Archive for the ‘Hot Article’ Category

Stable Liquid Drop Deformation with Nanoparticles

Miniature reaction vessels, such as liquid marbles, have shown significant promise for millimeter scale and low volume chemical and biological experiments. Here, solid particles are trapped at the drop surface, separating the interior liquid from the surface, so the droplet does not stick to the substrate. For large scale applications, liquid marbles have some handicaps, including their lack of optical clarity and their restriction to only a spherical shape. In a recent full article in Soft Matter, a collaborative research team has recently discovered a liquid marble alternative, where nanoparticles are squeezed onto a drop surface to alter its shape while still maintaining optical transparency and reaction vessel properties.

Water drops and liquid plasticine deformed with nanoparticles

Deformed water drops and examples of liquid plasticine.

To create the stable deformation of a liquid, a single water drop is placed between two glass surfaces. The two glass surfaces were coated with layers of hydrophobic silica nanoparticles. When the drop was squeezed between the two modified glass layers and then released, nanoparticles detached from the glass and became adhered at the water droplet surface. Once the squeezing force was released and as the droplet tried to recover to its original spherical shape, the new nanoparticle layers on the drop surface became “jammed”, and permanently deformed the water droplet shape. The final shape of the deformed droplet was determined by the squeezing force, but the shape of the droplet could be adjusted by injecting new water into the drop, breaking apart the surface nanoparticles.

Moving from single water drops to larger volumes and exploiting the jamming properties of the nanoparticles, liquid plasticines could be developed. The water was deformed into a variety of shapes and used as small reaction vessels. Multiple plasticines were joined for controlled chemical reactions and then quickly separated using a hydrophobic knife. As proof of concept, a liquid plasticine with gold nanoparticles was connected to DC power (30 V) allowing the gold nanoparticles to migrate to the positive end of the plasticine. The liquid was then cut to separate the gold particles from the rest of the liquid. The permanently deformed drops and liquid plasticines offer new alternatives for liquid lenses and small volume liquid reactors.

See the full Soft Matter article here:

Liquid plasticine: controlled deformation and recovery of droplets with interfacial nanoparticle jamming

Xiaoguang Li, Yahui Xue, Pengyu Lv, Hao Lin, Feng Du, Yueyun Hu, Jun Shen, and Huiling Duan



Morgan M. StantonDr. Morgan M. Stanton is currently a postdoctoral researcher at the Max Planck Institute for Intelligent Systems in Stuttgart, Germany. She completed her Ph.D. in Chemistry from Worcester Polytechnic Institute in 2014. Read more about Morgan’s research publications here or you can follow her on Twitter @morg368.

Follow the latest Soft Matter publications and updates on Twitter @softmatter or on Facebook.

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Modeling boron nitride nanopores for DNA sequence detection

Quickly detecting DNA sequences with high accuracy is a significant goal for diagnostic medicine and genetics. The vast quantities of DNA and its small size make it difficult to achieve this goal. Nanopores offer a rapid method of detection by threading strands of DNA through a nanopore to detect individual nucleotides of the DNA. Solid-state nanopores separate two fluidic chambers and as the DNA passes through the pore, the pore becomes partially clogged and produces a blockage of ionic currents. The change in ionic current can be used to collect structural information from the DNA. Graphene has been well studied, experimentally and theoretically, for fabrication of these pores, but graphene produces significant complications with DNA detection. Graphene pores often contain material defects and DNA sticks to graphene, blocking the pores permanently, limiting detection capabilities. In a recent full article in Soft Matter, a collaborative research team tackles this issue by theoretically modeling DNA in a boron-nitride

Boron-nitride nanopore for double stranded DNA detection using molecular dynamics

Boron-nitride nanopore for double stranded DNA detection

Boron-nitride is composed of boron and nitride atoms in a honeycomb structure. The material is just as thin as graphene and exhibits similar desirable electrical and mechanical properties, but is more resistive to DNA adhesion, allowing the DNA to pass through the pore without permanent blockage. The research group used large-scale molecular dynamics to model double stranded DNA passing through boron-nitride pores ranging in size from 2.5 to 6.5 nm with an external voltage of 1.0 V. The smaller 2.5 nm pore size had greater blockage currents and a higher sensitivity to DNA threading through the pore than the larger pores due to its smaller cross-sectional area. Double stranded DNA composed of only adenine-thymine (A-T) or guanine-cytosine (G-C) nucleotide pairs were compared using the 2.5 nm pores with multiple applied voltages with the goal of understating the changes is current signal as the DNA passed through the pore. The greatest difference between A-T DNA and G-C DNA was observed at 1.0 V with G-C DNA exhibiting greater stretching and stress than the A-T DNA. Both sets of DNA passed readily through the boron-nitride nanopores without permanent blockage. In comparison, in modelling of DNA passing through graphene nanopores, DNA exhibited significant adhesion and breakage of the DNA at the pore. The large changes is current signal between A-T and G-C DNA and the lack of DNA adhesion using boron-nitride pores offer an exciting opportunity for future DNA sequencing. The molecular dynamic modeling presented will hopefully influence current experimental work in the development of DNA detection with nanopores.

