Adaptable hydrogels, built through dynamic covalent bonds, have recently emerged as a promising platform for tissue engineering and regenerative medicine [1,2]. The dynamic nature of the crosslinks in these polymer networks enables them to have shear-thinning (viscous flow under shear stress) and self-healing (recovery upon relaxation) characteristics. Therefore, adaptable hydrogels can be...
Proteins are known to adsorb to polylelectrolytes on the “wrong” side of the isoelectric point, i.e. when the overall charge of the protein has the same sign as that of the polyelectrolyte. This has been attributed to patchy charge distribution on the proteins, whereas changes in their ionization upon adsorption have been neglected. In this work we show that the patchy charge distribution is...
Stimuli-responsive polymers are capable of modifying their chemical/physical properties upon exposure to different stimuli (temperature, pH, ionic strength). On another hand the currently emerging development of sequence-controlled copolymerization strategies open up opportunities for the design of new generations of smart polymers [1]. Methods like iterative single addition of monomers by...
The employment of biobased polymers, specifically, those extracted from the biomass (polysaccharides such as chitosan, alginate or agarose and proteins such as gelatin) is of particular interest for the development of biomedical applications. This is motivated on the one hand by the fact that many biobased polymers are able to assemble in water in response to different stimuli (pH, temperature...
As molecular workhorses, proteins fulfill a multitude of tasks that keep the complex machinery in biological cells alive. In order to be biologically active, most soluble proteins require their surface to be covered with water. This so-called hydration water is generally acknowledged to enable a protein to undergo the internal motions that are so fundamental for its capacity to fulfill a...
Active films made of poly (butylene adipate-co-terephthalate) and a small amount of silver exchanged montmorillonite (2, 3 and 5% by weight) for food packaging use were successfully prepared via solvent casting method. PBAT/AgMMT nanocomposites containing different AgMMT loadings were characterized by several techniques. X-Ray Diffraction, UV-visible Spectroscopy and Transmission Electron...
In spite of their multifarious applications, graphene quantum dots (GQDs) necessitate surface modifications to enhance their solution processability. To alleviate the problem, we have synthesized four poly(ε-caprolactone) (PCL) functionalized GQDs (S1-S4) with different degrees of polymerization (3, 7, 15 and 21) of PCL using ring opening polymerization. The as synthesized materials show...
Copolymers are widely employed in industrial processes because their physico-chemical properties, like strength, elasticity or thermal behaviour, can be modified by varying their macromolecular composition. Poly isobornyl acrylate (PIBOA) is a commercial available polymer with many attractive, industrial qualities, including excellent transparence, low refractive index, low thermal expansion,...
Radiation curing technologies provide a number of economic advantages over the usual thermal operation like: rapid through cure, low energy requirements, room temperature treatment, non-polluting, solvent-free formulations and low costs [1]. One of its applications is the light induced polymerization which has attracted great interest. Most research work into visible light-initiated ...
The low conductivity of MoS2 presents a huge barrier for the exploitation of its supercapaciator electrode application and hydrogen evolution reaction (HER) catalyst. To alleviate this difficulty, we have synthesized MoS2 quantum dots (QDs) having greater quantity of catalytic edge sites by breaking up bulk MoS2 sheet using the solvent exfoliation technique. The synthesized MoS2 QDs are...
The technique of molecular Imprinting has undergone remarkable development over the last decades, this technology has increased tremendously in last years. The recognition capabilities of molecularly imprinted polymers (MIPs) are being successfully exploited in many application areas such as sensors, separations and extraction of chemical compounds, drug development, and drug delivery [1-3]....
Self-assembling systems comprise of materials that enable complex structures to form from molecular building blocks without external impetus. In particular, the chemical and physical properties of the self-assembled structure are encoded in the corresponding characteristics of the building blocks, thereby offering the potential for rationally designed materials with properties that are...
Solution composition is known to strongly influence the stable state of macromolecules, with important practical applications ranging from colloidal dispersions to solvated synthetic polymers or proteins. Cosolutes with different affinities to specific macromolecular states can shift equilibrium towards the thermodynamically preferred state with lower free energy. Solutes preferentially...
