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Studies on modeling and optimization of alkali treatment, investigation of experimental uncertainty and sensitivity analysis of alkali treatment factors of natural fibers are important to effective natural fiber reinforced polymer composite development. In this contribution, response surface methodology (RSM) was employed to investigate and optimize the effect of varied treatment factors (sodium hydroxide concentration (NaOH) and soaking time (ST)) of the alkali treatment of Ampelocissus cavicaulis natural fiber (ACNF) on the tensile strength (TS) of alkali treated ACNF reinforced polyester composite. RSM and multi gene genetic programming (MGGP) were comparatively employed to model the alkali treatment. The best model was applied in Oracle Crystal Ball (OCB) to investigate the uncertainty of the treatment results and sensitivity of the treatment factors. Results showed that increased NaOH and ST increased the TS of the alkali treated ACNF reinforced polyester composite up to 28.3500 MPa before TS decreased. The coefficient of determination (R2) and root mean square error (RMSE) of RSM model were 0.8920 and 0.6528 while that of MGGP were 0.9144 and 0.5812. The optimum alkali treatment established by RSM was 6.23% of NaOH at 41.99 h of ST to give a TS of 28.1800 MPa with a desirability of 0.9700. The TS of the validated optimum alkali treatment condition was 28.2200 MPa. The certainty of the experimental results was 71.2580%. TS was 13.8000% sensitive to NaOH and 86.2000% sensitive to ST. This work is useful for effective polymer composite materials production to reduce the enormous material and energy losses that usually accompany the process.

A fast-swelling porous poly(acrylic acid co-acrylamide) crosslinked by N-Maleyl chitosan superabsorbent hydrogels were prepared by free radical graft copolymerization reaction for partially neutralized acrylic acid (AA), acrylamide (Am) using ammonium persulphate (APS) as an initiator, and N-Maleyl chitosan (N-MACH) as crosslinker. The structure of the synthesized hydrogels were investigated by FTIR spectroscopy and scanning electron microscope (SEM). Acetone and sodium bicarbonate were used as porosity generator (porogens) during the polymerization process. Surfactant (span 80) was used as a micelle template and foam stabilizer. The swelling studies showed improvement of hydrogel behavior with increasing of crosslinker concentration. Otherwise, the porous structure and swelling rate of the hydrogels improved by the incorporation of acetone and NaHCO3. While the incorporation of span 80 in the gelling process can enhance the porosity structure. Morphological studies showed that the porosity generators and surfactant created highly porous structures. The density of all the highly porous superabsorbents hydrogels (HPSH) synthesized was ranged from 0.6 to 1.04 g/cm3. These HPSHs exhibited a higher rate of swelling at time range from 28 to 269 minutes.

Tribo-electric nanogenerator proved a better alternative energy resource for many electronic accessories because of its flexible nature and optimized device properties. It opens up the use of polymer materials (PMs) for harvesting mechanical energy. The disadvantage of the Tribo-Electric Nano Generator (TENG) is likely lower durability, limited short circuit output current, structural changes, post-stress conditions, etc. The purpose of this review article is more focused on systematic and detailed descriptions of TENGs. It gives an overview of tribo-electric polymer-based material formation and triboelectricity generation, structural modes of tribo-electric polymer-based nanogenerators, and its comparisons, measurement, and quantification of tribo-electric polymer-based nanogenerators based on structural and load conditions. Also, this article focused on TNEG efficiency enhancement techniques using various charge control circuit techniques. Possible applications of TNEG for various self-powered devices such as sensor, actuators and bio-harvesting utilities are discussed in detail.