See the full Soft Matter article here:

DNA translocation through single-layer boron nitride nanopores
Zonglin Gu, Yuanzhao Zhang, Binquan Luan and Ruhong Zhou
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Morgan M. Stanton

Dr. Morgan M. Stanton is currently a postdoctoral researcher at the Max Planck Institute for Intelligent Systems in Stuttgart, Germany. She completed her Ph.D. in Chemistry from Worcester Polytechnic Institute in 2014. Read more about Morgan’s research publications here or you can follow her on Twitter @morg368.

Follow the latest Soft Matter publications and updates on Twitter @softmatter or on Facebook

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Bacteria motors guided by liquid crystals

Bacteria play a vital role in digestive, reproductive, and immune health within the human body.  Recently, motile bacteria have been analyzed for their ability to transport cargo in confined environments.  Bacteria convert surrounding chemical energy into mechanical work making them ideal for a micro scale motor.  Although bacteria have proven capable of transporting cargo, directing where they swim and understanding how they interact with the cargo has been a challenge.   A research group from University of Wisconsin-Madison, USA has utilized nematic liquid crystals to guide bacteria swimming and monitor how they associate with their cargo load. The full work is described in a recent communication article in Soft Matter.

P. mirabillis cell pushes a C. albicans cell

A motile P. mirabilis cell pushes a non-motile C. albicans cell

The motile bacteria, P. mirabilis, were used to push non-motile fungal cells, C. albicans, in a directed path.  Both the bacterial and fungal cells are found in patients with urinary tract infections.  The urinary epithelium secretes layers of mucus within the urinary tract which is guided by external flow; molecules and cells in the urinary tract exhibit directional alignment due to the mucus flow.  The proposed nematic liquid crystal environment with motile and non-motile cells represents a simple model of the human urinary tract.  The alignment of the liquid crystal guides the bacteria and causes them to swim along the director field, similar to cells in the urinary epithelium.  P. mirabilis were mixed with C. albicans and suspended within a 20 µm thick liquid crystal layer composed of disodium cromoglycate.  Single P. mirabilis cells pushed the non-motile C. albicans cells along the director of the liquid crystal, to give straight or curved swimming tracks depending on the crystal orientation.  The P. mirabilis were capable of reaching a velocity of 1 – 2 µm/s-1 while transporting their fungal cell cargo.

For a greater understanding of the cargo transport mechanism, 2 µm diameter beads were mixed with the P. mirabilis. Bacteria transporting beads were capable of reaching velocities of 5 µm/s-1.  The hydrodynamics of the system of swimming bacteria and particles was analyzed with the mathematical model, regularized Stokeslets.  The observed experimental swimming velocity correlated with numerical simulated results, with a clear trend of decreasing speed with increasing cargo size.  The mathematical model suggests hydrodynamic interaction of the bacteria flagella and cargo load are an important for predicting system velocity.  The work helps understand cellular interspecies interaction that is controlled with liquid crystal alignment.

See the full Soft Matter communication here:

Bacterial transport of colloids in liquid crystalline environments
Rishi R. Trivedi, Rina Maeda, Nicholas L. Abbott, Saverio E. Spagnolie, and Douglas B. Weibel
Soft Matter, Advanced Article, 2015
DOI: 10.1039/C5SM02041G


Morgan M. Stanton

Dr. Morgan M. Stanton is currently a postdoctoral researcher at the Max Planck Institute for Intelligent Systems in Stuttgart, Germany.  She completed her Ph.D. in Chemistry from Worcester Polytechnic Institute in 2014.  Read more about Morgan’s research publications here or you can follow her on Twitter @morg368.

