initial adapting strength of the material and tissue is weak. · The artificial ligament must be biocompatible to contact blood and tissue. The foregoing artificial ligament, however, doesn't satisfy the biocompatibility. ·Thus, we have modified the PET surface into hydrophilic by substituting NH2 or OH functional groups. Firstly, an ArF excimer laser light was irradiated the PET with water on top. The OH functional group was substituted on the PET surface by this photochemical reaction. Secondly, the ArF excimer laser light was irradiated the PET in ammonia gas ambient. In this photochemical reaction, the NH2 functional group was substituted on the PET surface.· In this study, the untreated sample had the contact angle with water of 80 degrees and the bonding strength with protein of only 1.0kg/cm2. The contact angle of the modified sample improved to 40 degrees and the bonding strength, to 23kg/cm2. When treated in ammonia gas, the contact angle also improved to 40 degrees; however, the bonding strength was almost the same as that of the untreated sample.It was confirmed that the affinity of the PET for water and protein could be controlled by increasing or decreasing the substitution concentration of OH and NH2 functional groups on the surface.

Electrowetting–induced photochemical surface modification onto fluorocarbon

2005 ◽  
Vol 890 ◽  
Author(s):  
Hiroyuki Anai ◽  
Yuji Sato ◽  
Masataka Murahara
Keyword(s):  
Contact Angle ◽  
Surface Modification ◽  
Laser Irradiation ◽  
Excimer Laser ◽  
High Voltage ◽  
Sample Surface ◽  
Hydrophilic Property ◽  
Voltage Application ◽  
Arf Excimer Laser ◽  
The Moment

ABSTRACTThe PTFE was modified into hydrophilic with 1/100 of the shots number required to obtain the same contact angle with water by the laser irradiation alone, when irradiating an ArF excimer laser on the sample surface at the moment of applying a 6 kV to the water placed on the PTFE surface to decrease the contact angle with water.A plasma treatment method is widely used for plastic surface modification, but the hydrophilic property generated by this method fades away soon. On the other hand, we have previously reported that the ArF excimer laser light was applied on a sample surface in the presence of water to substitute hydrophilic groups, which was modified to have a long–lasting hydrophilic property. This method, however, needed 3000 to 10000 shots of the laser irradiation, and it is less economical compared with the plasma processing that requires only one–minute irradiation. There is an electro–wetting method, in which the contact angle with water decreases temporarily when a high voltage is applied between the water and the sample, but the contact angle is restored to its original position when stopping the voltage application.Thus, we demonstrated the surface modification of PTFE maintaining the hydrophilic property for a long period with only 100 shots, by irradiating the ArF excimer laser on the sample at the moment when the wettability became high by the electro–wetting method. Water was placed in the gap between the silica glass and the PTFE to create a thin liquid layer with capillary phenomenon. A high voltage (6 kV) of direct current (DC) or alternating current (AC) was applied on the gap, and the ArF excimer laser was vertically irradiated on the sample surface. The water was photo–dissociated to produce H and OH. At the same time, the C—F bond of the PTFE was also photo–dissociated, and the F atom bonded to the H atom to produce HF. The OH group united with the dangling bond of C, which resulted in modifying the PTFE surface to be hydrophilic.To evaluate the wettability of the modified sample, the contact angle with water was measured. Improving the contact angle with water from 110 degrees for the untreated sample to 50 degrees for the treated sample had needed 10000 shots at the laser fluence of 5 mJ/cm2. By combined high voltage application and ArF excimer laser irradiation treatments, however, the 50–degree contact angle was yielded with 500 shots, 1/20 of 10000, when applying the DC of 6 kV, and with 100 shots only, 1/100 of 10000, when applying the AC of 6 kV. Moreover, the modified sample was observed for a change in contact angle with passage of time. The contact angle was 60 degrees after applying the high voltage, and 110 degrees when stopped. On the other hand, the sample modified by combined the high voltage application and ArF excimer laser irradiation maintained the 50–degree contact angle for one month after stopping the voltage application.

Arf Excimer Laser and Xe2· Excimer Lamp Induced Photochemical Fluorination of Polyimide Film

1998 ◽  
Vol 544 ◽  
Author(s):  
T. Ikegame ◽  
M. Murahara
Keyword(s):  
Contact Angle ◽  
Chemical Composition ◽  
Excimer Laser ◽  
Water Repellency ◽  
Polyimide Film ◽  
Dangling Bond ◽  
Weak Point ◽  
Excimer Lamp ◽  
Chemically Modified ◽  
Arf Excimer Laser

AbstractOnly one weak point of all aromatic group polyimide surface was changed to water repellency. Polyimide surface was photo-chemically modified to be fluorinate with ArF excimer laser and Xe2 · excimer lamp irradiation. To promote the photo- chemical reaction, Xe2· excimer lamp was employed to produce CFn. radical from CF4 gas. Simultaneously, ArF excimer laser was irradiated on the polyimide surface to dissociate C-H bond. Dangling bond of C was reacted with CF, radical and produced C-CF, on the polyimide surface. By this modification, polyimide surface was changed to water repellency. As a result, polyimide surface was photo-chemically modified to fluorinate with CF4 gas pressure of 100Torr, the Xe2 excimer lamp of 7mW/cm2, and the ArF excimer laser of 30mJ/cm2, 10Hz and 3000shots, the contact angle with water was 134 degrees. And chemical composition of the photo-modified polyimide surface was inspected by ATR-FTIR spectra measurement.

Synthesis of HTCMgFe for the degradation of indigo carmine through heterogeneous photo-Fenton treatment

MRS Advances ◽  
2020 ◽  
Vol 5 (62) ◽  
pp. 3273-3282
Author(s):  
I. Cosme-Torres ◽  
M.G. Macedo-Miranda ◽  
S.M. Martinez-Gallegos ◽  
J.C. González-Juárez ◽  
G. Roa-Morales ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Treatment Time ◽  
Uv Light ◽  
Indigo Carmine ◽  
Oh Radicals ◽  
Absorption Bands ◽  
Chromophore Group ◽  
X Ray ◽  
Catalytic Sites ◽  
Scanning Electron

AbstractThe heterogeneous catalyst HTCMgFe was used in the degradation of the IC, through the heterogeneous photo-fenton treatment, this material in combination with H2O2 and UV light degraded the dye in 30 min at pH 3. As the amount of HTCMgFe increases the degradation it was accelerated because there are more active catalytic sites of Fe2+ on the surface of the material, which generates a greater amount of •OH radicals. The HTCMgFe was characterized by infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray energy dispersive elemental analysis (EDS). The UV-vis spectrum shows that the absorption bands belonging to the chromophore group of the IC disappear as the treatment time passes, indicating the degradation of the dye.

Sign in / Sign up

Export Citation Format

Share Document