scholarly journals Effect of Sanding Processes on the Surface Properties of Modified Poplar Coated by Primer Compared with Mahogany

Coatings ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 856 ◽  
Author(s):  
Qingqing Liu ◽  
Di Gao ◽  
Wei Xu
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Surface Treatment ◽  
Surface Properties ◽  
Equilibrium Contact Angle ◽  
Density Parameter ◽  
Distilled Water ◽  
Poplar Wood ◽  
Surface Pretreatment ◽  
Average Spacing

The surface roughness, static and dynamic liquid wettability of modified poplar wood were measured by different surface treatment of brushing primer and sanding. With the increase of the number of grinding paper, the depth parameters Ra, Ry, Rz and Rp of surface roughness of modified poplar decreased, and the density parameter Sm (the average spacing of micro unevenness of contour) decreased at first and then increased. With the increase of number of the grinding paper, the contact angle of water and glycerol for modified poplar wood decreased at first and then increased. After the modified poplar wood was brushed with the primer and sanded with 240# sandpaper, the density parameter Sm was 0.307, the equilibrium contact angle of distilled water was 34.88, and the equilibrium contact angle of glycerin was 36.46, all of which were the lowest number. At this time, the surface roughness was improved, and the modified poplar has the good wettability that is greater than the mahogany wood wettability. Compared with mahogany, the rough depth parameters of the modified poplar are smaller to those of mahogany, but the Sm of modified poplar wood is greater than that of the mahogany. After the same surface pretreatment, the wetting speed of glycerol on the surface of mahogany is higher than that of the modified poplar.

SURFACE MODIFICATION OF TPR SOLE: AN APPROACH TO IMPROVE SLIP RESISTANCE ON QUARRY AND CERAMIC TILES

2015 ◽  
Vol 88 (1) ◽  
pp. 163-175 ◽  
Author(s):  
R. Mohan ◽  
S. Raja ◽  
G. Saraswathy ◽  
B. N. Das
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Surface Modification ◽  
Surface Treatment ◽  
Coefficient Of Friction ◽  
Chemical Surface ◽  
Resistance Property ◽  
Slip Resistance ◽  
The Coefficient Of Friction ◽  
Trichloroisocyanuric Acid

ABSTRACT Human slip on smooth surfaces is a common accident, even though the footwear soling materials are designed with cleats and treads to provide more friction with the floor. About 20% of footwear is made with thermoplastic rubber (TPR; styrene-butadiene-styrene) soles. The slip resistance property under wet-flooring conditions of this kind of sole is poor because of the nonionic nature of the polymer. Chemical surface modification can be exploited to improve the slip-resistance property of TPR soles. The surface is chemically modified with trichloroisocyanuric acid in a methyl ethyl ketone medium (TCI/MEK; at 1, 2, and 3%) to introduce chlorinated and oxidized moieties to the rubber surface. The extent of surface modification produced in TPR with this change can be tested using attenuated total reflectance–Fourier transform infrared spectroscopy, scanning electron microscopy, and contact angle and surface roughness measurements. The improvement in slip resistance can be evaluated by measuring the coefficient of friction using a dynamic slip-resistance tester. The extent of the change in the functional physical properties, such as surface roughness, contact angle, work adhesion, in slip resistance can be improved by optimizing the concentration of trichloroisocyanuric acid. Physicomechanical properties of unmodified and modified soles that are essential for wear performance can be tested and compared. Quantitative changes on the surface of modified rubber soles increases surface roughness, reduces contact angles, and increases work energy, so there is a considerable increase in the coefficient of friction, especially under wet floor conditions. The chemical surface treatment tends to reduce the bulk mechanical properties, such as tensile strength, elongation at break, and abrasion resistance, because cyanuric acid attacks the sole. The coefficient of friction produces a positive trend at 1 and 2% TCI/MEK treatments, but the trend is negative at a 3% concentration. The optimum surface treatment level for surface modification to enhance the slip resistance of TPR is 2% TCI/MEK.