Follow the latest Soft Matter publications and updates on Twitter @softmatter or on Facebook

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Hydrogel capable of protein release using red light

Hydrogel synthesis is a well-established method of incorporating cells, proteins, or drugs into a biocompatible polymer network.  The majority of hydrogels are stimulated and cross-linked by a chemical reaction or UV light, but this can limit their use in vivo as these methods damage healthy cells. Using red light-stimulated hydrogels would be better suited for the therapeutic use of hydrogels, as it creates little photo damage to cells and red light can penetrate deeper into tissue than other light wavelengths. Such a hydrogel was developed by a research group at the Max Planck Institute for Polymer Research in Germany and is described in detail in a recently published full article in Soft Matter. The group describes a synthetic method of hydrogel formation using methoxy-modified azobenzene that activates the polymer complex under red light.

azobenzene trans-to-cis transition with β-cyclodextrin using red light

The hydrogel synthesis is based on the spontaneous formation of a supramolecular complex by combining an azobenzene (mAzo) derivative and β-cyclodextrin (β-CD).  The two chemical species were individually grafted onto a poly(acrylic acid) (PAA) polymer backbone and mixed to form the red light-activated hydrogel.  During exposure to red light, the azobenzene moiety in mAzo underwent isomerization from the trans to cis state, which was not hindered by the presence of β-CD.  The process is reversible, with heat or blue light returning mAzo to the trans state.  While the mAzo polymer remained in the trans state, the mAzo/β-CD complex maintained a gelatin formation, but once altered to the cis state by red light, the hydrogel destabilized and became a liquid.  This sol-to-gel transition is explained by the high binding constant between trans mAzo and β-CD (Ka = 1546 M-1) compared to low binding constant between cis mAzo and β-CD (Ka = 82.1 M-1).

To demonstrate the hydrogel’s utility for medical applications, the hydrogel was loaded with the protein, bovine serum albumin (BSA).  Exposure to red light dissolved the hydrogel and released ~83% of the protein into solution.  If a piece of porcine tissue was placed between the red light source and the protein laden hydrogel, mAzo was still capable of transitioning to the cis state for disassembly of the gel and release of the BSA.  The ability of the hydrogel to be activated through tissue using non-invasive and non-detrimental red light is an impressive step for the development of therapeutic and light-stimulated polymers for controlled drug or protein release.

See the full Soft Matter article here:

Supramolecular hydrogels constructed by red-light-responsive host–guest interactions for photo-controlled protein release in deep tissue
Dongsheng Wang, Manfred Wagner, Hans-Jürgen Butt, and  Si Wu
Soft Matter, 2015, Advance Article
DOI: 10.1039/C5SM01888A


Morgan M. StantonDr. Morgan M. Stanton is currently a postdoctoral researcher at the Max Planck Institute for Intelligent Systems in Stuttgart, Germany.  She completed her Ph.D. in Chemistry from Worcester Polytechnic Institute in 2014.  Read more about Morgan’s research publications here or you can follow her on Twitter @morg368.

Follow the latest Soft Matter publications and updates on Twitter @softmatter or on Facebook


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A simple method for preventing nanoparticle-protein aggregation

The interaction of proteins with nanoparticles has significant applications for clinical and biomedical therapies, specifically the field of theranostics, where diagnostic and therapeutic agents are combined into a single entity.  Unfortunately, it has been well documented that attachment of proteins to nanoparticle surfaces leads to deformation of the protein and loss of protein activity.  Aggregates of proteins form on the particle and induce aggregate formation of the particles themselves, hindering any theranostic capability.

In a recent communication in Soft Matter, researchers from Johns Hopkins University, USA, and Jawaharlal Nehru Centre for Advanced Scientific Research, India, describe a simple chemical method for solving this dilemma; addition of sugar.  The naturally occurring disaccharide, trehalose, has demonstrated the ability to stabilize protein structures and shield them from thermal stress and dehydration.  The protective nature of trehalose has been described by three hypotheses: (1) mechanical entrapment of the protein within the sugar molecules, (2) hydrogen bonding of the trehalose with the protein for chemical stabilization, (3) or water entrapment between the surface of the protein and trehalose.  The research team exploited the protective properties of trehalose to insulate the protein, lysozyme, while the protein was exposed to silver nanoparticles, thus preventing denaturing of the protein.

