Competitive Adsorption between a Polymer and Solvents onto Silica

Abstract

In polymer nanocomposites, particle-polymer interactions play a key role both in the processing and in the final properties of the obtained materials. Specifically, for silica, due to the surface polarity, surface modification is commonly used to improve the compatibility with apolar polymer matrices, in order to prevent agglomeration.In this work, a new way to investigating the polymer-silica affinity and determining dispersibility parameters (HDP) of silica particles in the 3D Hansen space using a solvent approach is proposed. These parameters are estimated from the assessment of the stability of suspensions in a set of organic solvents. Based on the respective locations of the solvent, polymer and silica representative points in the 3D Hansen space, the adsorption of a given polymer in solution in a given solvent can be predicted. This is shown with the industrial precipitated silica Zeosil ® 1165MP in combination with polystyrene and polybutadiene. It is shown that silanization of the silica particles 1 decreases the adsorption of polystyrene, even though due to this surface treatment silica comes closer to polystyrene in the Hansen space. This counter-intuitive effect is rationalized based on the consideration of an adsorption parameter χ S computed from the relative locations of the solvent, polymer and particles in the 3D Hansen space. Basically, this parameter is related to the respective distances of the solvent and polymer representative points to that of the particle in Hansen space.

Partition of Coating Agents between Nanoparticle Interfaces and the Polymer in Nanocomposites

“…45−47 In the case of NPs, adsorption is often studied for suspensions in solvents, for example, by Laurens et al who very recently proposed to correlate polymer adsorption with Hansen dispersibility parameters of silica in a large set of solvents. 48 Samples can then be centrifuged and supernatant concentrations can be determined, for example, by optical spectroscopy or surface tension measurements. 49,50 Typical examples are surfactant adsorption studies on silica NPs in water.…”

“…The higher the free (matrix) concentration, the higher the pressure toward adsorption. Adsorption isotherms have been studied for almost a century because of the obvious importance of interactions with surfaces and interfaces. − In the case of NPs, adsorption is often studied for suspensions in solvents, for example, by Laurens et al who very recently proposed to correlate polymer adsorption with Hansen dispersibility parameters of silica in a large set of solvents . Samples can then be centrifuged and supernatant concentrations can be determined, for example, by optical spectroscopy or surface tension measurements. , Typical examples are surfactant adsorption studies on silica NPs in water. , The shape of the isotherms gives crucial information on the local interactions, while the plateau provides the total adsorbed amount.…”

Using good vibrations: Melting and controlled shear jamming of dense granular suspensions

“…The particles (from Solvay) are made of agglomerated elementary amorphous silica particles of 18 nm diameter. These particles are first organized into a dense fractal network of fractal dimension D f 1 = 2.6 at a size of 50 nm; these primary aggregates are then agglomerated at a larger scale to form the particles [30]. Cryo-SEM images of the surface of single particles (Fig.…”

Effective Industry–Academia Collaboration Driving Polymer Innovation

“…First of all, industrial problems are real scientific challenges. Major scientific papers have been cosigned by industrial and academic partners both at the digital level ,,− and at the experimental one, − demonstrating the common interest and the relevance for the polymer community. These exchanges are also key to ensuring a sustainable economic future for the participating countries.…”

“…As an example, the mechanical behavior of a filled elastomer used in a tire is influencedamong other thingsby the solicitations of the road, the abilities of the driver, or the air pressure inside the inner liner. It is also fundamentally controlled by the details of the chemistry of the polymer used and the interactions between this polymer and the filler. − Understanding the details of such a problem requires therefore scientific knowledge in many fields and cannot be addressed by a single academic laboratory. We believe that industrial companies could be the missing link by leading open research centers , using the same approach NSF or DOE would develop, with the purpose of bringing together researchers from different fields of science toward the same large and ambitious goal.…”