scholarly journals Experiment Research on Bonding Effect of Poly(lactic-co-glycolic acid) Device by Surface Treatment Method

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Xiaopeng Wang ◽  
Kun Lian ◽  
Tianning Chen
Keyword(s):  
Contact Angle ◽  
Surface Treatment ◽  
Uv Irradiation ◽  
Bonding Temperature ◽  
Treatment Method ◽  
Degradable Polymer ◽  
Bonding Effect ◽  
Experimental Surface ◽  
Surface Contact Angle ◽  
Plga Film

According to the low temperature and high effective bonding problem of microdevices made of degradable polymer PLGA, chemical, plasma, and UV irradiation method are used to study the experimental surface treatment of PLGA films and microdevices bonding process. The results show that all three methods can reduce the surface contact angle of PLGA films, the contact angle increases with time at room temperature, and the PLGA films contact angle is almost unchanged under refrigeration. The PLGA film bonding temperature is significantly reduced after UV irradiation, and the bonding interfaces also generate diffusion cross linking layer are dense and uniform.

scholarly journals Self-Cleaning Polyester Fabric Prepared with TiOF2 and Hexadecyltrimethoxysilane

Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 387
Author(s):  
Euigyung Jeong ◽  
Heeju Woo ◽  
Yejin Moon ◽  
Dong Yun Lee ◽  
Minjung Jung ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Contact Angle ◽  
Treatment Method ◽  
Polyester Fabric ◽  
Anatase Tio2 ◽  
The Self ◽  
Water Contact ◽  
Direct Fluorination ◽  
Tomato Ketchup ◽  
Self Cleaning

In this study, self-cleaning polyester (PET) fabrics were prepared using TiOF2 and hexadecyltrimethoxysilane(HDS) treatment. TiOF2 was synthesized via direct fluorination of a precursor TiO2 at various reaction temperatures. The prepared PET fabrics had superior photocatalytic self-cleaning properties compared with anatase TiO2/HDS-treated PET fabrics under UV and sunlight with 98% decomposition of methylene blue. TiOF2/HDS-treated PET fabrics also had superior superhydrophobic self-cleaning properties compared with anatase TiO2/HDS-treated PET fabrics with a 161° water contact angle and 6° roll-off angle. After the self-cleaning tests of the non-dyed TiOF2/HDS-treated PET fabrics, we prepared dyed TiOF2/HDS-treated PET fabrics to test practical aspects of the treatment method. These PET fabrics were barely stained by tomato ketchup; even when stained, they could be self-cleaned within 4 h. These results suggest that practical self-cleaning PET fabrics with superhydrophobicity and photocatalytic degradation could be prepared using TiOF2/HDS-treatment.

SrTiO3 Functional Ceramics Thin Film Prepared by Self-Assembled Monolayers with the Liquid Phase Deposition Method on Silicon Substrates

2010 ◽  
Vol 105-106 ◽  
pp. 270-273
Author(s):  
Hui Jun Ren ◽  
Guo Qiang Tan ◽  
Hong Yan Miao ◽  
Ya Yu Song ◽  
Ao Xia
Keyword(s):  
Thin Film ◽  
Contact Angle ◽  
Liquid Phase ◽  
Deposition Temperature ◽  
Precursor Solution ◽  
Self Assembled Monolayers ◽  
Silicon Substrates ◽  
Liquid Phase Deposition ◽  
Assembled Monolayers ◽  
Surface Contact Angle

In this article, (NH4)2TiF6, SrNO3 and H3BO3 were used as raw materials to prepare the precursor solution with the ratio of AHFT/SN/BA=1:1:3. The thin films of SrTiO3 were fabricated on the functional silicon substrates (100) by self-assembled monolayers (SAMs) with the liquid phase deposition (LPD). This article also studied the effects of wet state and the deposition temperature of the precursor solution before and after the functionalization of silicon substrate on the thin film growth. The results indicated that after the immersion in OTS for 30min, the surface contact angle of the silicon substrate changed from 24.64° to 100.91°. The substrate appeared hydrophobic property and it was irradiated by UV light for 30min. Then the surface contact angle of the substrate decreased to 5.00°. The substrate appeared hydrophilicity. The concentration of the precursor solution was 0.025 mol/L, the deposition temperature was 40°C and the deposition time was 9h, which were all helpful to SrTiO3 crystallization. XRD and SEM were used to characterize the physical phase of thin film and surface morphology at 600 °C with annealing and heat retaining for 2h. The results indicated that the thin film prepared by the mono-crystal Si substrate was SrTiO3 thin film with better crystalline. On the crystal surfaces of (110), (100), (200) and (211), there appeared the obvious diffraction peaks. The SrTiO3 grains on the surface had the clear outline and were regular and long columnar crystals.

scholarly journals Acid Etching as Surface Treatment Method for Luting of Glass-Ceramic Restorations, part 1: Acids, Application Protocol and Etching Effectiveness