Silver nanoparticles

Interaction of silver nanoparticles with lysozyme with varying trehalose concentrations

Without chemical stabilization, lysozyme aggregated on the nanoparticle surface and had significant structural deorganization.  In the presence of trehalose, lysozyme maintained its active conformation and exhibited limited or no aggregation.  By adjusting the concentration of trehalose in solution, nanoparticle-protein interactions were modulated.  Analytical methods, including UV-vis absorbance, circular dichroism, and surface enhanced Raman spectroscopy (SERS) illustrated and characterized the changes is binding of the lysozyme to the silver nanoparticle surface and the enhanced stability of the protein.  The proof-of-concept system created a biocompatible environment for nanoparticles and proteins to engage without compromising lysozyme structure or activity.  The proposed method will facilitate the development of nanoparticle theranostics and opens new avenues for nanomedicine design.

See the full Soft Matter article here:

Revealing the trehalose mediated inhibition of protein aggregation through lysozyme-silver nanoparticle interaction
Soumik Siddhanta, Ishan Barman, and Chandrabhas Narayana
Soft Matter, 2015, Advance Article
DOI: 10.1039/C5SM01896J


Morgan M. Stanton Dr. Morgan M. Stanton is currently a postdoctoral researcher at the Max Planck Institute for Intelligent Systems in Stuttgart, Germany.  She completed her Ph.D. in Chemistry from Worcester Polytechnic Institute in 2014.  Read more about Morgan’s research publications here.

Follow the latest Soft Matter publications and updates on Twitter @softmatter or on Facebook

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HOT Articles for June!

Imaging viscoelastic properties of live cells by AFM: power-law rheology on the nanoscale
Fabian M. Hecht, Johannes Rheinlaender, Nicolas Schierbaum, Wolfgang H. Goldmann, Ben Fabry and Tilman E. Schäffer

Graphical abstract: Imaging viscoelastic properties of live cells by AFM: power-law rheology on the nanoscale

Studying the concentration dependence of the aggregation number of a micellar model system by SANS
Matthias Amann, Lutz Willner, Jörg Stellbrink, Aurel Radulescu and Dieter Richter

Graphical abstract: Studying the concentration dependence of the aggregation number of a micellar model system by SANS

These articles will be free until 29th June 2015


Transverse migration of polyelectrolytes in microfluidic channels induced by combined shear and electric fields
Mert Arca, Jason E. Butler and Anthony J. C. Ladd

Graphical abstract: Transverse migration of polyelectrolytes in microfluidic channels induced by combined shear and electric fields

Cholesterol expels ibuprofen from the hydrophobic membrane core and stabilizes lamellar phases in lipid membranes containing ibuprofen
Richard J. Alsop, Clare L. Armstrong, Amna Maqbool, Laura Toppozini, Hannah Dies and Maikel C. Rheinstädter

Graphical abstract: Cholesterol expels ibuprofen from the hydrophobic membrane core and stabilizes lamellar phases in lipid membranes containing ibuprofen

These articles will be free until 8th June 2015


Modelling the rheology of anisotropic particles adsorbed on a two-dimensional fluid interface
Alan M. Luo, Leonard M. C. Sagis, Hans Christian Öttinger, Cristiano De Michele and Patrick Ilg

Graphical abstract: Modelling the rheology of anisotropic particles adsorbed on a two-dimensional fluid interface

Nonthermal fluctuations of the mitotic spindle
Kevin Smith, Brian Griffin, Henry Byrd, F. C. MacKintosh and Maria L. Kilfoil

Graphical abstract: Nonthermal fluctuations of the mitotic spindle

These articles will be free until 13th July 2015


Fluctuations of particle motion in granular avalanches – from the microscopic to the macroscopic scales
Ziwei Wang and Jie Zhang

Graphical abstract: Fluctuations of particle motion in granular avalanches – from the microscopic to the macroscopic scales
A giant polymer lattice in a polymer-stabilized blue phase liquid crystal
H. Kikuchi, S. Izena, H. Higuchi, Y. Okumura and K. Higashiguchi 

Graphical abstract: A giant polymer lattice in a polymer-stabilized blue phase liquid crystal

These articles will be free until 21st  July 2015



pH-Responsive assembly of metal nanoparticles and fluorescent dyes by diblock copolymer micelles
Hyun Woo Kim, Jang Whan Kim, Seong Ho Jo, Chang-Lyoul Lee, Won-Ki Lee, Seong Soo Park, Bonghoon Chung and Seong Il Yoo

Graphical abstract: pH-Responsive assembly of metal nanoparticles and fluorescent dyes by diblock copolymer micelles



Two types of Cassie-to-Wenzel wetting transitions on superhydrophobic surfaces during drop impact
Choongyeop Lee, Youngsuk Nam, Henri Lastakowski, Janet I. Hur, Seungwon Shin, Anne-Laure Biance, Christophe Pirat, Chang-Jin “CJ” Kim and Christophe Ybert 

Graphical abstract: Two types of Cassie-to-Wenzel wetting transitions on superhydrophobic surfaces during drop impact

These articles will be free until 27th  July 2015


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HOT Articles for May!

