Pickering-Type Emulsions of ODSA Sizing Agent Stabilized by Nano-Montmorillonite and N-Dodecane

2013 ◽  
Vol 319 ◽  
pp. 233-238 ◽  
Author(s):  
De Hai Yu ◽  
Zhao Yun Lin ◽  
You Ming Li

Octadecenylsuccinic anhydride (ODSA) is an internal sizing agent used to hydrophobize paper and paper board in the process of papermaking. Nano-montmorillonite (MMT) particles and n-dodecane were used as the stabilizer to prepare stable ODSA Pickering emulsions. The effects of pH value, particle concentration, hydrolysis resistance and paper sizing performance of the ODSA Pickering emulsions were investigated. It was found that the stability of ODSA emulsions first increased and then decreased as the pH value decreased. More stable oil-in-water (o/w) emulsion can be made using 10 vol.% n-dodecane. Particle concentration was linked to the formation of particle films at oil–water interface, with a required minimum particle concentration of 1.5 wt.%. Paper sizing degree analysis indicated that the ODSA Pickering emulsions show increased hydrolysis resistance and good sizing performance.

RSC Advances ◽  
2015 ◽  
Vol 5 (110) ◽  
pp. 90651-90658 ◽  
Author(s):  
Cuige Zhang ◽  
Ye Zhu ◽  
Rongli Zhang ◽  
Yanling Xie ◽  
Kangjing Wang ◽  
...  

Novel composite nanoparticles were prepared from lysozyme and modified poly (γ-glutamic acid) to be used as emulsifiers for Pickering emulsions. Increasing the pH value of the solution facilitated the formation of gel-like emulsions suitable for releasing lysozyme.


Polymers ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1071 ◽  
Author(s):  
Yu-Jin Cho ◽  
Dong-Min Kim ◽  
In-Ho Song ◽  
Ju-Young Choi ◽  
Seung-Won Jin ◽  
...  

A pyromellitic dianhydride (PMDA) and 4,4′-oxydianiline (ODA)-based oligoimide (PMDA-ODA) was synthesized by a one-step procedure using water as a solvent. The PMDA-ODA particles showed excellent partial wetting properties and were stably dispersed in both water and oil phases. A stable dispersion was not obtained with comparison PMDA-ODA particles that were synthesized by a conventional two-step method using an organic solvent. Both oil-in-water and water-in-oil Pickering emulsions were prepared using the oligoimide particles synthesized in water, and the size of the emulsion droplet was controlled based on the oligoimide particle concentration. The oligoimide particles were tested to prepare Pickering emulsions using various kinds of oils. The oil-in-water Pickering emulsions were successfully applied to prepare microcapsules of the emulsion droplets. Our new Pickering emulsion stabilizer has the advantages of easy synthesis, no need for surface modification, and the capability of stabilizing both oil-in-water and water-in-oil emulsions.


Fluids ◽  
2019 ◽  
Vol 4 (4) ◽  
pp. 186 ◽  
Author(s):  
Rajinder Pal

Suspensions and emulsions are prone to kinetic instabilities of sedimentation and creaming, wherein the suspended particles and droplets fall or rise through a matrix fluid. It is important to understand and quantify sedimentation and creaming in such dispersed systems as they affect the shelf-life of products manufactured in the form of suspensions and emulsions. In this article, the unhindered and hindered settling/creaming behaviors of conventional emulsions and suspensions are first reviewed briefly. The available experimental data on settling/creaming of concentrated emulsions and suspensions are interpreted in terms of the drift flux theory. Modeling and simulation of nanoparticle-stabilized Pickering emulsions are carried out next. The presence of nanoparticles at the oil/water interface has a strong influence on the creaming/sedimentation behaviors of single droplets and swarm of droplets. Simulation results clearly demonstrate the strong influence of three-phase contact angle of nanoparticles present at the oil/water interface. This is the first definitive study dealing with modeling and simulation of unhindered and hindered creaming and sedimentation behaviors of nanoparticle-stabilized Pickering emulsions.


2015 ◽  
Vol 11 ◽  
pp. 2355-2364 ◽  
Author(s):  
Shintaro Kawano ◽  
Toshiyuki Kida ◽  
Mitsuru Akashi ◽  
Hirofumi Sato ◽  
Motohiro Shizuma ◽  
...  

Background: Emulsions stabilized by colloidal particles are known as Pickering emulsions. To date, soft microgel particles as well as inorganic and organic particles have been utilized as Pickering emulsifiers. Although cyclodextrin (CD) works as an attractive emulsion stabilizer through the formation of a CD–oil complex at the oil–water interface, a high concentration of CD is normally required. Our research focuses on an effective Pickering emulsifier based on a soft colloidal CD polymer (CD nanogel) with a unique surface-active property. Results: CD nanogels were prepared by crosslinking heptakis(2,6-di-O-methyl)-β-cyclodextrin with phenyl diisocyanate and subsequent immersion of the resulting polymer in water. A dynamic light scattering study shows that primary CD nanogels with 30–50 nm diameter assemble into larger CD nanogels with 120 nm diameter by an increase in the concentration of CD nanogel from 0.01 to 0.1 wt %. The CD nanogel has a surface-active property at the air–water interface, which reduces the surface tension of water. The CD nanogel works as an effective Pickering emulsion stabilizer even at a low concentration (0.1 wt %), forming stable oil-in-water emulsions through interfacial adsorption by the CD nanogels. Conclusion: Soft CD nanogel particles adsorb at the oil–water interface with an effective coverage by forming a strong interconnected network and form a stable Pickering emulsion. The adsorption property of CD nanogels on the droplet surface has great potential to become new microcapsule building blocks with porous surfaces. These microcapsules may act as stimuli-responsive nanocarriers and nanocontainers.


Author(s):  
Deepak Khurana ◽  
Sudhakar Subudhi

Abstract The present paper deals with the forced convection of Al2O3/water and TiO2/water nanofluids with the variation of pH and addition of surfactant in nanofluids. The aim of this study is to investigate the effect of suspension stability on the heat transfer and pressure drop characteristics of nanofluids. The present experimental set up is same as used by our earlier paper [1]. The suspension stability of nanofluids is improved by varying pH of nanofluids. The pH in this study is varied from 3.5±0.2 to 12.5±0.2. Addition of surfactants is employed to improve the suspension stability of nanofluids. The SDS (sodium dodecyl sulfate) surfactant of 0.05 wt % is used to increase the stability of nanofluids in the present study. It is observed that by increasing the suspension stability with the variation of pH and addition of surfactant, the heat transfer characteristics have improved appreciably. The maximum enhancement in heat transfer is obtained with TiO2/water nanofluids at a particle concentration of 0.1 vol % and a pH of 3.5±0.2.


Adsorption ◽  
2019 ◽  
Vol 25 (4) ◽  
pp. 903-911
Author(s):  
Jolanta Narkiewicz-Michalek ◽  
Marta Szymula ◽  
Sonia Losada-Barreiro ◽  
Carlos Bravo-Diaz

2019 ◽  
Vol 10 (9) ◽  
pp. 5498-5509 ◽  
Author(s):  
Andrea Araiza-Calahorra ◽  
Anwesha Sarkar

The aim of this study was to restrict the degree of gastric destabilization of Pickering emulsions by using electrostatic deposition of a biopolymeric layer at the proteinaceous particle–laden oil–water interface.


Sign in / Sign up

Export Citation Format

Share Document