A series of composite hydrogel films containing 3-aminophenylboronic acid (AAPBA) with different thicknesses based on chitosan (CS) interpenetrating microgels were prepared on glass sheets. The gel film’s response to glucose was measured by ultraviolet spectrophotometry. The results showed that the gel with 10 mol% AAPBA showed the strongest optical response. Alizarin red S (ARS) and methyl orange (MO) were both adsorbed and desorbed from the gel film. The pore diffusion coefficient of the non-interacting solute, methyl orange, showed that the hydrogel had good permeability to water-soluble organic molecules. The apparent diffusion coefficient (8.05 × 10−8 cm2/s) of the thin gel (0.157 mm) was lower due to the influence of the kinetics of the gluconophile bond of 3-aminobenzoborate semisulfate (PBA) or due to a structural rearrangement. The diffusion coefficient of the thicker gel (0.430 mm) was 1.1 × 10−7 cm2/s, and glucose diffusion was the rate-limiting process. The specific amount of ARS bound in the gel was 27 μmol/mL, which was consistent with the amount of PBA fixed in the gel (25 μmol/mL). MO underwent nonspecific binding in the gel. The photoresponse of the gel toward glucose was reversible under physiological pH. The linear response and stability of the gels toward glucose suggest they may be used in various glucose-sensing technologies.

This research focused on the use of montmorillonite (Mt) clay to eliminate methylene blue (MB) from water and the modeling of the process with an artificial neural network (ANN). The effects of initial MB concentration, contact duration, pH, and temperature on the adsorption efficiency were examined. Maximum adsorption capacity, with 91.3 wt% MB removal at the selected optimum parameters (pH: 12, contact duration: 90 min, temperature: 25 °C, adsorbent dosage: 2 g/L, and initial MB concentration (Ci ): 650 mg/L), was measured as 296.6 mg/g. Langmuir isotherm and pseudo-second-order kinetic models showed the highest correlation coefficients (0.9935 and 0.9999, respectively) to explain the mechanism of the adsorption of MB cations onto Mt. In addition, the maximum adsorption capacity at 25 °C calculated by using the Langmuir isotherm model was determined as 400 mg/g. In the developed ANN model, pH, C i, temperature, and time were considered the input data, and the equilibrium MB concentration (C e) was the output data. While obtaining the ANN model, the data were processed using fivefold cross-validation. Comparing the estimation results with the experimental studies, R 2 = 0.9987 and mean square error (MSE) = 0.00084654 were obtained. Therefore, the C e value estimations were performed with high success rates by using the developed ANN model.

The Helmholtz free energy, A, and the Gibbs free energy, G, of polyethylene (PE) were determined based on its empirical pressure–volume–temperature–entropy equation of state, P-V-T-S Eos, and the empirical partition function, which we reported previously. The PA-VA-TA-SA Eos for the iso-Helmholtz free energy, iso-A, was determined based on the P-V-T-S Eos where the pressure (PA ), volume (VA ), temperature (TA ), and entropy (SA ) satisfied the condition that A is constant. The PG-VG-TG-SG Eos for the G being constant was also determined based on the P-V-T-S Eos. The three-dimensional (3D) plots, 3D plot, with the three axes, x = TA, y = PA, z = VA expressed by the 3D (TA , PA , VA ) and the 3D (TA, VA , SA ) at constant A in PE were determined, where the iso-A processes were characterized assuming that the volume and the entropy in the iso-A process decreased with increasing pressure and temperature, while in the 3D (TG, PG , VG ) and 3D (TG, VG , SG ) plots at constant G in PE, the volume and the entropy in the iso-G process were increasing with increasing pressure and temperature. The empirical partition function for the Helmholtz free energy was expressed by the summation of the terms of T, T 2, and T 4 , the Boltzmann factors with i = 1, 2, 3, and 6 and and the U(V,T = 0 K) term for the zero Kelvin internal energy where the T 4 term and the Boltzmann factors with i = 6 and 3 were dominant negative factors in the A-T relation at the constant V = 1.04 cm3/g. In case of the Gibbs free energy where the partition function was expressed by the summation of the terms of T, T 2, and T 4 , the Boltzmann factors with i = 1, 2, 3, and 6, the U(V,T = 0 K) term, PV and PV(T = 0) terms, the T2 term and the Boltzmann factors with i = 6 and 3 were dominant negative factors in the G-T relation at 1 atm (1.01 × 10−4 GPa), while at high pressure, 1.0 GPa, the PV and PV(T = 0) terms were dominant positive factors.

