scholarly journals Modification of Silicone Elastomers Using Silicone Comonomers Containing Hydrophilic Surface Active Endgroups

2014 ◽  
Vol 1626 ◽  
Author(s):  
Jonathan Goff ◽  
Barry Arkles ◽  
Santy Sulaiman
Keyword(s):  
Contact Angle ◽  
Mechanical Performance ◽  
Silicone Elastomer ◽  
Hydrophobic Contact ◽  
Silicone Elastomers ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Friction Measurements ◽  
Time Frames

ABSTRACTA facile technique was developed for a long-term increase in silicone elastomer surface hydrophilicity, eliminating the need for post-cure surface treatment (e.g. oxygen plasma or surface grafting). Well-defined silicones (1-4 kDa) with a central vinyl functionality and discrete PEG2, PEG3 and tetrahydrofurfuryl (THF) pendant endgroups were synthesized, characterized and used as comonomers in addition-cure, platinum catalyzed 2-part silicone elastomer formulations. The modified silicone elastomers were optically clear and maintained the mechanical performance characteristic of this class of material with up to 20 wt.% comonomer in the 2-part formulation. Contact angle measurements of deionized water on the silicone elastomer surface showed improved wettability with comonomer content. The elastomer surface shifted from hydrophobic (contact angle ∼120°C) to hydrophilic (contact angle < 90°C) at ∼5 wt.% comonomer loadings for extended time frames (> 5 months). Coefficient of friction measurements of the modified silicone elastomers revealed an increase in surface lubricity with comonomer loadings.

Vertically aligned CNT arrays: structural integrity and surface properties

2016 ◽  
Vol 7 (6) ◽  
pp. 703-711 ◽  
Author(s):  
Dimitris K. Perivoliotis ◽  
Malamatenia A. Koklioti ◽  
Elias P. Koumoulos ◽  
Yiannis S. Raptis ◽  
Costas A. Charitidis
Keyword(s):  
Contact Angle ◽  
Structural Integrity ◽  
Mechanical Performance ◽  
Content Type ◽  
Cvd Method ◽  
Angle Measurements ◽  
Hydrophobic Behavior ◽  
Static Contact ◽  
Contact Angle Measurements ◽  
Cnt Arrays

Purpose Carbon nanotube-based architectures have increased the scientific interest owning to their exceptional performance rendering them promising candidates for advanced industrial applications in the nanotechnology field. Despite individual CNTs being considered as one of the most known strong materials, much less is known about other CNT forms, such as CNT arrays, in terms of their mechanical performance. The paper aims to discuss these issues. Design/methodology/approach In this work, thermal CVD method is employed to produce VA-MWCNT carpets. Their structural properties were studied by means of SEM, XRD and Raman spectroscopy, while their hydrophobic behavior was investigated via contact angle measurements. The resistance to indentation deformation of VA-MWCNT carpets was investigated through nanoindentation technique. Findings The synthesized VA-MWCNTs carpets consisted of well-aligned MWCNTs. Static contact angle measurements were performed with water and glycerol, revealing a rather super-hydrophobic behavior. Originality/value The structural analysis, hydrophobic behavior and indentation response of VA-MWCNTs carpets synthesized via CVD method are clearly demonstrated.

Mechanical and Wettability Performance of Sand/HDPE Composite Sheets

2020 ◽  
Vol 1015 ◽  
pp. 9-14
Author(s):  
Sidra Siraj ◽  
Ali Al Marzouqi ◽  
M.Z. lqbal
Keyword(s):  
Contact Angle ◽  
Maleic Anhydride ◽  
High Density Polyethylene ◽  
Mechanical Performance ◽  
Good Alternative ◽  
Surface Wetting ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Compatibilizing Agent ◽  
Potential Use

Polymer/composite sheets were developed using sand as the filler, and high-density polyethylene (HDPE), by melting extrusion in a melt blender followed by compression molding. The effects of addition of filler, and the addition of polyethylene grafted maleic anhydride (PE-g-MA) as the compatibilizing agent were investigated by observing the morphology, the mechanical performance as well as the wettability characteristic via contact angle measurements. A decreasing trend was observed with filler addition, both for the Young’s modulus and yield stress values of each of the samples, from 1200.81 MPa and 35.15 MPa at 0 wt% to 1182.33 MPa and 23.11 MPa for the non-compatibilized sheet at 35 wt%, to 629.95 MPa and 9.56 MPa in the case of the compatibilized sheet respectively. However, addition of filler did not significantly affect the surface wetting in any case, thereby promoting good anti-wetting performance for both sets of sheets. As a result, the potential use of such synthetic composite sheets could be considered as a good alternative for applications which require reduced ductility or increased anti-wetting performance.

Wettability Determination by Equilibrium Contact Angle Measurements: Reservoir Rock- Connate Water System With Injection of CO2

2012 ◽  
Author(s):  
Narjes Shojaikaveh ◽  
Cas Berentsen ◽  
Susanne Eva Johanne Rudolph-Floter ◽  
Karl Heinz Wolf ◽  
William Richard Rossen
Keyword(s):  
Contact Angle ◽  
Water System ◽  
Reservoir Rock ◽  
Equilibrium Contact Angle ◽  
Connate Water ◽  
Angle Measurements ◽  
Contact Angle Measurements

Surface Wettability Enhances Osteoblast Adhesion on Silicon-Substituted Hydroxyapatite Thin Films

2007 ◽  
Vol 330-332 ◽  
pp. 877-880 ◽  
Author(s):  
E.S. Thian ◽  
J. Huang ◽  
Serena Best ◽  
Zoe H. Barber ◽  
William Bonfield
Keyword(s):  
Thin Films ◽  
Contact Angle ◽  
Actin Filaments ◽  
Culture Study ◽  
Cell Culture Study ◽  
Angle Measurements ◽  
Contact Angle Measurements ◽  
Osteoblast Adhesion ◽  
Lower Contact

Crystalline hydroxyapatite (HA) and 0.8 wt.% silicon-substituted HA (SiHA) thin films were produced using magnetron co-sputtering. These films were subjected to contact angle measurements and in vitro cell culture study using human osteoblast-like (HOB) cells. A wettability study showed that SiHA has a lower contact angle, and thus is more hydrophilic in nature, as compared to HA. Consequently, enhanced cell growth was observed on SiHA at all time-points. Furthermore, distinct and well-developed actin filaments could be seen within HOB cells on SiHA. Thus, this work demonstrated that the surface properties of the coating may be modified by the substitution of Si into the HA structure.

Characterization of plasma-treated poly (hydroxybutyrate) membrane surfaces by ESCA and contact angle measurements

1992 ◽  
Vol 73 (2-3) ◽  
pp. 163-172 ◽  
Author(s):  
Dietmar Flösch ◽  
Giorgio Clarotti ◽  
Kurt E. Geckeler ◽  
François Schué ◽  
Wolfgang Göpel
Keyword(s):  
Contact Angle ◽  
Membrane Surfaces ◽  
Angle Measurements ◽  
Contact Angle Measurements
Sign in / Sign up

Export Citation Format

Share Document