scholarly journals The Adverse Effects of TiO2 Photocatalycity on Paraloid B72 Hybrid Stone Relics Protective Coating Aging Behaviors under UV Irradiation

Polymers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 262
Author(s):  
Wenjuan Li ◽  
Junling Lin ◽  
Yaru Zhao ◽  
Zihe Pan
Keyword(s):  
Contact Angle ◽  
Adverse Effects ◽  
Tio2 Nanoparticles ◽  
Water Contact Angle ◽  
Uv Irradiation ◽  
Protective Coating ◽  
Irradiation Time ◽  
Polymer Coatings ◽  
Angle Measurement ◽  
Water Contact

The incorporation of photocatalytic nanomaterials into polymer coatings is used to protect stone relics from weathering. However, the photocatalytic nanomaterials might generate excess free radicals to degrade the polymer matrix. In this work, a certain amount of TiO2 nanoparticles were dispersed into Paraloid B72 and applied onto sandstone relics to explore the adverse effects of TiO2 nanoparticles on Paraloid B72 under ultraviolet (UV) irradiation. To fulfill this goal, the effects of TiO2 on pore formation and the structure of Paraloid B72 was studied by scanning electron microscopy (SEM). Moreover, the surface chemical composition, pore structure, surface roughness and surface wettability were explored via Fourier transform infrared (FTIR) spectroscopy, SEM, optical profilometer and water contact angle measurement under UV irradiation. Results showed that the incorporation of TiO2 nanoparticles prohibited the generation of pores in Paraloid B72 and there were no pores formed when the content of TiO2 exceeded 0.8 wt%. The water contact angle of origin Paraloid B72 and TiO2/Paraloid B72 decreased with the prolonging UV irradiation. Moreover, TiO2 nanoparticles were extracted from the matrix and the pores cannot be detected with the prolonging UV irradiation time under a higher content of TiO2. These research findings might promote the understanding of using photocatalytic nanomaterials in developing stone relics’ protective coating.

scholarly journals Influence of Annealing and UV Irradiation on Hydrophilicity of Ag- Nanostructured Thin Films

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Fanming Meng ◽  
Zhaoqi Sun ◽  
Xueping Song
Keyword(s):  
Crystal Structure ◽  
Thin Films ◽  
Contact Angle ◽  
Water Contact Angle ◽  
Uv Irradiation ◽  
Annealing Time ◽  
Irradiation Time ◽  
Ambient Air ◽  
Water Contact ◽  
Nanostructured Thin Films

Ag-TiO2nanostructured thin films with silver content of 5 vol% have been deposited on silicon, glass, and quartz substrates by RF magnetron sputtering and annealed in ambient air at 900°C for 15, 30, 60, 90, and 120 min. Their crystal structure, surface morphology, and hydrophilicity have been characterized by X-ray diffractometer, atomic force microscope, and water contact angle apparatus, respectively. The influence of annealing time and UV irradiation time on hydrophilic property of Ag-TiO2thin films have been studied in detail. It is shown that annealing time influences crystal structure of Ag-TiO2thin films. The unannealed film is amorphous and shows poor hydrophilicity. With the increase of annealing time from 15 to 120 min, the grain-size slowly increases and tends to uniformity. A suitable annealing time can significantly enhance the hydrophilic behavior of Ag-TiO2films. Water contact angle decreases with the increase of irradiation time. The mechanism of hydrophilicity has been proposed and can be attributed to the increase of oxygen anion radicals and reactive center of surface .

Picoliter Water Contact Angle Measurement on Polymers

Langmuir ◽  
2007 ◽  
Vol 23 (13) ◽  
pp. 6875-6878 ◽  
Author(s):  
Michael Taylor ◽  
Andrew J. Urquhart ◽  
Mischa Zelzer ◽  
Martyn C. Davies ◽  
Morgan R. Alexander
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Water Contact ◽  
Water Contact Angle Measurement

Photocrosslinked PVDF-based star polymer coatings: an all-in-one alternative to PVDF/PMMA blends for outdoor applications

2017 ◽  
Vol 8 (20) ◽  
pp. 3045-3049 ◽  
Author(s):  
Gérald Lopez ◽  
Marc Guerre ◽  
Bruno Améduri ◽  
Jean-Pierre Habas ◽  
Vincent Ladmiral
Keyword(s):  
Contact Angle ◽  
Surface Energy ◽  
Metal Surface ◽  
Water Contact Angle ◽  
Polymer Coatings ◽  
Star Polymer ◽  
Water Contact ◽  
Adhesion Properties ◽  
Pmma Blends

A 4-arm PVDF photocrosslinked coating displays outstanding adhesion properties to a metal surface, and tunable surface energy and water contact angle.

