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UV-curable polymer composites are of importance in industry, biomedical applications, scientific fields, and daily life. Outstanding physical properties of polymer composites were achieved with nanoparticles as filler, primarily in enhancing mechanical strength or barrier properties. Structure-property relationships of the resulting nanocomposites are dictated by the polymer-filler molecular architecture, i.e. interactions between polymer matrix and filler, and high surface area to volume ratio of the filler particles. Among monomers, acrylates and methacrylates attracted wide attention due to their ease of polymerization and excellent physicochemical and mechanical properties of the derived polymers. We prepared and photopolymerized two series of formulations containing hydrophobized silica nanofiller (Aerosil R7200) dispersed in 2-hydroxyethyl acrylate (HEA) or polyethylene glycol diacrylate (PEGDA) monomers. We compared selected physical properties of the formulations, both before and after photocuring; specifically the viscosity of formulations and dispersion of the filler in the polymer matrices. Additionally, we estimated the bulk Poisson׳s ratio of the investigated nanocomposites. This article contains data related to the research article entitled "Nanoscale Young׳s modulus and surface morphology in photocurable polyacrylate/nanosilica composites" (Gojzewski et al., 2017) [1].

We studied quantitatively nanomechanical properties (Young’s modulus, adhesion force) and surface morphology of two types of model polymer-nanosilica composites. High-resolution structure-property maps were obtained using atomic force microscopy (AFM) in the non-resonant dynamic imaging mode (Quantitative Imaging, QI) by the collection and evaluation of a large number of force-distance curves. The Derjagin-Muller-Toropov (DMT) mechanical contact theory was applied. Interactions between the filler (Aerosil R7200) and two matrices (based on 2-hydroxyethyl acrylate and polyethylene glycol diacrylate) resulted in the appearance of differences in the interphase structure of the two types of composites. The main goal of the paper was to reveal these differences by determination of the mechanical nature of the polymer-particle interphase through systematic AFM indentations providing excellent mapping details. We focused on how the sub-microstructure of the nanocomposites is influenced by the presence of the varied filler contents. The AFM nanomechanical analysis is supported by a standard AFM imaging and SEM morphological observation as well as polymerization kinetics measurements. Our work serves to give a better understanding of the mechanical behaviour and properties of nanocomposites, particularly at the filler-matrix interphase. The article also discusses the measuring accuracy and possible method errors related to the QI mode in the AFM.

Herein we report a facile and scalable synthesis of highly nitrogen-doped porous carbon materials with tunable morphology. Bio-based imidazolium derivatives made from natural amino acids and dioxo-derivatives are employed as precursors, exhibiting an analogous behavior during carbonization to classical ionic liquids. Utilization of systematically controlled salt templating methods yields nitrogen-doped carbon materials with high surface areas of up to 2650 m 2 g −1 and morphology-engineered structures such as monolithic or highly extended, sheet-like carbons. We believe that the presented approach represents an alternative and sustainable platform towards the rational design of carbon materials possessing controlled nanoporosity and functionality.

Copper phthalocyanine (CuPc) dissolved in trifluoroacetic acid (TFA) is deposited on solid SiO2 surfaces by solvent evaporation. The deposited CuPc aggregates are investigated by atomic force microscopy (AFM). The CuPc deposits were prepared by spin casting, dip coating, and spray deposition. Depending on the amount of deposited CuPc the aggregate morphology ranges from small individual domains to mesh-like multilayers. Each domain/layer consists of many parallel stacks of CuPc molecules with the square, plate-like molecules piled face-wise within each stack. The parallel stacks are attached sideways (i.e., edgewise attachment molecularly) to the substrate forming “nanoribbons” with uniform thickness of about 1 nm and varying width. The thickness reflects the length of a molecular edge, the width the number of stacks. A nucleation and growth model is presented that explains the observed aggregate and multilayer morphologies as result of the combination of nucleation, transport processes and a consequence of the anisotropic intermolecular interactions due to the shape of the CuPc molecule.

The anisotropy of several PVA/magnetosome magnetically textured films has been investigated. The thin film synthesized under the influence of a magnetic field (99 mT) shows the typical behavior of an anisotropic material. The results show that the magnetic field applied during the synthesis promotes an orientation of the chains of magnetosomes and permanent textured film is obtained after solidification.

The article describes the influence of the amount and type of organically modified nanosilica (surface and structure modified Aerosil 7200 and surface-modified Aerosil R711) on the photopolymerization kinetics of tetraethylene glycol dimethacrylate and on the physical properties of nanosilica dispersions in the monomer and the polymer matrix. Kinetic measurements showed that silica addition can accelerate or retard the polymerization depending on the silica content; the magnitude of this affect depends on the type of silica modification and can be associated with stability of silica dispersion (as measured by Zeta potential value). The highest reactivity showed compositions containing 4–5 wt.-% of silica and acceleration of the polymerization seems to result mainly from the increase in the propagation rate coefficient. The composites obtained show a uniform dispersion of nanoparticles within the polymer matrix for the silica content at least several wt.-%. The size of aggregates covered with the polymer layer is between 50 and 150 nm for Aerosil R7200 and 75–300 nm for Aerosil R711.

The adhesion force between a silicon nitride tip and a 1-dodecanethiol monolayer have been measured at different loading rates and different humidity. A way to extract the kinetic and interaction potential parameters for a single molecule interaction is demonstrated. The effect of the increase of van der Waals interaction strength per molecule with increasing humidity is explained by assuming a gradual adsorption of water into the tip surface hollows. The study should help in better understanding of the humidity effect on molecular level and in avoiding the underestimation of adhesion forces in micro- and nano-engineering in ambient conditions.

A suspension of bacterial magnetosomes was investigated with respect to structural and magnetic properties and hyperthermic measurements. The mean particle diameter of about 35 nm was confirmed by transmission electron microscopy (TEM), X-ray and magnetic analysis. The X-ray powder diffraction peaks of magnetosomes fit very well with standard Fe3O4 reflections. The found value for specific absorption rate (SAR) of 171 W/g at 5 kA/m and 750 kHz means that magnetosomes may be considered as good materials for the biomedical applications in hyperthermia treatments. Moreover, they have biocompatible phospholipid membrane.