The Effect of Drop Volume on Contact Angle

1991 ◽  
Vol 54 (3) ◽  
pp. 232-235 ◽  
Author(s):  
JOSEPH MCGUIRE ◽  
JIANGUO YANG
Keyword(s):  
Contact Angle ◽  
Surface Properties ◽  
Solid Surface ◽  
Contact Surface ◽  
Contact Angles ◽  
Equilibrium Contact Angle ◽  
Drop Volume ◽  
Food Contact ◽  
Food Contact Surface ◽  
Limiting Value

The effect of drop volume on the equilibrium contact angle, used in evaluation of food contact surface properties, was measured for liquids exhibiting both polar and nonpolar character on six different materials. Drop volumes used ranged from 2 to 40 μl. Contact angles were observed to increase with increasing drop volume in a range below some limiting value, identified as the critical drop volume (CDV). The CDV varied among materials and is explained with reference to surface energetic heterogeneities exhibited by each type of solid surface.

WETTING OF ROUGH SURFACES

2004 ◽  
Vol 11 (01) ◽  
pp. 7-13 ◽  
Author(s):  
XINPING ZHANG ◽  
SIRONG YU ◽  
ZHENMING HE ◽  
YAOXIN MIAO
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Sessile Drop ◽  
Test Sample ◽  
Contact Angles ◽  
Sessile Drop Method ◽  
Equilibrium Contact Angle ◽  
Roughness Surface ◽  
Solid Substrates ◽  
Effect Of Surface

This paper focuses on effects of roughness on wettability. According to Wenzel's equation, the transition of theoretical wetting contact angles is 90°, whereas many experimental results have indicated that such a transition takes place at contact angles smaller than 90°. A new model of wetting on roughness surface is established in this paper. The model indicates that the influencing factors of wetting on roughness surface include not only equilibrium contact angle θ0 and surface roughness, but also the system of liquids and solid substrates. There is a corresponding transition angle for every surface roughness, and the transition angle is lower than 90°. Surface roughness is propitious to improve the contact angle only when θ0 is lower than the transition angle. The effect of surface roughness on the contact angle increases with the increase of rE. To engineer the surface with different roughnesses, a Ti test sample is polished with sandpaper with abrasive number 350, 500, 1000 and 2000; the contact angles of water on Ti are measured by the sessile drop method. The results of the theoretical analysis agree with experimental ones.

scholarly journals Surface properties of poplar wood after heat treatment, resin impregnation, or both modifications

BioResources ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. 7562-7577
Author(s):  
Shuai Cao ◽  
Jiabin Cai ◽  
Meihui Wu ◽  
Nan Zhou ◽  
Zhenhua Huang ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Surface Roughness ◽  
Surface Properties ◽  
Urea Formaldehyde ◽  
Formaldehyde Resin ◽  
Poplar Wood ◽  
Resin Impregnation ◽  
Heat Treated ◽  
Populus Tomentosa Carr ◽  
Heat Treatment Sample

To investigate the surface properties of different modified poplar (Populus tomentosa Carr.) wood samples, the color, surface roughness, and wettability of untreated poplar wood (control) and poplar modified via heat treatment, resin impregnation, and impregnation combined heat treatment were analyzed and compared in this study. The impregnant used in the test was a modified urea-formaldehyde resin with a low molecular weight and low viscosity. The results showed that the lightness of the samples was sorted in order as follows: the control was lighter than the resin impregnated sample, which was lighter than the impregnation combined heat treatment sample, which was lighter than the heat treatment sample. The surface of the control samples was relatively smooth, while after the impregnation, heat, and impregnation combined heat treatments, the Ra and Rz values increased, which indicated increased surface roughness due to the modifications. Among them, the heat-treated samples had the roughest surface, and the surface roughness of the impregnation combined heat treated samples at 160 °C had no major difference from the resin impregnated sample. The wettability of the samples decreased after heat treatment and increased after impregnation combined heat treatment. It was concluded that after the modification treatments, the color of the wood became darker, and the surface roughness and hydrophobicity increased.