2018 ◽  
Vol 6 (3) ◽  
pp. 568-573 ◽  
Author(s):  
Emilija Barjaktarova-Valjakova ◽  
Anita Grozdanov ◽  
Ljuben Guguvcevski ◽  
Vesna Korunoska-Stevkovska ◽  
Biljana Kapusevska ◽  
...  
Keyword(s):  
Surface Treatment ◽  
Glass Ceramic ◽  
Hydrofluoric Acid ◽  
Treatment Method ◽  
Acid Etching ◽  
Etching Time ◽  
Ceramic Surface ◽  
Adhesive Luting ◽  
Ceramic Restorations ◽  
Etching Effect

AIM: The purpose of this review is to represent acids that can be used as surface etchant before adhesive luting of ceramic restorations, placement of orthodontic brackets or repair of chipped porcelain restorations. Chemical reactions, application protocol, and etching effect are presented as well.STUDY SELECTION: Available scientific articles published in PubMed and Scopus literature databases, scientific reports and manufacturers' instructions and product information from internet websites, written in English, using following search terms: “acid etching, ceramic surface treatment, hydrofluoric acid, acidulated phosphate fluoride, ammonium hydrogen bifluoride”, have been reviewed.RESULTS: There are several acids with fluoride ion in their composition that can be used as ceramic surface etchants. The etching effect depends on the acid type and its concentration, etching time, as well as ceramic type. The most effective etching pattern is achieved when using hydrofluoric acid; the numerous micropores and channels of different sizes, honeycomb-like appearance, extruded crystals or scattered irregular ceramic particles, depending on the ceramic type, have been detected on the etched surfaces.CONCLUSION: Acid etching of the bonding surface of glass - ceramic restorations is considered as the most effective treatment method that provides a reliable bond with composite cement. Selective removing of the glassy matrix of silicate ceramics results in a micromorphological three-dimensional porous surface that allows micromechanical interlocking of the luting composite.

Surface Modification of Asymmetric Polysulfone Membrane by UV Irradiation

2014 ◽  
Vol 70 (2) ◽  
Author(s):  
Sutthisa Konruang ◽  
Thawat Chittrakarn ◽  
Suksawat Sirijarukul
Keyword(s):  
Contact Angle ◽  
Surface Modification ◽  
Functional Groups ◽  
Uv Irradiation ◽  
Water Flux ◽  
Inversion Method ◽  
Asymmetric Structure ◽  
Polysulfone Membrane ◽  
Polar Functional Groups ◽  
Polysulfone Membranes

The effects of ultraviolet (UV) irradiation for surface modification of hydrophobic asymmetric polysulfone membranes have been investigated. The asymmetric polysulfone (PSF) membranes were prepared by phase inversion method using 19%-25% of PSF in two solvents, viz. dimethylacetamide (DMF) and Acetone (Ac) collectively. The surface of asymmetric polysulfone membranes were modified by UV ray with 254 and 312 nm wavelength. Chemical and physical properties of the untreated and the treated membranes were characterized. Scanning electron microscope (SEM) was used to determine asymmetric structure of polysulfone membranes. Contact angle device was used to analyzed the effected of UV ray treatment on hydrophilicity of membranes surface. Polar functional groups introduced by UV irradiation were examined using FTIR. The water flux was measured under a pressure of 500 kPa to 2,500 kPa with a feed temperature of 25°C. It was shown that asymmetric polysulfone membranes were produced and the UV ray treatment significantly alters the hydrophilicity of membranes surface indicated by the reduction of water contact angle with increasing treatment time. The FTIR analysis showed the formations of polar functional groups such as hydroxyl and carbonyl groups. Consequently, the surface of asymmetric polysulfone membranes was changed from hydrophobic to hydrophilic by UV irradiation leading to the enhancement of the water flux.

scholarly journals The Improvement of Wear Characteristics on 316L Stainless Steel by Dual Surface Treatment Method

2019 ◽  
Vol 9 (1) ◽  
pp. 5826-5831
Keyword(s):  
Stainless Steel ◽  
Wear Resistance ◽  
Surface Treatment ◽  
316L Stainless Steel ◽  
Treatment Method ◽  
Case Depth ◽  
Dual Processes ◽  
Boron Diffusion ◽  
Shot Blasting ◽  
Wear Evaluation

Stainless steel is used widespread in various industries, but it has poor wear resistance. Therefore, this study aims to investigate the wear resistance of enhanced surface of 316L stainless steel by applying the combination of surface treatments that consist of shot blasting followed by paste boronizing. Glass beads with diameter 250 microns and the blasting pressure of 6 bar has been used as the shot material in conducting shot blasting process. Paste boronizing process was conducted at temperature 950°C for 8 hours soaking. Data were collected and analyzed which concentrating on the samples’ microstructure, microhardness and wear evaluation. Shot blasting improves the case depth of boride layers formed after performing paste boronizing by boosting the boron diffusion owing to the grain refinement created by shot blasting. The ultimate combination of shot blasting and paste boronizing parameters enhance the case depth of the smooth and compact boride layers with high boron content. The hardness performance increase 624% compared to untreated 316L stainless steel which also highly improve the wear resistance of the material. In this investigation, these dual processes of surface treatment which are shot blasting and paste boronizing can be applied in fabricating the improved 316L stainless steel for industrial usages.

