Characterization and evaluation of the surface free energy for cementitious materials

Dong, Biqin; Yang, Lve; Yuan, Quan; Liu, Yuqing; Zhang, Jianchao; Fang, Guohao; Wang, Yanshuai; Yan, Yinghuan; Xing, Feng

doi:10.1016/j.conbuildmat.2015.12.143

Cited by 12 publications

(13 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, the testing process of the sessile drop method is greatly affected by temperature and humidity, leading to inaccurate measurement of contact angles [ 20 , 21 , 22 , 23 , 24 , 25 ]. The bubble method, by contrast, is insensitive to environmental disturbance [ 26 , 27 , 28 ], and was adopted herein to measure the contact angle of the geopolymer. Contact angles and surface properties of geopolymers were tested using an optical contacting angle instrument (OCA 20 model, manufactured by Data Physics Instruments, Filderstadt, Germany).…”

Section: Methodsmentioning

confidence: 99%

“…A bubble of air or alkane was then released from a needle at a speed of 0.6 microliters per second, which was operated via the injection system of OCA instrument. Eleven types of alkane were used to produce the air bubbles; their chemical compositions and surface free energies are listed in [ 28 ]. Since the density of the chosen alkanes was lower than that of the water, the bubbles were well-formed and tightly attached to the test surface under the action of buoyancy.…”

Section: Methodsmentioning

confidence: 99%

“…As an important indicator of wetting degree in a solid–liquid system, the work of adhesion is related to the surface energy of two contacted phases [ 28 , 31 ]:

where W a is the work of adhesion, γ 1 and γ 2 are the surface energy of phase 1 and 2, respectively, and γ 12 is the interfacial energy between phase 1 and phase 2.…”

Section: Methodsmentioning

confidence: 99%

“…Surface energy is the action resulting from different molecular forces, among which the dispersion force and polarity force are the most important [ 25 , 28 ]. Therefore, the total surface energy and work of adhesion can be divided into a dispersion-force component and a polarity-force component [ 25 , 26 , 28 , 32 , 33 ]:

where γ is the total surface energy, γ d and γ p are the dispersive-force and polarity-force components and W a d and W a p are the work of adhesion contributed by the dispersion force and polarity force between molecules.…”

Section: Methodsmentioning

confidence: 99%

“…Four different surface modifiers were also mixed in or applied on top of the geopolymer coating. The surface energy of the geopolymer was calculated based on the derivation of Thomas Young’s three-phase solid–liquid–gas equilibrium equation [ 26 , 27 , 28 ]. Moreover, the critical surface energy of geopolymers was obtained for geopolymer coatings in the water of different polar partial ratios, which can be utilized for predicting the wetting feature of a specific liquid on the surface of the geopolymer.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Green Protective Geopolymer Coatings: Interface Characterization, Modification and Life-Cycle Analysis

et al. 2022

Self Cite

View full text Add to dashboard Cite

In the interest of solving the resource and environmental problems of the construction industry, low-carbon geopolymer coating ensures great durability and extends the service life of existing infrastructure. This paper presents a multidisciplinary assessment of the protective performance and environmental impacts of geopolymer coating. Various parameters, such as main substance, water-solid (W/S) ratio, activator type and curing time, were investigated for their effects on interface characterization in terms of contact angle, surface energy, mechanical properties and microstructure. These parameters had negligible effects on the amounts and types of hydrophilic functional groups of geopolymer surfaces. A combination of organic surface modifiers and geopolymer coatings was shown to ensure hydrophobic surface conditions and great durability. Silicon-based modifiers exhibited better wetting performance than capillary crystalline surfactants by eliminating hydroxyl groups and maintaining structural backbone Si-O-T (Si, Al) on geopolymers’ surfaces. Finally, life-cycle analysis was conducted to investigate the environmental performance. Geopolymer coating yielded substantially lower environmental impacts (50–80% lower in most impact categories) than ordinary Portland cement (OPC) coating. Silicon-based modifiers had negligible influence due to their minimal usage. Increasing the W/S ratio diluted the geopolymer coating and decreased the environmental impacts, and slag-based geopolymer coating achieved lower environmental impacts than FA-based and MK-based varietie.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

“…As an important indicator of wetting degree in a solid–liquid system, the work of adhesion is related to the surface energy of two contacted phases [ 28 , 31 ]:

where W a is the work of adhesion, γ 1 and γ 2 are the surface energy of phase 1 and 2, respectively, and γ 12 is the interfacial energy between phase 1 and phase 2.…”

Section: Methodsmentioning

confidence: 99%