Hansen Solubility Parameters Theory Research Articles

Hansen solubility parameters obtained via molecular dynamics simulations as a route to predict siloxane surfactant adsorption

Hypothesis: The Hansen Solubility Parameters (HSP) derived from Molecular Dynamics (MD) simulations can be used as a fast approach to predict surfactants adsorption on a solid surface.Experiments and simulations: We focused on the specific case of siloxane-based surfactants adsorption on silicon oxide surface (SiO2), encountered in inkjet printing processes. A simplified atomistic model of the SiO2 surface was designed to enable the computation of its solubility parameter using MD, and to subsequently determine the interactions of the SiO2 surface with the siloxane-based surfactant and the various solvents employed. Surfactant adsorption was characterized experimentally using contact angle goniometry, ellipsometry, XPS and AFM.Findings: Comparison of the numerical results with experiments showed that the HSP theory allows to identify the range of solvents that are likely to prevent surfactant adsorption on the SiO2 surface. The proposed approach indicates that polar solvents, such as acetone and triacetin, which are strongly attracted to the silicon oxide surface might form a shield that prevents siloxane-based surfactants adsorption. This simple approach, can guide the selection of adequate solvents for surfaces and surfactants with specific chemical structures, providing opportunities for controlling interfacial adsorption.

Evaluation of the Antifoaming Effect Using Hansen Solubility Parameters.

The appearance of foam in various industrial processes can cause challenges. Antifoaming agents are widely added to suppress foam. To exert a defoaming effect, affinity between the main foam-generating component and the antifoaming agent is an important criterion for selection of an antifoaming agent. The Hansen solubility parameter (HSP) can be used as an index to show the affinity between substances more quantitatively, simply, and accurately. The Hansen solubility sphere method was used to measure the HSPs of antifoaming agents and a foam-forming surfactant. Various antifoaming agents were added to a surfactant solution, and the defoaming effect was evaluated. Correlations of 0.953–0.860 confirmed a relationship between affinity of the antifoaming agents for the surfactant based on HSP theory and the defoaming effect. It is suggested that use of HSP as an indicator can facilitate selection of the most suitable antifoaming agent for the process.

Revealing the Influences of Solvent Boiling Point and Alkyl Chains on the Adlayer Crystallinity of Furan-Diketopyrrolopyrrole-Thienylene Copolymer at Molecular Level.

Crystallinity of the polymer poly(3,6-difuran-2-yl-2,5-di(2-octyldodecyl)-pyrrolo[3,4-c]pyrrole-1,4-dione-altthieylenevinylene) (PDVF) adlayers casted from low-boiling-point (L-bp), medium-bp (M-bp), and high-bp (H-bp) solvents was investigated through scanning tunneling microscopy (STM) and analyzed by the assistance of Hansen solubility parameter (HSP) theory and molecular dynamics (MD) simulations. Crystallinity of the PDVF adlayers increases evidently from the L- to H-bp solvents. Also, the solvent with an alkyl chain such as ethylbenzene (EB) facilitates in improving the crystallinity than the one without an alkyl chain such as chlorobenzene (CB) if the solvent bp is present in the same group. The HSP space discloses that EB is a marginal solvent for PDVF in contrast to CB. Quasi-isolate PDVF in the EB solution revealed by MD simulations facilitates the formation of crystallized domains through surface assembling mechanism. However, in CB, interconnected PDVF molecules through intermolecular overlapping tend to generate amorphous structures through direct deposition of the preformed structures in solution.

Adaptation of Hansen solubility parameter in evaluating transparency of composite materials

In the preparation of polymer-based functional materials, it is often difficult to express the desired function using a single substance. Thus, multiple materials are often combined to achieve a desired function using methods such as the addition of a filler or lamination. However, when materials are mixed using a filler, the transparency of the polymer decreases. Therefore, a prediction indicator for transparency is needed. In this study, we focused on using the Hansen solubility parameter (HSP) as a predictor of transparency. The value of δd, which is the dispersion force term of the solubility parameter, is considered to be related to the refractive index of the solvent. Silica particles were selected as model particles, and the HSP value was determined. We examined the possibility of evaluating the transparency in a solvent containing silica particles based on the HSP value, and our results indicated that a smaller difference in δd between the particles and solvent corresponded with a higher transparency. The HSP value could be used as an index for evaluation of the dispersibility and solubility of the polymer. By using HSP theory in the material design of composite materials, it is thus considered possible to use the same index to simultaneously evaluate the dispersibility evaluation and predict the transparency of the filler.

