scholarly journals Effect of Salicylic Acid and 5-Sulfosalicylic Acid on UV-Vis Spectroscopic Characteristics, Morphology, and Contact Angles of Spin Coated Polyaniline and Poly(4-aminodiphenylaniline) Thin Films

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
A. Sironi ◽  
D. Marinotto ◽  
C. Riccardi ◽  
S. Zanini ◽  
E. Guerrini ◽  
...  

Polyaniline and poly(4-aminodiphenyl)aniline have been prepared following two different synthetic protocols (a traditional method and a “green” method). Both the polymers have been spin coated with salicylic acid and 5-sulfosalicylic acid as the dopants, in order to obtain them in form of thin films. These materials have been characterized, thereof achieving important information on their water contact angles and surface morphology.

2015 ◽  
Vol 1131 ◽  
pp. 251-254
Author(s):  
Montri Aiempanakit ◽  
Chantana Salawan ◽  
Kamon Aiempanakit

The effect of continuous and discontinuous deposition time on the properties of TiO2 thin films deposited by reactive direct current magnetron sputtering (DCMS) on glass substrates was investigated. The deposition processes were designed for a condition of continuous deposition time D1 (60 min) and three conditions of discontinuous deposition time D2 (30 min × 2 times), D3 (15 min × 4 times), and D4 (1 min × 60 times). The crystal structure, surface morphology, and hydrophilicity of TiO2 thin films were characterized by X-ray diffraction, atomic force microscope, and water contact angle method, respectively. It was found that the increasing of discontinuous deposition time (conditions from D1 to D4) shows the changing of grain size from big grain size with spherical shape to small grain size with oval shape. The crystallinity of TiO2 films decrease with increasing the discontinuous deposition time. The water contact angles also decrease as a function of increasing discontinuous deposition time. These results may be explained from the accumulation of heat on the substrate which affected the phase composition and surface morphology of TiO2 thin films.


2019 ◽  
Vol 813 ◽  
pp. 37-42
Author(s):  
Amani Khaskhoussi ◽  
Luigi Calabrese ◽  
Edoardo Proverbio

Three different methods were used to obtain nature-inspired superhydrophobic surfaces on aluminum alloys: short-term treatment with boiling water, HF/HCl and HNO3/HCl concentrated solution etching. Afterwards a thin octadecylsilane film was deposited on all pre-treated surfaces. The surface morphology analysis showed that each method allow to obtain a specific dual nano/micro-structure. The corresponding water contact angles ranged from 160° to nearly 180°. The adhesion force between the water droplets and superhydrophobic surfaces were evaluated. The specimen etched with HF/HCl acid mixture solution showed the lowest adhesion. However, the boiling water treatment sample was characterized by the highest adhesion. Furthermore, the relationship between hydrophobic behavior and surface morphology was discussed compressively. In addition, the electrochemical measurements show that the different superhydrophobic surfaces have an excellent anti-corrosion performance evidencing promising results suitable to obtain large-scale nature-inspired superhydrophobic surfaces for several industrial applications.


Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 202 ◽  
Author(s):  
Chiara Mandolfino ◽  
Enrico Lertora ◽  
Carla Gambaro ◽  
Marco Pizzorni

Polyolefins are considered among the most difficult polymeric materials to treat because they have poor adhesive properties and high chemical barrier responses. In this paper, an in-depth study is reported for the low pressure plasma (LPP) treatment of neutral polypropylene to improve adhesion properties. Changes in wettability, chemical species, surface morphology and roughness of the polypropylene surfaces were evaluated by water contact angle measurement, X-ray photoelectron spectroscopy and, furthermore, atomic force microscopy (AFM). Finally, the bonded joints were subjected to tensile tests, in order to evaluate the practical effect of changes in adhesion properties. The results indicate that plasma is an effective treatment for the surface preparation of polypropylene for the creation of bonded joints: contact angles decreased significantly depending on the plasma-parameter setup, surface morphology was also found to vary with plasma power, exposure time and working gas.


Soft Matter ◽  
2017 ◽  
Vol 13 (36) ◽  
pp. 6152-6166 ◽  
Author(s):  
Jake McClements ◽  
Cosimo Buffone ◽  
Michael P. Shaver ◽  
Khellil Sefiane ◽  
Vasileios Koutsos

The self-assembly of poly(styrene-co-butadiene) random copolymers on mica surfaces was studied by varying solution concentrations and polymer molecular weights.


2005 ◽  
Vol 901 ◽  
Author(s):  
Phani Ratna Ayalasomayajula ◽  
S. Santucci

AbstractDevelopment of UV blocking thin films with effective cut-off features with steep edges and high transmission in the visible and IR region have been developed. The unique optical, mechanical and chemical properties of silica and ceria nanocomposites with surface functional groups making them most promising candidate for applications in opto-electronic, automotive, and aeronautic industries. On the other hand, highly hydro and oleophobic films are being actively considered in optical, automotive and aeronautic industries to increase adhesion and scratch, abrasion resistance properties. In order to fill the gap, and fulfill the requirements to meet both ends, it could be proved that morphological changes in the nanometer range influences the water contact angles and their hystersis of low energy materials. Nanocomposite films of SiO2 and CeO2 with surface functionalisation with decafluorooctly-triethoxy silane itself forms nano-hemispheres (similar to lotus leaf) at and above 100°C favoring an increase in water contact angle from 122° (25°C) to 145°(400°C). The structural, optical, and hydrophobic properties have been examined by employing X-ray diffraction, UV-visible spectroscopy, contact angle techniques, respectively. The cut-off behavior of the deposited and annealed nanocomposite thin films have been tuned by varying different amounts of CeO2 in SiO2.


