Plasma treatment of heat treated beech wood – investigation on surface free energy

Holzforschung ◽  
2008 ◽  
Vol 62 (4) ◽  
Author(s):  
Arndt Wolkenhauer ◽  
Georg Avramidis ◽  
Holger Militz ◽  
Wolfgang Viöl
1993 ◽  
Vol 42 (4) ◽  
pp. 249-254 ◽  
Author(s):  
R. Cueff ◽  
G. Baud ◽  
J. P. Besse ◽  
M. Jacquet ◽  
M. Benmalek

2016 ◽  
Vol 27 (1) ◽  
pp. 41-45 ◽  
Author(s):  
Maíra do Prado ◽  
Rafael Nigri Roizenblit ◽  
Laura Villela Pacheco ◽  
Carlos Augusto de Melo Barbosa ◽  
Carolina Oliveira de Lima ◽  
...  

Abstract The aim of this study was to evaluate the effect of argon plasma on dentin surface after use of 6% NaOCl. Sixty bovine incisors had their crowns removed, the roots split, and the segments planed. One hundred twenty segments of the cervical third were used. The samples were divided in two groups (n=60): Control group: immersed in 6% NaOCl, washed, dried and then immersed in 17% EDTA, washed and dried and Argon group: after treatment described for the Control group, non-thermal argon plasma was applied for 30 s. Ten samples were evaluated by scanning electron microscopy in each group. Other ten samples were analyzed by Fourier transform infrared spectroscopy (FTIR). Thirty samples were analyzed with a goniometer to measure the contact angle between the dentin surfaces and solutions, to determine the surface free energy. The last ten samples were used to evaluate the wettability of AH Plus sealer. Data were statistically analyzed using Kruskal Wallis and Mann-Whitney tests (p<0.05). The results of this study showed that argon plasma did not modify the surface topography. FTIR analysis showed chemical modifications after plasma treatment. Argon plasma increased the surface free energy of dentin and AH Plus wettability. In conclusion, argon plasma treatment modified chemically the dentin surface. This treatment increased the surface free energy and wettability of an epoxy resin root canal sealer, favoring its bonding to dentin surfaces.


Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3476
Author(s):  
Alicja Nejman ◽  
Irena Kamińska ◽  
Izabela Jasińska ◽  
Grzegorz Celichowski ◽  
Małgorzata Cieślak

The aim of the study was to modify the surface free energy (SFE) of meta- (mAr) and para-aramid (pAr) yarns by their activation in low-pressure air radio frequency (RF) (40 kHz) plasma and assessment of its impact on the properties of the yarns. After 10 and 90 min of activation, the SFE value increased, respectively, by 14% and 37% for mAr, and by 10% and 37% for pAr. The value of the polar component increased, respectively by 22% and 57% for mAr and 20% and 62% for pAr. The value of the dispersion component for mAr and pAr increased respectively by 9% and 25%. The weight loss decreased from 49% to 46% for mAr and 62% to 50% for pAr after 90 min of activation. After 90 min, the specific strength for mAr did not change and for pAr it decreased by 40%. For both yarns, the 10 min activation in plasma is sufficient to prepare their surface for planned nanomodification.


2008 ◽  
Vol 58 ◽  
pp. 41-46 ◽  
Author(s):  
Qing Guo Tang ◽  
Jin Sheng Liang ◽  
Jun Ping Meng ◽  
Fei Wang ◽  
Li Wei Li ◽  
...  

Mineral attapulgite powders were heat treated at different temperature from 100°C to 800°C. The effect of heat treatment on properties of attapulgite were studied by particle size distribution, surface free energy, and water vapor adsorption performance. The results show that the medium particle size and surface free energy of attapulgite increase and hygroscopic capacity promptly reduce with the increase of heat temperature .The medium particle size of the raw palygorskite is 3.09 μm, and it becomes 14.12 μm after heat treatment at 800 °C. The surface free energy, polarity component and dispersion component of the natural attapulgite are 45.16mN•m-1, 13.92mN•m-1, 31.24mN•m-1, respectively, and they become 116.22 mN•m-1,116.22 mN•m-1,0.0 mN•m-1 after heat treatment at 800°C. Moreover, the hygroscopic capacity of attapulgite in 24h decreases from 17.1 % to 5.6% after heat treatment at 800°C.


2007 ◽  
Vol 14 (04) ◽  
pp. 849-852 ◽  
Author(s):  
BO-IN NOH ◽  
SEUNG-BOO JUNG

The plasma treatment on SiO 2 substrate surfaces increased the oxygen-containing functional groups or the polar component of the surface free energy and, the wetting characteristics of the underfills/ SiO 2. The plasma treatment condition which gave the smallest contact angle between the underfills and SiO 2 was an operating time of 60 sec under O 2 gas atmosphere and a power of 200 W.


2012 ◽  
Vol 02 (02) ◽  
pp. 132-136 ◽  
Author(s):  
S. M. Pelagade ◽  
N. L. Singh ◽  
R. S. Rane ◽  
S. Mukherjee ◽  
U. P. Deshpande ◽  
...  

Coatings ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 228 ◽  
Author(s):  
Essam Abdel–Fattah

The atmospheric pressure of Ar + H 2 O plasma jet has been analyzed and its effects on the poly(methyl methacrylate) (PMMA) surface has been investigated. The PMMA surface treatment was performed at a fixed gas flow-rate discharge voltage, while varying the plasma treatment time. The Ar + H 2 O plasma was studied with optical emission spectroscopy (OES). Optimum plasma conditions for PMMA surface treatment were determined from relative intensities of Argon, hydroxyl radical (OH), oxygen (O) I emission spectra. The rotational temperature T rot of Ar + H 2 O plasma was determined from OH emission band. The PMMA surfaces before and after plasma treatment were characterized by contact angle and surface free energy measurements, X-ray photoelectrons spectroscopy (XPS), atomic force microscope (AFM) and UV-spectroscopy. The contact angle decreased and surface free energy increased with plasma treatment time. XPS results revealed the oxygen to carbon ratio (O/C) on plasma-treated PMMA surfaces remarkably increased for short treatment time ≤60 s, beyond which it has weakly dependent on treatment time. The carbon C1s peak deconvoluted into four components: C–C, C–C=O, C–O–C and O–C=O bonds and their percentage ratio vary in accordance with plasma treatment time. AFM showed the PMMA surface roughness increases with plasma treatment time. UV-visible measurements revealed that plasma treatment has no considerable effect on the transparency of PMMA samples.


Sign in / Sign up

Export Citation Format

Share Document