Exfoliating two-dimensional materials into few layers via optimized environmentally-friendly ternary solvents

Exfoliation of two-dimensional (2D) materials is an issue of concern among scientific researchers. This is because many solvents such as N, N-dimethylformamide and N-methyl-2-pyrrolidone that are capable of better dispersion of 2D materials are relatively toxic and nonvolatile. This work focused on the reasonable design and mixture of two or three less toxic and volatile solvents based on Hansen solubility parameters theory to demonstrate the excellent exfoliation of 2D materials particularly reduced graphene oxide (rGO) and black phosphorus (BP). Polyvinylpyrrolidone (PVP) was introduced as a surfactant to functionalize rGO to help improve its dispersion. Results showed that PVP could effectively functionalize graphene. Few layers of rGO and BP were facilely achieved with 2–3 nm thickness from the use of the designed solvent mixtures, indicating the accomplishment of solvent mixtures in exfoliation/dispersion roles instead of the use of other toxic and nonvolatile solvents.

Optimizing Dispersion, Exfoliation, Synthesis, and Device Fabrication of Inorganic Nanomaterials Using Hansen Solubility Parameters.

Hansen solubility parameters (HSPs) were established by Hansen in 1967 and predict miscibility between different material systems. So far, HSP theory works across polymers, crystalline bulk solids and nanomaterials and can be used to identify single solvents or, more likely, blends of solvents that deliver not only the initial solubility but also control it during reaction processes. This minireview summarizes the recent progress on HSP theory to optimize dispersion, exfoliation, synthesis, and device fabrication of inorganic nanomaterials. First, we briefly introduce HSP theory and determination of HSPs. Then, we discuss in detail the utilization of HSPs for inorganic nanomaterials, focusing on carbon nanomaterials, two-dimensional non-graphene nanomaterials, and metal oxide nanoparticles. Finally, challenges and perspectives of HSP theory in inorganic nanomaterials are reviewed.

Evaluation of the influence of fine particle surface modification with the Hansen solubility parameters

Abstract In this study, we determined the Hansen solubility parameters (HSPs) of metal fine particles by experiments based on the Hansen solubility sphere method. A silane coupling treatment was applied to the metal fine particles to determine the HSPs from their dispersibilities. We examined changes in the HSP values after treatment by a silane coupling. We confirmed that the treatment with silane coupling agents, caused the HSPs of the particles to tend towards the HSPs of the surface treatment agent. We suggest that HSP theory is useful for selection of silane coupling agents.

Effect of reduction methods and functionalization on the dispersion of graphene in epoxy

Poor dispersion between graphene nanofiller and polymer matrix would limit the development and application of the polymeric composites. In our study, three reduction methods, chemical reduction using hydrazine hydrate (N2H4·H2O), high temperature, and solvothermal methods were used to reduce graphene oxide; then reduced graphene oxide (RGO) were further functionalized by sodium dodecyl benzene sulfonate (SDBS) and cetylpyridinium chloride (CPC). The functionalized RGO (FRGO) was characterized with Fourier transform infrared spectroscopy (FTIR), and Raman spectroscopy, respectively. Subsequently, the studied RGO was incorporated into epoxy resin to fabricate composites. Hansen solubility parameters (HSPs) theory was used to predict dispersion of studied RGO in epoxy resin. The compatibility of different RGO with epoxy was calculated by HSPs and compared with the real dispersion of RGO and FRGO in epoxy resin, which was explored through light optional microscopy (LOM). The results indicated that the dispersion of studied RGO in epoxy predicted by HSPs theory is in a good agreement with the experimental results.