Polyvinyl chloride (PVC)/Aliquat-336 microspheres were prepared with the phase inversion method and optimized for red Cibacron dye adsorption. Response surface methodology (RSM) was used to maximize the adsorption capacity. The optimized parameters were the PVC fraction in the dimethylformamide (DMF) solvent, the Aliquat-336/polymer ratio, and the volume fraction of ethanol in the water coagulation bath. The model significant parameters found were the Aliquat-336/polymer ratio and the ethanol volume fraction. The maximum adsorption of 73.7425 mg g−1 was obtained by optimization with an Aliquat-336/PVC mass ratio of 1.5 and an ethanol volume fraction of 0.0934. This theoretical maximum adsorption capacity was confirmed with the experimental one, which had a close value of about 70.25 mg g−1. Both intraparticle and interparticle diffusion mechanisms controlled the adsorption kinetics, and the equilibrium adsorption time was established as 180 min.

The improvement of flame retardants in controlling polymer combustion behavior is mainly based on their effect on the polymer thermal degradation behavior. In this article, the Kissinger method and Flynn-Wall-Ozawa method were used to study the thermal degradation behavior of alginate (Alg)/graphene composite fibers. The results of activation energy calculated by the two methods were very consistent. The addition of a graphene-based flame retardant (GO-DOPO-V, where GO represents graphene oxide, DOPO represents 9,10-dihydro-9-oxy-10-phosphoxanthine-10-oxide and V represents vinyltrimethoxysilane) increased the thermal degradation activation energy of the Alg composite fiber and enhanced the thermal stability and flame retardancy of the fiber. The Flynn-Wall-Ozawa method further revealed that the addition of GO-DOPO-V induced a condensation reaction of the polymer at the early degradation stage of the Alg composite fibers, leading to a decrease in the thermal degradation activation energy. At the final stage of the thermal degradation, with the formation of a char layer, the thermal degradation and activation energy of the Alg composite fibers were improved under the action of GO-DOPO-V, and the flame retardancy of the Alg composite fibers was enhanced.

We prepared a nanocomposite (NC) film containing sodium lignosulfonate (LS), polyvinyl alcohol (PVA) and nano-sized cadmium sulfide (CdS) using the thermolysis and ex-situ casting procedures. Samples from the prepared PVA-LS/CdS NC film were exposed to gamma radiation doses (2 − 20 kGy). To study the resultant outcome of the gamma ray irradiation on the optical and color properties of the synthesized NCs, we used UV-vis spectroscopy and the International Commission on Illumination (CIE) color changes technique. When the gamma dose was increased to 20 kGy, the refractive index increased along with a decrease in the direct optical bandgap from 4.41 to 3.90 eV. We attribute this to the dominance of crosslinking that damaged the ordered configuration and thus increased the amorphous phase. This suggests that the gamma radiation can facilitate the spreading of CdS within the composite matrix suggesting an extra compacted structure of the PVA-LS/CdS NC samples. Moreover, the values of Eg, obtained from ε″ vs. energy plots were close to those values obtained by means of Tauc’s relation, indicating that the NC films exhibited a direct allowed transition. Finally, the color changes between the pristine and irradiated samples were characterized. The pristine PVA-LS/CdS NC film exhibited substantial color differences.