In the medical field and especially for cancer treatment, intensive researches are performed to deliver the drug at the right position allowing to reduce the dose and side effects. The poor solubility in biological fluids of most of the approved drugs obliges to encapsulate them into carriers. The triblock copolymers Pluronics are bio-compatible and are stealth carriers [1]. Hyaluronic acid...
We present in this talk three types of hybrid materials made up from covalent polymers and supramolecular polymers that form thermoreversible gels and therefore possess fibrillar morphology. Two main cases are shown: i) intermingled gel where the polymer gel and the organogel pervade one another [1], ii) sheathed or jacketed nanowires, where one component trigger the growth of the other by...
Hyaluronic acid (HA) is one of the most important polysaccharide in biology. It is often associated with proteins (or other molecules) by specific interactions, but also via electrostatic interactions, hydrogen bounding and hydrophobic forces. One important property of HA is that its biological function can be various depending on its molecular weight and like any biological system, its...
Nanoprecipitation is a very useful technique for encapsulation of hydrophobic species in nanoparticles dispersed in aqueous systems. In particular it enables encapsulation of a hydrophobic drug in submicron particles and thereby effectively increases its water solubility but the technique is more generally applicable in various areas of physics, medicine and chemistry. A key factor that...
Poly(N-isopropylacrylamide) (PNIPAM) is a well-known thermoresponsive polymer showing a lower critical solution temperature (LCST) of approximately 32°C in water. Below the LCST, PNIPAM is commonly believed to be well-hydrated with a Gaussian coil conformation. Above the LCST polymer-water interactions become unfavorable leading to the release of water and the well-known coil-to-globule...
The use of multicomponent solvents has provided remarkable results in biomass fractionation processes of several levels of severity. Despite all invested efforts, no fractionation method is currently capable of achieving lignocellulose deconstruction in an economically viable commercial scale process. Understanding the factors that drive to the interaction of biomass with different solvents is...
To develop new polymer materials with new properties, polymer mixtures are one of the most used methods. A mixture of two polymers may lead either to interpolymer complex or to a blend. The temperature, the solvent and the hydrophobicity of the polymers are among the most important factors that influence the formation and stability of such polymer mixtures. Proton donor poly (vinyl chloride)...
Blends and nano blends based on an organically modified bentonite, from Maghnia Algeria (OBT) (1,5 and 3 % by weight) and poly (styrene‐co‐allyl alcool) (PSAA) containing 40 mol % of allyl alcohol and of Cellulose Acetate Butyrate (CAB), were elaborated via solution intercalation method and characterized by several techniques such as Fourier transform infrared spectroscopy (FTIR) and Scanning...
Enhancing miscibility, mechanical and thermal properties of polymer blends by adding a nanofiller has received increasing attention in both scientific and industrials communities. Ternary nanoblends (PEMA/CAB/OMMT) based on cellulose acetate butyrate/ poly (ethyl methacrylate) blends, of different ratios (30/70, 50/50 and 70/30), and an organically modified bentonite (OMMT) (1, 2 and 4%) were...
At present, the water pollution is the most important problem for the environment sustainability. Among the contaminants that cause the greatest concern, there are the Contaminants of Emerging Concern (CECs). These compounds are PCBs, pesticides, herbicides, phenols, polycyclic aromatic hydrocarbons (PAHs), Persistent organic Pollutants (POPs) and Pharmaceuticals and Personal Care Products...
For the past 5 decades, small angle scattering techniques have brought considerable knowledge on polymers (melt, blends, in solution, self-assembling), and the isotopic labelling allowed by neutrons has been leveraged to offer a unique insight. With modern sources and instruments, the flux, data quality and window of observation that span from atoms to micrometers is creating new possibilities...
The Maxwell electromagnetic equations obey parity (P), however, Wu et al, first proved a clear violation of parity conservation in the beta decay of cobalt-60. [1] It is now widely believed that in physical systems having weak interactions parity violation is possible. Now the question is if it is true in physical systems why not in chemical systems, particularly where there is...
pH-sensitive interpenetrating polymer network (IPN) is a class of materials widely used in water purification and drug delivery. This study shows the elaboration of such material based on both crosslinked cellulose and poly-hydroxyl-ethyl-methacrylate (poly-HEMA) through the sequenced synthesis method. Cellulose was crosslinked by epichlorohydrin whereas the poly-hydroxy-ethyl-methacrylate is...