A new lattice Monte Carlo simulation for dielectric saturation in ion-containing liquids
Xiaozheng Duan and Issei Nakamura

Graphical abstract: A new lattice Monte Carlo simulation for dielectric saturation in ion-containing liquids

Domain walls and anchoring transitions mimicking nematic biaxiality in the oxadiazole bent-core liquid crystal C7
Young-Ki Kim, Greta Cukrov, Jie Xiang, Sung-Tae Shin and Oleg D. Lavrentovich

Graphical abstract: Domain walls and anchoring transitions mimicking nematic biaxiality in the oxadiazole bent-core liquid crystal C7

These articles will be free until 3rd June 2015


Interface-enforced complexation between copolymer blocks
Alexander A. Steinschulte, Weinan Xu, Fabian Draber, Pascal Hebbeker, Andre Jung, Dimitri Bogdanovski, Stefanie Schneider, Vladimir V. Tsukruk and Felix A. Plamper

Graphical abstract: Interface-enforced complexation between copolymer blocks

A dynamic and self-crosslinked polysaccharide hydrogel with autonomous self-healing ability
Fuyuan Ding, Shuping Wu, Shishuai Wang, Yuan Xiong, Yan Li, Bin Li, Hongbing Deng, Yumin Du, Ling Xiao and Xiaowen Shi

Graphical abstract: A dynamic and self-crosslinked polysaccharide hydrogel with autonomous self-healing ability

These articles will be free until 8th June 2015


Surfactant-induced assembly of enzymatically-stable peptide hydrogels
Brad H. Jones, Alina M. Martinez, Jill S. Wheeler and Erik D. Spoerke  

Graphical abstract: Surfactant-induced assembly of enzymatically-stable peptide hydrogels

Tunable synthesis of self-assembled cyclic peptide nanotubes and nanoparticles
Leming Sun, Zhen Fan, Yongzhong Wang, Yujian Huang, Michael Schmidt and Mingjun Zhang

Graphical abstract: Tunable synthesis of self-assembled cyclic peptide nanotubes and nanoparticles
 

These articles will be free until 16th  June 2015


Anisotropic colloidal transport and periodic stick-slip motion in cholesteric finger textures
Kui Chen, Linnea P. Metcalf, David P. Rivas, Daniel H. Reich and Robert L. Leheny

Graphical abstract: Anisotropic colloidal transport and periodic stick-slip motion in cholesteric finger textures
 

Heterogeneous flow kinematics of cellulose nanofibril suspensions under shear
F. Martoïa, C. Perge, P. J. J. Dumont, L. Orgéas, M. A. Fardin, S. Manneville and M. N. Belgacem

Graphical abstract: Heterogeneous flow kinematics of cellulose nanofibril suspensions under shear

These articles will be free until 23rd  June 2015


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HOT Articles for April!

In situ laser-imprinted surface realignment of a nematic liquid crystal
Giorgio Mirri, Miha Škarabot and Igor Muševič

Graphical abstract: In situ laser-imprinted surface realignment of a nematic liquid crystal

Electrostatic swelling of bicontinuous cubic lipid phases
Arwen I. I. Tyler, Hanna M. G. Barriga, Edward S. Parsons, Nicola L. C. McCarthy, Oscar Ces, Robert V. Law, John M. Seddon and Nicholas J. Brooks

Graphical abstract: Electrostatic swelling of bicontinuous cubic lipid phases

These articles will be free until 28th  April 2015


Self-assembly of mesogenic bent-core DNA nanoduplexes
Khanh Thuy Nguyen, Anna Battisti, Daniele Ancora, Francesco Sciortino and Cristiano De Michele

Graphical abstract: Self-assembly of mesogenic bent-core DNA nanoduplexes

Self-assembly of microcapsules regulated via the repressilator signaling network
Henry Shum, Victor V. Yashin and Anna C. Balazs

Graphical abstract: Self-assembly of microcapsules regulated via the repressilator signaling network

These articles will be free until 22nd May 2015


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HOT Articles for March!