2020 ◽  
Vol 21 (14) ◽  
pp. 4873
Author(s):  
Maria Laura Alfieri ◽  
Lucia Panzella ◽  
Youri Arntz ◽  
Alessandra Napolitano ◽  
Vincent Ball ◽  
...  

The tyrosinase-catalyzed oxidation of tyramine, leading to the deposition of pseudo-polydopamine (ψ-PDA) thin films, is disclosed herein as a superior technology for surface functionalization and coating at a neutral pH and at a low substrate concentration, compared to the standard autoxidative PDA coating protocols. Smooth ψ-PDA thin films of variable thickness up to 87 nm were obtained from 1 mM tyramine by varying tyrosinase concentrations (5–100 U/mL). Compared to the PDA films obtained by the similar enzymatic oxidation of 1 mM dopamine with tyrosinase (T-PDA), ψ-PDA displayed slower deposition kinetics, lower water contact angles in the range of 11°–28°, denoting higher hydrophilicity but similar UV-vis absorption profiles, as well as electrochemical properties and antioxidant activity. MALDI-MS analysis indicated for ψ-PDA a well defined pattern of peaks compatible with dopamine tetrameric structures degraded to a variable extent. The exposure to a tyramine solution of tyrosinase-loaded alginate spheres, or films deposited on glass or polyethylene, resulted in a rapid gel-confined ψ-PDA formation with no leakage or darkening of the solution, allowing the complete recovery and re-utilization of the unreacted tyramine. In contrast, an abundant PDA precipitation outside the gel was observed with dopamine under the same conditions. The ψ-PDA deposition by tyrosinase-catalyzed tyramine oxidation is thus proposed as a controllable and low-waste technology for selective surface functionalization and coating or for clean eumelanin particle production.


2001 ◽  
Vol 711 ◽  
Author(s):  
Yunying Wu ◽  
Yasushi Inoue ◽  
Hiroyuki Sugimura ◽  
Osamu Takai

ABSTRACTOne of the most common methods for obtaining water repellent surfaces is spreading fluoropolymer or fluoroalkylsilane onto substrates. However, this method is not applicable to low heat-resistant substrates such as plastics, since after spreading, the method requires a heating process which is generally conducted at a temperature of about 600K. The objective of this study is the preparation of ultra water-repellent and optically transparent thin films at low temperatures below 373K. The films were deposited by means of microwave plasma enhanced plasma chemical vapor deposition (MPECVD) using organosilane, that is, trimethylmethoxysilane (TMMOS) as a source with adding Ar, CO2, N2, O2 or air as an excitation gas. Under optimized preparation conditions, films with water contact angles more than 150 degrees and optical transparencies more than 90% were successfully fabricated.


Coatings ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 352 ◽  
Author(s):  
Luigi Calabrese ◽  
Amani Khaskhoussi ◽  
Salvatore Patane ◽  
Edoardo Proverbio

Superhydrophobicity is one of the most required surface properties for a wide range of application such as self-cleaning, anti-corrosion, oil-water separation, anti-icing, and anti-bioadhesion. Recently, several methods have been developed to produce nature inspired super-hydrophobic surfaces. Nevertheless, these methods require a complicated process and expensive equipment. In order to overcome these issues, we propose three different methods to obtain nature-inspired super-hydrophobic surfaces: short-term treatment with boiling water, HF/HCl and HNO3/HCl concentrated solution etching. Afterwards, a thin layer of octadecylsilane was applied by in situ polymerization on all pre-treated surfaces. Eventually, all substrates were dried for 3 h at 100 °C to complete the silane curing. Scanning electron microscopy (SEM), contact angle measuring system and atomic force microscope (AFM) were used to characterize the surfaces. Surface morphology analysis showed that each method results in a specific dual hierarchical nano-/micro-structure. The corresponding water contact angles ranged from 160° to nearly 180°. The best results were observed for HF etched Al 6082 surface were water contact angle above 175° was achieved. Furthermore, a scheme able to assess the relationship between hydrophobic behavior and surface morphology was finally proposed.


2017 ◽  
Vol 751 ◽  
pp. 137-142
Author(s):  
S.Tipawan Khlayboonme ◽  
Warawoot Thowladda

TiO2 thin films coated on glass substrates for self-cleaning applications were prepared by sol-gel dip-coating technique. The influence of annealing temperature and air exposure time on wettability was investigated by a water contact-angle measurement. Thermal annealing at temperatures of 100, 200 and 300 °C in air were conducted to the films. Surface morphology of the films was observed by FE-SEM. Elemental distribution and optical properties were examined by EDX mapping and UV-Vis transmission spectroscopy, respectively. Atomic bonding was confirmed by FTIR. The contact angle reached a maximum when the films were annealed at 200 °C. The contact angles of the as-synthesized films were 61.4±2.7°. During storage in air for 20 days, the contact angles increased to 143.1±2.1°. The films were further reannealed with 100 °C for 20 min, the contact angles were enhanced to 153.1±1.3°. The association of contact angle among the surface morphology, elemental distribution and atomic bonding of the films will be discussed.


2017 ◽  
Vol 9 (5) ◽  
pp. 05016-1-05016-5 ◽  
Author(s):  
Y. P. Saliy ◽  
◽  
L. I. Nykyruy ◽  
R. S. Yavorskyi ◽  
S. Adamiak ◽  
...  

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