The present work combines the solar energy with the environmental protection through the membrane selectivity for metallic ions. Firstly, we have elaborated new polymeric membranes for ions separation. The membrane is polymerized from cellulose triacetate modified by poly-ethyleneimine and plasticized by 2-nitrophenyl pentyl ether. Different membranes are characterized by Fourier Transform...
We report on the synthesis of a silica nanoparticle (NP)-reinforced oligosiloxane nanohybrid mate-rial (SM-nanocomposite) and demonstrate its properties as a robust transparent hard coating material for various applications. The oligosiloxane (MMO) resin as a matrix was synthesized using methyl andmethacryl silanes via a hydrolytic sol-gel condensation. The silica NPs with various sizes (12,...
Self-assembling peptides gain increasing interest as scaffolds for novel bionanomaterials; rationally designed self-assembling building blocks are especially attractive. We have been focusing on modular designs that consist of a central ultrashort amphiphilic motif derived from the adenovirus fiber shaft. This central amphiphilic motif can be further modified with amino acids targeted for...
Self-Assembly is a widely occurring phenomenon in nature. Understanding the shape-determining factors is key for tailoring nanoparticles with desired structural properties. Furthermore, switchability between disassembled and the assembled state through external triggers would increase the application potential. This contribution will discuss nanoparticles consisting of positively charged...
Physicals gels formed by low molecular weight organic gelators (LMMOG) are composed of a rigid network formed by the gelators, in which is trapped a large quantity of solvent. Gathering properties of both liquids and solids, they find applications as functionalized nanomaterials in diverse domains, although applications suffer several limitations, such as the unexpected collapse after some...
Oppositely charged polyelectrolyte (PE)-Surfactant Complexes (OP-SCs) have attracted much interest over the past decades. Not last because of their relevance in numerous household applications such as detergency and paints, or as rheological modifiers [1]. In general, these mixtures form clear, homogeneous solutions if either an excess of PE or surfactant charges is present and precipitates...
Among the numerous techniques of dye removal, adsorption on modified polymers is a procedure of choice; due to easy handling and removal efficiency [1]. Polyvinyl alcohol (PVA) is a water-soluble synthetic biopolymer, biodegradable, and non-toxic. However, to improve the functionality of PVA, this polymer is often combined with nanoparticles and other synthetic and natural polymers, such as...
Polymer conformations and self-assemblies can be modularly controlled using bottlebrush-like architectures, where the side chain brushes are physically bonded to the polymer backbones. As the side chain brush molecules can be considered as solvents, the architecture is a specific case of polymer-solvent complexes. Competition between attractive and repulsive interactions is crucial for the...
The relevance of solvents and technical treatments used for wood-based products requires a proper identification of the specific role of each solvent on wood biopolymers to better understand their influence on wood properties. In particular, wood impregnated with aqueous solutions of organic solvents has shown to give rise to a stronger swelling than that observed in pure water. This...
Syndiotactic polystyrene (sPS) is a stereoregular polymer with a very complex polymorphic behaviour capable of forming co-crystals (molecular-complex crystalline phases) with many low molecular mass guests. In particular the formation of co-crystalline forms with optically active molecules (chromophore, fluorescent, photoreactive), magnetic and polar moelcules has been reported and films...
Polymer inclusion membranes used for selective transport and separation of metallic ions has emerged in recent times. Their expansion depends on the method of preparation and the study of their structure. In this paper, an improvement of a novel category of thin films for performing ions separation was reported. The membrane was elaborated using a mixture of polymers: cellulose triacetate...
We report the facile fabrication of transparent and high-performance moisture barrier material (SC nanocomposite) using surface-modified bentonite clay (SC) as nanofiller and glycidyl silane as a surface-modifier/binder via simple, cost-effective and mass-producible process. SC is synthesised using a base-catalysed sol-gel process; their hydroxyl surfaces are decorated with glycidyl ligands to...