Our aim for the research described here was to investigate the effects of the molecular weight (Mw) of the polystrene (PS) latex and the nano-metal oxide (TiO2) content of PS latex/TiO2 nanocomposites on their film formation behavior. With the steady-state fluorescence (SSF) and UV-visible (UVV) techniques, the film formation was monitored through a pyrene-based fluorescence probe. Two instruments were utilized to observe the morphological alterations of the composite films: an atomic force microscope (AFM) and a scanning electron microscope (SEM). Prior to the results experiments, the composite films were prepared in two sets consisting of the latex particles with high Mw (HM) or low Mw (LM), and a dip-coating technique was used at room temperature in order to form multiple layers in each film with TiO2. Then these samples were annealed within the range of 100–280 °C, above the glass transition temperature (T g) of PS. Throughout the annealing process, the film formation was monitored stage by stage based on the fluorescence intensity (I p) emitted from added pyrene and the transmitted light intensity (I tr) levels. All the measurements resulted in completion of film formation, independent of the Mw of the PS latexes or the TiO2 content. However, while the void closure process was not observed in the LM films, whose packaging structure was much simpler than that of the HM films, it was observed in the HM films. At the end of the process, a porous structure was obtained by extracting the PS polymer using toluene as the solvent. The surface appearance of the sample films varied according to both the different amounts of TiO2 layers in the composite films and the molecular weight of the PS latexes. For the HM films, interconnected porosity was produced at all TiO2 contents, whereas interconnected pores were not observed for more than 5 TiO2 layers contents in the LM samples. Furthermore, the spectroscopic measurements and the SEM/AFM images indicated that the film formation of the PS latexes took place primarily in the PS layers on the top and bottom film surfaces.

Ultra-high molecular weight polypropylene (UHMWPP), with a molecular weight of more than 106 g/mol, is expected to have superior properties, such as high mechanical strength, high thermal properties, high chemical resistance and outstanding tribological properties. However, UHMWPP has a very poor processability due to its high melt viscosity. Therefore, we aimed to improve processability of UHMWPP by blending it with a low molecular weight polypropylene (LMWPP). We attempted to improve the interfacial miscibility and intermolecular entanglement of the UHMWPP/LMWPP system by using a kneader machine. The addition of LMWPP tended to change the mechanical, thermal, and rheological properties of the blend system.

The stress-softening effect of rubber-like materials is a phenomenon such that the stress required to attain a given elongation is less during the second cycle of deformation. In practice, stress-softening effects are used as a quantitative measure of strain energy loss. Both rubber reinforcement by fillers and the failure properties of vulcanizates, such as ultimate strength, tearing, cracking, abrasion, and fatigue, are closely related to the processes of energy dissipation during deformation. This paper reports the results of our research on the quasi-static stress-softening effect of vulcanizates of solution-polymerized styrene butadiene rubber (SSBR)/cis-polybutadiene rubber (BR)/silica masterbatches named Eco-Visco-Elastomer composite (EVEC) produced by a continuous liquid phase mixing, taking dry-mixed silica- and carbon black-filled vulcanizates as references. With this liquid phase mixing, the silanization efficiency of EVEC was greatly improved. Compared with the conventional silica filled vulcanizates, the stress softening effect of EVEC was significantly lower at low strain and rose more rapidly with increasing strain, which could be explained by the effects of filler agglomeration and polymer-filler interaction. The less energy dissipation at low strain is mainly due to fewer filler agglomerates, whereas at high strain, for EVEC, it is attributed to more rupture of polymer crosslinks and polymer chains in the matrix with increasing extension, due to higher polymer-filler interaction resulting in less slippage of polymer chains along the filler surfaces.

In this paper the thermal stability properties of poly(3-methacryloylamino propyl trimethyl ammonium chloride) (PMAPTAC) with a series of molecular weights in various salt solutions were investigated by monitoring the apparent viscosity and viscosity retention rate with aging time, for the first time to our knowledge. Secondly, the thermal stability properties of poly(methacryloyloxy ethyl trimethyl ammonium chloride) (PDMC) solution was studied and compared with that of the PMAPTAC solution under the same conditions. The results showed that the viscosity retention rate of PMAPTAC/salt solutions with salinities from 40 g/L to 200 g/L at 85 °C were about 60%, indicating that PMAPTAC had good temperature and salt resistance. Besides, the temperature and salt resistance of PMAPTAC with 0.62 dL/g was better than that of PMAPTAC with 7.55 dL/g under the conditions of this study. In addition, the viscosity retention rate of PDMC/salt solution with the same intrinsic viscosity as PMAPTAC/salt solution was 45%, indicating that compared with PDMC, the PMAPTAC with viscosity retention rate of 60% had better temperature and salt resistance. We suggest the results obtained in this study will not only fill the current gaps in the research of the temperature and salt tolerance properties of PMAPTAC, but also provide support for the potential application of PMAPTAC products in high-temperature and high-salt environments.