Study on dispersion of reduced graphene oxide on physical performance of Polyvinylidene fluoride composites by Hansen solubility parameters

Poor dispersion of graphene in solvents and polymers remains a critical obstacle in practical application of poly(vinylidene fluoride) (PVDF) composite which loading graphene as filler. In order to inhibit the aggregation of reduced graphene oxide (RGO), two dispersants, polyimide (PI) and polyaniline (PANI), were used to modify RGO via in situ polymerization. The functionalization of reduced graphene oxide was characterized by Fourier transform infrared (FT-IR) and X-ray diffraction (XRD). Hansen solubility parameters (HSPs) theory was an effective way to investigate the compatibility of reduced graphene oxide in various solvents and polymers. Light optical microscope was employed to evaluate actual dispersion of functionalized RGO within the PVDF matrix. From the practical consideration, the dielectric and dynamic mechanical properties of PVDF and the composites were tested by dielectric impedance spectrometer and dynamic mechanical analysis (DMA), which illustrated the dispersion of reduced graphene oxide in poly(vinylidene fluoride) was closely related to physical performance of composites.

A facile method to synthesize mussel-inspired polydopamine nanospheres as an active template for in situ formation of biomimetic hydroxyapatite

In this study, Mussel-inspired polydopamine (PDA) nanospheres were synthesized via spontaneous oxidative polymerization of dopamine hydrochloride (dopa-HCl) in a deionized water-alcohol mixed solvent at room temperature and atmospheric air, under alkaline condition. Field-emission scanning electron microscopy (FE-SEM) demonstrated production of sphere-like shape with a smooth surface and tunable size, while monodispersity increased by utilizing isopropanol instead of ethanol owing to lower Ra values based on Hansen solubility parameter (HSP) theory. Dropwise addition of monomer played an undeniable role in the fabrication of uniform and smaller spheres. The difference of the charge repulsion of constructs in the range of pH led to different dispersive behavior in a variety of solvents, exhibiting versatile applications. The presence of active functional groups on the surface of PDA spheres made them an appropriate option for PDA-assisted biomimetic mineralization of hydroxyapatite (HA), which is the result of the interaction between abundant catecholamine moieties in PDA and Ca+2 ions in simulated body fluid. Bio-adhesive nature of PDA in water and the presence of amino and hydroxyl functional groups support desirable L929 mouse fibroblast cell spreading. The viability of >90% fibroblast cells proved the biocompatibility of polymerized structure. All the achievements indicated that PDA nanospheres provide a biocompatible and bioactive template for green synthesizing hydroxyapatite and the innovative basis for further tissue engineering applications.

Evaluation of adsorption of organic solvents to modified hydrophobic silica adsorbents based on Hansen solubility parameter

• Adsorption of organic substances in aqueous solution was carried out using hydrophobic silica adsorbent. • Adsorbed amount was estimated using HSP theory. • An adsorption amount estimation formula using the difference R a of HSP values was constructed. • It was suggested that affinity is an important factor in adsorption. Adsorption is an effective methodology for the removal of organic matter. Several studies have shown that adsorption performance is dependent on pore size, specific surface area, and the affinity between the adsorbent and adsorbed material. In this study, we concentrated on the effect of the affinity between the surface of the adsorbent and the adsorbed matter by examining the adsorption of organic solvents from organic/aqueous mixtures using three types of hydrophobic silica adsorbents. The Hansen solubility parameters (HSPs) of the adsorbents were determined using the group contribution method. A linear relationship between the logarithm of the amount of adsorbed organic solvent and the difference between the HSP values of the organic solvents and adsorbents was obtained with a high correlation coefficient. These experimental results suggest that the affinity between the adsorbent and adsorbed matter can be well-described by the HSPs of the components.

Controlled surface functionalization of poly(ethylene terephthalate) fibers with varied vinyl monomers via radical graft copolymerization

Surface functionalization of poly(ethylene terephthalate) fibers (PET) via radical graft polymerization can be controlled by identifying and evaluating mutual interactions between different components in the grafting reaction system. Hansen solubility parameter theory could quantify interactions and affinities of the chemical components, including monomers, initiators, polyester, and solvents, in the system and thus can be utilized in control of the radical graft polymerization on polyester fibers. Previous study has demonstrated the control by using the theory but with limitations on certain monomers. Addition of a crosslinker to the graft reaction system could improve grafting of vinyl monomers in varied hydrophilicity and hydrophobicity. Different crosslinkers could vary interactions of the monomer/crosslinker-solvent and monomer/crosslinker-initiator, which have determining impact on the grafting values of different monomers.

