Modification of food contacting surfaces by plasma polymerisation technique. Part I: Determination of hydrophilicity, hydrophobicity and surface free energy by contact angle method

The purpose of this research was to determine surface free energy and contact angle of hydrolyzed shellac by using sessile drop technique. It is a method for determination of contact angle by placing a drop of liquid on a substrate and the surface free energy is then calculated by using the Wus equation. The substrate in this study was the hydrolyzed shellac prepared by hydrolysis of the native shellac at various times; 0, 15, 30 and 45 min using 2.0 %w/w sodium hydroxide. Water, formamide and ethylene glycol were liquids used for the investigation of the contact angle and surface free energy. The effect of hydrolysis time tended to reduce the contact angle and increase in the total surface free energy and polar force of hydrolyzed shellac. The result could be due to the breaking of the ester bonds of shellac during the hydrolysis process causing the higher free carboxyl group giving the higher polar group indicating by higher polar force and surface free energy. Therefore, the contact angle and surface free energy detected by sessile drop technique could be of benefit for the determination of hydrolysis process.

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Static solvent contact angle measurements, surface free energy and wettability determination of various self-assembled monolayers on silicon dioxide

Thin Solid Films ◽

10.1016/j.tsf.2006.04.006 ◽

2006 ◽

Vol 515 (4) ◽

pp. 1433-1438 ◽

Cited By ~ 290

Author(s):

Dimitri Janssen ◽

Randy De Palma ◽

Stijn Verlaak ◽

Paul Heremans ◽

Wim Dehaen

Keyword(s):

Contact Angle ◽

Free Energy ◽

Silicon Dioxide ◽

Surface Free Energy ◽

Self Assembled Monolayers ◽

Angle Measurements ◽

Contact Angle Measurements ◽

Assembled Monolayers ◽

Self Assembled

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Determination of the specific surface free energy of natural quartz crystals using measurement of contact angle of liquid droplets

Crystal Research and Technology ◽

10.1002/crat.201000308 ◽

2010 ◽

Vol 45 (12) ◽

pp. 1305-1308 ◽

Cited By ~ 6

Author(s):

T. Suzuki ◽

H. Kasahara

Keyword(s):

Contact Angle ◽

Free Energy ◽

Specific Surface ◽

Surface Free Energy ◽

Liquid Droplets ◽

Natural Quartz ◽

Quartz Crystals

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Some problems of characterization of a solid surface via the surface free energy changes

Adsorption Science & Technology ◽

10.1177/0263617417704115 ◽

2017 ◽

Vol 35 (7-8) ◽

pp. 647-659 ◽

Cited By ~ 4

Author(s):

Emil Chibowski

Keyword(s):

Contact Angle ◽

Free Energy ◽

Experimental Determination ◽

Surface Free Energy ◽

Solid Surface ◽

Contact Angles ◽

Absolute Value ◽

Receding Contact

During the processes occurring at a solid surface, the changes in the surface free energy take place. The knowledge about surface free energy is very helpful for understanding the processes taking place on the surface. However, experimental determination of solid surface free energy is still not a fully solved problem. In this paper, some problems dealing with calculation of solid surface free energy from contact angle are discussed based on literature values of advancing and receding contact angles measured on four different fluoropolymers surface. The four approaches most often used for the calculation are described and especial focus on the approach in which both the advancing and receding contact angles is paid. It is concluded that using probing liquids the absolute value of solid surface free energy cannot be determined. However, the determined apparent values of the energy are very helpful to understand the conditions necessary for a given process to occur.

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