Characterization of Wafer Level Metal Thermo-Compression Bonding

2010 ◽  
Vol 2010 (DPC) ◽  
pp. 002326-002360
Author(s):  
Erkan Cakmak ◽  
Bioh Kim ◽  
Viorel Dragoi
Keyword(s):  
Surface Treatment ◽  
Metal Surface ◽  
Bonding Temperature ◽  
Transient Liquid Phase ◽  
Bonding Process ◽  
Bending Test ◽  
Strength Analysis ◽  
Mems Devices ◽  
Wafer Level ◽  
Bond Quality

The process of wafer-level bonding is being successfully used to form MEMS devices. Wafer level bonding may be realized by different methods such as thermo compression, transient liquid phase, anodic, glass frit, or polymer bonding. These methods have different requirements and the choice of wafer level bonding method is defined by the application type. Metal TCB has a wide variety of applications with materials of choice including Au, Cu and Al. 3D electrical connections are created by the use of Cu-Cu TCB; while CMOS MEMS devices may be realized by Al-Al TCB. In this study the wafer level bonding process of Cu-Cu and Al-Al TCB are characterized. The effects and significance of various bonding process parameters and surface treatment methods are reported on the final bond interfaces integrity and strength. Analysis methods include SAM, SEM, AFM, and four point bending test. Al-Al TCB samples were investigated on the interfacial adhesion energy and bond quality. IAE and bond quality were found to be positively correlated with bonding temperature. A bonding temperature of 500 °C or greater is necessary to obtain bond strengths of 8–10 J/m2. A positive relation between IAE and bonding temperature was observed for Cu-Cu TCB. IAE's of greater then 10 J/m2 were obtained on bonded samples that do not show a post bond residual seam on the bonding interface. An acid based pre treatment was shown to impact the surface properties of the initial metal surface hence affecting the IAE. Post bond annealing processes showed the most significant impact on the IAE of the Cu-Cu TCB system. To obtain comparable IAE values the Al-Al TCB method requires a higher bonding temperature. However the Cu-Cu TCB is sensitive to the initial metal surface condition and requires surface treatment processes prior to bonding to obtain high quality bonding results.

scholarly journals Bacteria Death and Osteoblast Metabolic Activity Correlated to Hydrothermally Synthesised TiO2 Surface Properties

Molecules ◽  
2019 ◽  
Vol 24 (7) ◽  
pp. 1201 ◽  
Author(s):  
Alka Jaggessar ◽  
Asha Mathew ◽  
Tuquabo Tesfamichael ◽  
Hongxia Wang ◽  
Cheng Yan ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Properties ◽  
Metabolic Activity ◽  
Mechanical Stability ◽  
Antibacterial Properties ◽  
Mechanical Tests ◽  
Nanostructured Surfaces ◽  
Surface Contact Angle ◽  
Cellular Metabolic Activity ◽  
Structure Height

Orthopaedic surgery comes with an inherent risk of bacterial infection, prolonged antibiotic therapy and revision surgery. Recent research has focused on nanostructured surfaces to improve the bactericidal and osseointegrational properties of implants. However, an understanding of the mechanical properties of bactericidal materials is lacking. In this work, the surface properties of hydrothermal TiO2 nanostructured surfaces are investigated for their effect on bactericidal efficiency and cellular metabolic activity of human osteoblast cells. TiO2 nanostructures, approximately 307 nm in height and 14 GPa stiffness, were the most effective structures against both gram-positive (Staphylococcus aureus) and gram-negative (Pseudomonas aeruginosa) bacteria. Statistical analysis significantly correlated structure height to the death of both bacteria strains. In addition, the surface contact angle and Young’s modulus were correlated to osteoblast metabolic activity. Hydrophilic surfaces with a contact angle between 35 and 50° produced the highest cellular metabolic activity rates after 24 hours of incubation. The mechanical tests showed that nanostructures retain their mechanical stability and integrity over a long time-period, reaffirming the surfaces’ applicability for implants. This work provides a thorough examination of the surface, mechanical and wettability properties of multifunctional hydrothermally synthesised nanostructured materials, capable of killing bacteria whilst improving osteoblast metabolic rates, leading to improved osseointegration and antibacterial properties of orthopaedic implants.

scholarly journals The Reversible Giant Change in the Contact Angle on the Polysulfone and Polyethersulfone Films Exposed to UV Irradiation.

Langmuir ◽  
2009 ◽  
Vol 25 (8) ◽  
pp. 4828-4828
Author(s):  
Edward Bormashenko ◽  
Roman Pogreb ◽  
Gene Whyman ◽  
Yelena Bormashenko ◽  
Rachel Jager ◽  
...  
Keyword(s):  
Contact Angle ◽  
Uv Irradiation
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