Model Protein Adsorption on Polymers Explained by Hansen Solubility Parameters

Hansen solubility parameters (HSP) theory has been successful in explaining the wettability of organic solvents on polymer surfaces and miscibility of different polymers. Here, we demonstrate that the amount of bovine serum albumin (BSA) protein adsorption on different polymer surfaces can also be explained by HSP. Interestingly, the HSP of the adsorbed BSA proteins calculated from the protein adsorption data is different than the HSP of native BSA protein itself. The HSP of the adsorbed BSA proteins are more hydrophobic than the native BSA protein. This observation suggested adsorbed BSA proteins are partially denatured and exposed their hydrophobic core toward the polymer surfaces. These results highlight a new strategic direction to understand interaction of protein with a surface: a theoretical approach that compliments experimental approach. The model in this study could be used to predict the amount of BSA adsorption on a polymer or any other solid surface, if the HSP of that surface is known. Further, the model can serve as a prescreen method to identify surfaces that are problematic at the outset and inform subsequent empirical studies to select packaging that will have the least adsorption for the specific biologic application.

Plasma Treatment of Metal Oxide Nanoparticles: Development of Core–Shell Structures for a Better and Similar Dispersibility

Low-pressure plasma polymerization of cyclopropylamine was employed for the surface functionalization of commercial ZnO, Al2O3, and ZrO2 nanoparticles in a homemade hollow cathode plasma reactor. The analysis of the modified nanoparticles by X-ray photoelectron spectroscopy (XPS) revealed the incorporation of reactive functional groups such as primary and secondary amines, which was confirmed by Fourier transform infrared spectroscopy (FTIR). The raw and the plasma functionalized nanoparticles were evaluated in terms of dispersibility. Application of Hansen solubility parameters (HSP) theory showed that the efficient plasma polymerization that led to the deposition of an approximately 5 nm thick plasma polymer film, as determined by transmission electron microscopy (TEM), causes a similar shift toward the Hansen solubility space for the functionalized nanoparticles and changes their physicochemical affinity within selected solvents, regardless of the kind of nanoparticles used. Hence, a combined exploitat...

Dispersion of pristine and polyaniline functionalized carbon nanotubes in designed solvent mixtures by Hansen solubility parameters

Functionalizing multi-walled carbon nanotubes (MWCNTs) is a novel approach for improving the dispersion of MWCNTs. In this study, MWCNTs were functionalized using polyaniline (PANI). The effects of PANI surface modification on the Hansen solubility parameters (HSPs) of MWCNTs were reported. We studied the dispersion of different MWCNTs in several solvent mixtures based on HSP theory. To replace toxic and nonvolatile solvents for use with different MWCNTs, eight solvent mixtures with low toxicity and volatility were prepared. The dispersions of MWCNTs and PANI/MWCNTs in these solvent mixtures were compared with the dispersions in pure solvents. We found that the MWCNT dispersion is mainly related to the HSPs of the solvents and to the physical properties of solvents.

Understanding Solvent Spreading for Langmuir Deposition of Nanomaterial Films: A Hansen Solubility Parameter Approach.

To prepare high-quality Langmuir films of 2D materials it is important to select a solvent optimized for both exfoliation and spreading at the air-water interface. Whereas it is generally accepted that exfoliation and stabilization of 2D materials is well-described using the Hansen solubility parameter theory, a complementary description of solvent spreading behavior is lacking. To this end we develop an understanding of solvent spreading using a Hansen solubility parameter framework. Our model accurately predicts the behavior of both water-immiscible and water-miscible solvents in Langmuir film formation experiments. We demonstrate that spreading behavior can be modified by controlling the surface pressure of the subphase using an amphiphilic species and accordingly utilize this approach to determine the maximum spreading pressure for a selection of solvents. Ultimately, by building on this understanding we open up additional routes to optimize the preparation of Langmuir films of 2D materials and other nanoparticles.

