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Cell behaviors are regulated by a dynamic and complex environment characterized by biophysical, mechanical and biochemical properties. However, most works regulate cell behaviors under static conditions or by external factors. To control cell adhesion and proliferation with a dynamic and mechanical environment, we pattern the surface on self-healing copolymer P(MMA/nBA). The copolymer P(MMA/nBA) with the composition of 48/52 (MMA/nBA) recovers nearly 100% of its original tensile strains after 86 h of recovery from deformation. The physical patterns on P(MMA/nBA) film are obtained over large areas and the size of the hole and the width of connecting bar are in line with the copper grid specifications. The patterned surface tends to be flat after 12 h with almost 75%-80% recovery. Compared with cell incubation on polystyrene flat and patterned surface of P(MMA/nBA) film without self-healing capability, the number and morphology of cells are well manipulated on the patterned surface of self-healing P(MMA/nBA) film. This approach provides a convenient method for dynamically regulating the cell behaviors on the surface of self-healing materials without chemical or biological modifications.

Equilibrium swelling test was employed to determine the swelling responses of Fluororubber (FKM) and Fluorosilicone Rubber (FVMQ) in different types of solvents, and the one-dimensional solubility parameters of FKM and FVMQ were obtained with a range of 17–25 MPa1/2 and 16–20 MPa1/2 respectively. It was attempted to calculate the three-dimensional solubility parameters (HSP) of FKM and FVMQ by using a professional computer software, and a new type of bio-fuel, represented by biodiesel, was further selected as an object in this work to investigate its swellability. Flory-Huggins interaction parameter (χHSP) between FKM, FVMQ and each solvents used in this work was calculated by HSP values, and the results turned out that the swelling ratio (q) decreased with increasing χHSP value. By mathematical fitting, two functional relationships between q and χHSP for FKM and FVMQ were achieved to predict the swelling properties of rubber in fluids. The increasing use of biodiesel with their effect on rubber materials has become an important topic of industrial research. The second components, including ethanol and ethylene glycol, were added into biodiesel with the purpose of cost reduction, which however might cause a critical increase of rubber swelling. One of the possible applications of χHSP values is the prediction or explanation of swelling behavior. Therein, χHSP values between FKM, FVMQ and biodiesel/additive blends were calculated and found that χHSP firstly decreased and then increased with increase of the additive (ethanol and ethylene glycol) content. Taking advantage of this tendency one can predict the swelling properties of rubber products in the biodiesel blends and provide an important reference for such applications in liquid medium.

In search of simple approaches to rationally modulate the single-molecule magnet behaviors in polynuclear lanthanide clusters, a new system containing two structurally closely related rhombus-shaped Dy4 clusters, Dy4(tmhd)4L6(μ3-OH)2·5CH3CN (1) and Dy4(acac)4L6(μ3-OH)2 (2) (HL = 5-(4-ethyoxylbenzylidene)-8-hydroxylquinoline, Htmhd = 2,2,6,6-tetramethyl-3,5-heptanedione and Hacac = acetylacetonate), have been obtained by employing two dysprosium β-diketonate salts to react with a bidentate Schiff base ligand (HL). The two Dy4 clusters have similar structures and possess a structure in which four Dy3+ ions remain in a perfect plane with a rhombus-shaped geometric construction. Dynamic magnetic analysis revealed different single-molecule magnet (SMM) behaviors occurs in 1 and 2. Under zero direct-current (dc) field, 1 displays typical SMMs behavior with ΔE/kB = 39.6 K and τ0 = 2.1 × 10−6 s. However, for 2, a peculiar feature of the χ″ versus temperature curves is that more than two peaks that are frequency-dependent are revealed, indicating the occurrence of multifold relaxation processes that lead to two ΔE/kB (31.3 K and 81.6 K) and pre-exponential factors (τ0 = 3.1 × 10−6 s, τ0 = 2.2 × 10−7 s).

Two new Dy2 compounds, namely, [Dy2(dbm)4(H2L)(CH3O)(CH3OH)] (1) and [Dy2(dbm)5(H2L)] (2) (dbm = dibenzoylmethane, H3L = (2E,N′E)-2-(hydroxyimino)-N′-(pyridin-2-ylmethylene)propanehydrazide, based a polydentate Schiff base ligand have been synthesized, structurally and magnetically characterized. The single-crystal X-ray diffraction research show that both compounds 1 and 2 are binuclear structures. The only difference is that two methanol molecules coordinated to Dy(III) ion in 1 instead of a dbm− coordinated to Dy(III) ion in 2. Magnetic property measurements indicate that they exhibit distinct slow magnetic relaxation behaviors (ΔE/kB = 0.87 K for 1 and ΔE/kB = 18.68 K for 2). This work revealed that the different solvent induced slight disparate structural and magnetic behaviors of two Dy2 compounds, which may provide an effective approach for tuning slow magnetization relaxation behaviors in polynuclear Ln-clusters.

Equilibrium swelling measurement was employed to correlate the Hildebrand (one-dimensional) solubility parameter (δ) of styrene butadiene rubber (SBR) with using different kinds of solvents. The δ was estimated to be a range from 17 MPa1/2 to 19 MPa1/2. It was attempted to calculate the three-dimensional solubility parameter (HSP) of SBR by inputting the swelling data into a professional software program, and the output results were δd = 18.0 MPa1/2, δp = 2.9 MPa1/2 and δH = 2.3 MPa1/2. A new Flory-Huggins interaction parameter (χHSP) between SBR and solvents was calculated by HSP values for the purpose of better predicting rubber swelling responses. The results turned out that the swelling ratio (q) increased with a decrease of χHSP value, showing a roughly linear relationship. Furthermore, a correlation index relating to χHSP value was introduced and mathematical fitted as a functional equation in this work. By using this equation, it is easy to characterize the relative interactions between SBR and each ingredient involved in the formulation and make a pre-screening of the candidate additives for the formula design. Taking advantage of this method one can response better to the challenges in selecting the most suitable additives and replacing the outdated ones by the new emerging ones, bio-sourcing with environmentally friendly ones in particular.