The Wetting of Insect Cuticles by Water

1955 ◽  
Vol 32 (3) ◽  
pp. 591-617 ◽  
Author(s):  
M. W. HOLDGATE
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Surface Properties ◽  
Surface Composition ◽  
Contact Angles ◽  
Aquatic Species ◽  
Water Contact ◽  
Calliphora Erythrocephala ◽  
Wetting Properties ◽  
Wide Range

1. The water contact angles of insects show a wide range of variation, which is broadly correlated with surface roughness and with habitat. 2. The contact angles of species inhabiting stored products or carrion are greatly modified by contamination. This produces large variations between apparently similar individuals. 3. In terrestrial insects surface roughness increases the contact angles to very large apparent values. Detailed analyses of its effect have been made in the pupa of Tenebrio molitor and the adult Calliphora erythrocephala. In some aquatic insects surface roughness leads to a reduction in the contact angles; this has been studied in the nymph of Anax imperator. 4. Prolonged immersion in water causes a lowering of the contact angles of all the insects examined, and the low angles of many aquatic species may therefore be the direct effect of their environment. In some aquatic species there is evidence of the active maintenance of a large contact angle during life. 5. Changes in contact angle accompany processes of cuticle secretion and will occur at any moult if changes in roughness or habitat take place. 6. The observed variations of surface properties can be explained without assuming any variation in the chemical composition of the cuticle surface. Wetting properties are of little value as indicators of cuticle surface composition. 7. The biological aspects of insect surface properties are briefly discussed.

scholarly journals Mechanical and Surface Properties of Resilient Denture Liners Modified with Chitosan Salts

Materials ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 3518
Author(s):  
Maike Herla ◽  
Klaus Boening ◽  
Heike Meissner ◽  
Katarzyna Walczak
Keyword(s):  
Mechanical Properties ◽  
Surface Roughness ◽  
Statistical Analysis ◽  
Surface Properties ◽  
Control Group ◽  
Distilled Water ◽  
Denture Stomatitis ◽  
Antifungal Properties ◽  
Denture Liners ◽  
Antibacterial And Antifungal

Chitosan (CS) and its derivatives show antibacterial and antifungal properties and could help treat and prevent denture stomatitis (DS). Mechanical and surface properties of resilient denture liners were evaluated when modified with CS salts. CS-hydrochloride (CS-HCl) and CS-glutamate (CS-G) were added to resilient denture liners Ufi Gel P and Coe-Soft at four different concentrations (0.1%, 0.2%, 0.4%, 1% w/w) from which specimens were produced, as well as a control group of each material with no added CS salt. Ten specimens per group (Ø 35 mm, height 6 mm) were manufactured. They were stored in distilled water at 37 °C for a total of 30 days (d). Shore A hardness (SHA) and surface roughness (Ra) were evaluated after 24 h (T1), 7 d (T2), 14 d (T3) and 30 d (T4). Kruskal–Wallis and U-test (Bonferroni-Holm adjusted) were used for statistical analysis (p ≤ 0.05). Ra increased significantly once CS salts were added. SHA increased significantly for some groups, but all specimens fulfilled requirements set by ISO 10139-2:2016. Modification with CS salts does not influence the mechanical properties of the modified resilient denture liners in a clinically relevant manner. Despite the increased roughness, the concept is suitable for further studies. Especially antimicrobial/antibiofilm studies are needed.

The effect of CH4/H2 ratio on the surface properties of HDPE treated by CHx ion beam bombardment

2016 ◽  
Vol 30 (17) ◽  
pp. 1650214 ◽  
Author(s):  
Wanyu Ding ◽  
Yuanyuan Guo ◽  
Dongying Ju ◽  
Susumu Sato ◽  
Teruo Tsunoda
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Surface Properties ◽  
Chemical Bond ◽  
High Density Polyethylene ◽  
Ion Beam ◽  
High Density ◽  
Static Contact Angle ◽  
Structures And Properties ◽  
Static Contact

The surface of high density polyethylene (HDPE) substrate was bombarded by the CH[Formula: see text] group ion beam, which was generated by the mixture of CH4/H2. Varying the CH4/H2 ratio, HDPE surfaces with different chemical bond structures and properties were obtained. Raman and XPS results show that [Formula: see text] and [Formula: see text] bond structures are formed at HDPE surface bombarded by CH[Formula: see text] group ions. The [Formula: see text] bond fraction at bombarded HDPE surface depends on the H2 ratio in CH4/H2 mixture, because the H ion/atom/molecule can improve the growth of [Formula: see text] bond structure. For HDPE surface bombarded by CH4/H2 = 50/50, [Formula: see text] bond fraction reaches the maximum of 30.5%, the surface roughness decreases to 17.04 nm, and the static contact angle of polar H2O molecule increased to 140.2[Formula: see text].