Direct Exfoliation of High‐Quality, Atomically Thin MoSe2 Layers in Water

AbstractThe discovery of 2D materials has brought us to a conceptually new, wonderful microscopic world. Large surface areas combined with extraordinary electronic, electrochemical, and thermal properties make these atomically thin, layered materials fascinating candidates for diverse applications, ranging from sensing to energy storage and electrocatalytic hydrogen evolution. However, it is essential to solve the problem of scalable and green production of 2D materials before being able to bring them from laboratory to industry. In this sense, the exfoliation of 2D materials in water, free from any stabilizer, is very important since it is a gateway technology toward their production as well as future applications. This Communication reports the direct exfoliation of atomically thin MoSe2 layers in water, which bypasses the Hansen solubility parameters theory and suggests potential for liquid‐phase exfoliation of 2D materials. A combination of long‐time sonication and high‐speed centrifugation results in a substantial fraction of monolayers. When applied in the field of electrocatalytic hydrogen evolution, these atomically thin MoSe2 layers can significantly outperform bulk MoSe2. The finding may point towards industrial scale production of 2D materials by simultaneously ensuring high product quality, laudable monolayer yield, and good environmental compatibility.

Separation of coal gasification tar residue by solvent extracting

Abstract Coal gasification tar residue (CGTR) is a kind of industrial solid waste produced in the coal utilization process. It demands being correctly disposed due to the toxicity with some carcinogenic aromatic compounds. High heat value of CGTR indicates that it can be a useful energy resource. In this work, 22 solvents with different properties were used to extract CGTR and the Hansen solubility parameter theory was applied to relate with the experimental results. The basic thermo-physical properties of the extracting solvents were analyzed based on the physical property estimation from Aspen plus software. It was supposed that the solvent systems like toluene, n-butyl acetate and n-butyl acetate + dimethyl carbonate could be promising extracting solvents for the effective separation of CGTR in practice.

New insights into polymer-solvent affinity in thin films

Polymer-solvent affinity, estimated from the Hansen Solubility Parameters (HSP), was compared to experimental results of dissolution and swelling of polymer prepared in the specific form of thin film. This was carried out for 3 common polymers (PS, PLA, PMMA) and a series of 16 polar and non-polar solvents. The affinity properties predicted from the calculation of the relative energy distance (RED) values of most of the studied solvent/polymer pairs were in relative good agreement with the dissolution tests performed on the film. In contrast, no clear correlation between the RED and the swelling behavior was found. The observed deviations were attributed to the inability of the HSP theory derived from data acquired in polymer solutions to be extrapolated to the particular case of swollen polymer film.

Pervaporative performance of PEBA and PDMS based commercial membranes in thiophene removal from its binary mixtures with hydrocarbons

This work describes vacuum pervaporation tests which were performed to identify the influence of five hydrocarbons typically presented in gasoline, i.e. n-hexane, n-heptane, n-octane, isooctane (2,2,4-trimethylpentane), and 1-octene on thiophene removal efficiency from hydrocarbon/thiophene binary mixtures. Commercial hydrophobic PEBA-based and PDMS-based composite membranes were applied. The impact of process parameters such as feed temperature and feed composition was examined. Experiments performed with various hydrocarbon confirmed, that the membrane performance and overall separation efficiency is influenced by the physiochemical properties of the mixture components (solute and solvent) and the differences in the affinities towards a given membrane. Permeate fluxes and corresponding separation factors presented typical trade-off regardless the type of membrane and solvent. The separation factors were higher in the case of the PEBA membrane which corresponded with the Hansen's Solubility Parameters Theory. The batch pervaporation removal of thiophene from isooctane was also modeled, proving that the PEBA membrane is more effective than the PDMS one. Solvents fluxes were 3 orders of magnitude higher than solute ones, therefore Pervaporation Separation Index (PSI) should be used only as a preliminary assessment of the membrane performance.