Phase separation in ternary fluid mixtures: a molecular dynamics study
Awaneesh Singh and Sanjay Puri

Graphical abstract: Phase separation in ternary fluid mixtures: a molecular dynamics study

Phase transformations in binary colloidal monolayers
Ye Yang, Lin Fu, Catherine Marcoux, Joshua E. S. Socolar, Patrick Charbonneau and Benjamin B. Yellen 

Graphical abstract: Phase transformations in binary colloidal monolayers
These articles will be free until 30th March 2015


Spider’s super-glue: thread anchors are composite adhesives with synergistic hierarchical organization
Jonas O. Wolff, Ingo Grawe, Marina Wirth, André Karstedt and Stanislav N. Gorb

Graphical abstract: Spider's super-glue: thread anchors are composite adhesives with synergistic hierarchical organization

Stretching self-entangled DNA molecules in elongational fields
C. Benjamin Renner and Patrick S. Doyle

Graphical abstract: Stretching self-entangled DNA molecules in elongational fields

These articles will be free until 6th April 2015


Smectic block copolymer thin films on corrugated substrates
Aldo D. Pezzutti, Leopoldo R. Gómez and Daniel A. Vega

Graphical abstract: Smectic block copolymer thin films on corrugated substrates

Solving the mystery of the internal structure of casein micelles
B. Ingham, G. D. Erlangga, A. Smialowska, N. M. Kirby, C. Wang, L. Matia-Merino, R. G. Haverkamp and A. J. Carr

Graphical abstract: Solving the mystery of the internal structure of casein micelles

These articles will be free until 6th April 2015


Flexibility and protection by design: imbricated hybrid microstructures of bio-inspired armor
Stephan Rudykh, Christine Ortiz and Mary C. Boyce

Graphical abstract: Flexibility and protection by design: imbricated hybrid microstructures of bio-inspired armor

Derivation of stretched exponential tap density equations of granular powders
Tian Hao

Graphical abstract: Derivation of stretched exponential tap density equations of granular powders

These articles will be free until 21st  May 2015


Mechanism of anomalously increased oil displacement with aqueous viscoelastic polymer solutions
Andrew Clarke, Andrew M. Howe, Jonathan Mitchell, John Staniland, Laurence Hawkes and Katherine Leeper

Self-assembly of Janus particles under shear
Arash Nikoubashman, Emanuela Bianchi and Athanassios Z. Panagiotopoulos

These articles will be free until 25th  May 2015


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Building Next-Generation Superplasticisers from Plant-Derived Lignin

Superplasticisers are a class of materials used to inhibit aggregation in hydraulic cement, improving workability and reducing water requirements without sacrificing strength. Most superplasticisers are anionic polymer dispersants, such as the leading commercial products, polycarboxylate ethers. A low-cost alternative to this class of materials is provided by the plant-derived biopolymer lignin. Lignin is an abundant biopolymer as it is found in most land plants as a component in cell walls. However, Lignin-based substances are poorly performing plasticisers and attempts to significantly improve their properties by copolymerisation with synthetic monomers have thus far been relatively unsuccessful.

In this recent report Gupta et al. provide an alternate approach to the production of high-performance superplasticisers by utilising lignin as a macroinitiator for a reverse addition-fragmentation chain-transfer (RAFT) polymerisation. RAFT is a controlled radical polymerisation technique, which affords good control of molecular weight and polydispersity. Acrylamide was polymerised from the lignin surface in order to create grafted architectures composed of lignin cores with synthetic polyacrylamide coronas. It is found that the lignin compounds synthesised using RAFT polymerisation are more efficient superplasticisers than those prepared by free radical polymerisation, due to their unique polymer-grafted architecture.

The resulting lignin based materials reduced the yield stress of cement paste to similar levels as a leading commercial superplasticiser at concentrations ten-fold lower. These compounds have excellent potential as next-generation admixtures for hydraulic cement, with further work needed to clarify optimal grafting density and length of coronal polymer-chains.

Comparison of physical properties of cement with different superplasticizers
Comparison of physical properties of cement with different superplasticisers

To findout more read the full article below:

Molecular Architecture Requirements for Polymer-Grafted Lignin Superplasticizers by Chetali Gupta, Madeline J. Sverdlove and Newell R. Washburn, Soft Matter, 2015, Advance Article. DOI: 10.1039/C4SM02675F

This post was written by web writer Rob Woodward. Rob is currently based in Imperial College London working in the Polymer and Composite Engineering (PaCE) group. Rob has a background in both responsive polymeric surfactants and microporous organic polymers for carbon capture and storage.

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