Contact Angle Analysis on Glass Based Surface

2014 ◽  
Vol 680 ◽  
pp. 93-96
Author(s):  
Muhammad Hafiz Ab Aziz ◽  
Zaliman Sauli ◽  
Vithyacharan Retnasamy ◽  
Wan Mokhdzani Wan Norhaimi ◽  
Steven Taniselass ◽  
...  
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Hydrophobic Surface ◽  
Soda Lime ◽  
Sample Surface ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Anodic Bonding ◽  
Soda Lime Glass ◽  
Water Contact

This paper reports on the contact angle measurement analysis on a glass based surface for anodic bonding process cleaned by three distinct cleaning processes. The three types of glass based surface used were silica, pyrex, and soda lime glass. The three cleaning solutions tested in this experiment were RCA, piranha and acetone. Water Droplet Test (WDT) was done to analyze the contact angle of micro droplet on sample surface. It can be done by dropping a droplet of water in constant volume at the fixed height and angle. Only RCA process constantly decreases the contact angle value after cleaning. The compilations of data strongly proved that all samples become hydrophilic after RCA cleaning process. The solid surface is considered hydrophilic when water contact angle is smaller than 90°, and hydrophobic profile if the water contact angle is larger than 90°. Samples which undergo piranha and acetone cleaning did not prove any characteristic of hydrophilic or hydrophobic surface after cleaning.

Preparation and Characterization of Plasma-Treated Porous Poly(glycerol sebacate) Scaffolds

2013 ◽  
Vol 747 ◽  
pp. 182-185
Author(s):  
Tharinee Theerathanagorn ◽  
Boonlom Thavornyutikarn ◽  
Wanida Janvikul
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Photoelectron Spectroscopy ◽  
Average Molecular Weight ◽  
Sebacic Acid ◽  
Angle Measurement ◽  
Porous Scaffolds ◽  
Hydroxyl Groups ◽  
Condensation Polymerization ◽  
Water Contact

In this study, poly (glycerol sebacate) (PGS) was initially synthesized via condensation polymerization of glycerol and sebacic acid at equimolar ratio (1:1) at 130°C for 24 h. The number average molecular weight (Mn) of the resulting polymer determined by gel permeation chromatography (GPC) was about 2800 g/mol. Porous PGS scaffolds were subsequently prepared by a particle-leaching technique. NaCl was added into the polymer at 60-90% w/w; the mixtures were cured in Teflon molds at 140°C for 16 h. The porous scaffolds were further subjected to surface treatment with low pressure oxygen plasma to increase surface carboxyl and hydroxyl groups and thereby enhance hydrophilicity of PGS scaffold surface. The surface morphology and wettability of both untreated PGS and plasma-treated PGS scaffolds were comparatively determined by scanning electron microscopy (SEM) and water contact angle measurement, respectively. A considerable decrease in water contact angle was observed on the PGS scaffolds after the plasma treatment. The surface chemistry, mechanical strength and degree of swelling of the PGS scaffolds were also assessed by X-ray photoelectron spectroscopy (XPS), dynamic mechanical analysis (DMA) and swelling measurement, respectively.

Fabrication of superhydrophobic cotton fabrics through wrapping silica with plasma-induced grafting polymerization

2017 ◽  
Vol 89 (3) ◽  
pp. 401-410 ◽  
Author(s):  
Yongqiang Li ◽  
Chao Zou ◽  
Jianzhong Shao ◽  
Ya’nan Li
Keyword(s):  
Contact Angle ◽  
Water Contact Angle ◽  
Cotton Fabric ◽  
Photoelectron Spectroscopy ◽  
Contact Angle Measurement ◽  
Cotton Fabrics ◽  
Angle Measurement ◽  
Water Contact ◽  
Washing Durability ◽  
Before And After

Cotton fabric is commonly used in daily life, but it is easily wetted and contaminated by liquid. Herein, we present a simple and environmentally friendly plasma technology for hydrophobic modification of cotton fabric. In order to endow superhydrophobicity to cotton fabric, helium plasma inducing graft polymerization of 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane (D4Vi) was utilized to wrap SiO2 particles on cotton fabrics. Cotton fabrics were successively dipped in silica sol and D4Vi, then treated by plasma. Cotton fabrics before and after modification were characterized by using field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and water contact angle measurement. The experimental results showed that the cotton-SiO2-D4Vi consisted of nanoscale SiO2 protrusions and low-surface-energy film polymerized by D4Vi. In addition, the one wrapped SiO2 of 161 nm presented excellent hydrophobicity, washing durability, and repellency toward different types of liquids with a water contact angle of 152°.

Surface Modification of Natural Rubber Latex Film Using Photocrosslinkable Chitosan

2012 ◽  
Vol 482-484 ◽  
pp. 824-829
Author(s):  
He Ping Yu ◽  
Zong Qiang Zeng ◽  
Hong Chao Liu ◽  
Yong Yue Luo
Keyword(s):  
Contact Angle ◽  
Natural Rubber ◽  
Water Contact Angle ◽  
Irradiation Time ◽  
Natural Rubber Latex ◽  
Water Soluble ◽  
Latex Film ◽  
Latex Films ◽  
Rubber Latex ◽  
Water Contact

Surface modifications of natural rubber latex films were carried out to improve the hydrophilicity by UV-induced immobilization of water-soluble butyryl derivative of chitosan using the photosensitive hetero-bifunctional crosslinking reagent, 4-azidobenzoic acid. The effects of the concentration of modified chitosan solution and UV irradiation time on the water contact angle values of natural rubber latex films were studied. ATR-FTIR analyses confirmed that the O-butylrylchitosan molecules were covalently bonded onto the surface of natural rubber latex film. The water contact angle value of natural rubber latex film which is about 95o reduces to 55o significantly with the introduction of O-butylrylchitosan. The results indicate that the hydrophilic behaviour of natural rubber latex film has been improved by immobilization of O-butylrylchitosan.

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