Surface Treatment in Solar Cell Technology

1968 ◽  
Vol 26 ◽  
pp. 216-217
Author(s):  
J. C. Evans ◽  
K. M. Evans
Keyword(s):  
Thin Film ◽  
Surface Roughness ◽  
Electron Microscope ◽  
Solar Cell ◽  
Surface Treatment ◽  
Light Trapping ◽  
Decisive Role ◽  
Distilled Water ◽  
Time Period ◽  
Solar Cell Technology

In the fabrication of solar cells of both the crystalline and thin film types, surface treatment has been found to play a decisive role. The electron microscope has been used in an attempt to isolate and to optimize those surface features which contribute beneficially towards increased cell performance. From our work thus far it is suspected that surface roughness plays a significant role in the efficiency of light-trapping so basic to this form of energy conversion device. We have observed that etchants used to prepare the semiconductor surfaces often attack these surfaces quite selectively, producing identifiable surfaces determined by the etchant used and the semiconductor so treated. For example, an etch of a cadmium sulfide vacuum evaporated film with hydrochloric acid, one part in three parts of distilled water produced an etch less harsh or rough as a similar dilution of phosphoric acid in the same time period.

Surface Roughness Effect on the Solid Equilibrium Contact Angle

2017 ◽  
Vol 17 (6) ◽  
pp. 4271-4274 ◽  
Author(s):  
In-Hye Kim ◽  
Kyo-Han Kim ◽  
Jun Sik Son ◽  
Tae-Yub Kwon
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Equilibrium Contact Angle ◽  
Roughness Effect

scholarly journals Examining Parameters of Surface Quality Performance of Paulownia Wood Materials Modified by Thermal Compression Technique

2021 ◽  
Vol 72 (3) ◽  
pp. 231-236
Author(s):  
Zeki Candan ◽  
Oktay Gonultas ◽  
Hizir Volkan Gorgun ◽  
Oner Unsal
Keyword(s):  
Surface Roughness ◽  
Contact Angle ◽  
Surface Properties ◽  
Color Change ◽  
Solid Wood ◽  
Control Group ◽  
Compression Process ◽  
Compression Technique ◽  
Thermal Compression ◽  
Color Properties

The aim of this study was to evaluate the effect of thermal compression process on some surface properties of paulownia solid wood materials. The widest surface of wood samples was mechanically compressed at high temperatures. The duration was 45 min. Four different process combinations were created, including two temperatures (150 °C and 170 °C) and two pressure levels (20 bar and 22.5 bar). The surface roughness, wettability and color properties of treated and untreated samples were compared. The roughness properties, both parallel and perpendicular to grain direction, were determined according to JIS B 0601:1994 standard. The contact angle changes of water dripped to the surface were measured according to time. For color properties, a spectrophotometer was used according to CIE L*a*b* system. The color changes were classified according to a grading method from literature. The most remarkable results on wettability were observed. The contact angle values significantly increased with this method. Although higher temperature increased the contact angle values, higher pressures did not change the values. When the surface roughness values were generally considered, this technique could decrease the values up to 40 % ratio according to the control group. Only the combination of 150 °C and 20 bar did not significantly change the values. Lastly, the results of color properties showed that all treatment parameters significantly affected total color change values of samples. Grading results were similar and the color change of modified samples graded as the lowest color difference, except with the combination of 150 °C and 20 bar. The combination of 170 °C and 22.5 bar (highest treatment conditions) significantly changed all color characteristics of samples, except b* parameter. The results of this research showed that mechanical thermal compression method could change surface properties of this fast-growing species.

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