Melt free-radical grafting reactions between ethylene-propylene-dieneterpolymer (EPDM) and glycidyl methacrylate (GMA) were investigated in a batch mixer (170°C, 60rpm). Effect of dicumylperoxide (DCP) initiator and GMA functionalizing monomer concentrations was studied on the grafted EPDM characteristics. Titration results indicated an increase in the graft degree (GD) and gel content (GC) values with increasing DCP concentration as a result of increasing primary free radical concentration and strengthening cross-linking side reaction. FTIR spectrums confirmed that GMA functionalities have been grafted onto EPDM with appearing carbonyl (C=O) peak. After that, the resultant EPDM-g-GMA was used as compatibilizer in PS(polystyrene)/EPDM/PA6 (polyamide6) ternary blends. The effect of rubbery compatibilizer on the blend morphology and mechanical properties was studied. The ATR-FTIR spectra of ternary blends, etched to remove unreacted PA6, demonstrated that the compatibilizing reactions occurred during melt blending. By investigating the SEM micrographs it was revealed that the EPDM-g-GMA compatibilizer at the concentration range of 5 wt.% to 15 wt.% changed the size and type of the blend morphology from separated dispersed to multicore-shell morphology. The finest morphology was achieved by using 7.5 wt.% EPDM-g-GMA. Also, the presence of compatibilizer up to 7.5 wt.% could improve the tensile modulus, yield stress and impact strength, but a decreasing trend was observed at higher concentration of the compatibilizer.

Azidoethyl-2-bromo-2-methylpropanoate (AEBMP) has been synthesized from 2-azidoethanol and 2-bromo-2-methylpropionyl bromide under nitrogen atmosphere. The azido end-functional polystyrene (PS-N3) has been synthesized by Atom Transfer Radical Polymerization (ATRP) technique using AEBMP initiator and styrene in conjugation with Cu(1)Br-bipyridine catalyst at 100°C. The polymerization was performed at three different periods of time, and it was found that both yield and number average molecular weight were increased linearly with increasing reaction time. Thermogravimetric analysis showed that the polystyrene is stable up to 300°C. The molecular weight of the polystyrene was determined using Gel Permeation Chromatography (GPC), and structures of the initiator AEBMP and polystyrene (PS-N3) were characterized by 1H NMR and FT-IR spectroscopy.

Herein a quenched-flow kinetic technique was applied to calculate the rate constants of 1-hexene and 1-octene oligomerization catalyzed by the Cp2ZrCl2 and Cp2HfCl2/MAO catalyst systems, and subsequently a mechanism for the higher α-olefin oligomerization reaction was proposed. The oligomerization results showed that Zr-based catalyst in the oligomerization of 1-octene had the highest activity of 17 in comparison to Hfbased one with an activity value of 15 g oligomer/(mmolCat.h)). According to the obtained results, increasing monomer length led to a shift in molecular weight and polydispersity index value (Mw/Mn) to lower values. Furthermore, the microstructure-viscosity relationship was followed by the calculation of branching ratio and short-chain branching percentage. The obtained results revealed that, the oligomers synthesized by the Cp2HfCl2 catalyst had lower short chain branching ratio value and short-chain branching percentages. According to the kinetic results, the initiation rate constant (ki) of Zr-based catalyst was higher than that of Hf-based catalyst, and the order of calculated propagation rate constants was Zr>Hf for both the 1-hexene and 1-octene-based oligomerizations.

In this work, the compatibility and crystallinity of low density polyethylene (LDPE) and polybutene-1 (PB-1) blends were studied. Various blends of LDPE/PB-1 containing 5, 10 and 20 wt.% PB-1 were prepared in a corotating twin-screw extruder and characterized by scanning electron microscopy (SEM), shear oscillation rheology and wide-angle X-ray diffractometry (WAXD). A matrix-droplet morphology was observed in SEM images, indicating incompatibility of the two polymers in the solid state. Compared to neat LDPE, the relaxation spectra of the blends were broadened, and a slight increase in their relaxation times was observed. The relaxation time of the blends was enhanced by increasing PB-1 content, which was further proved by fitting rheological data in the Carreau-Yasuda model. Deviation of Cole-Cole diagrams from circular shape means that the blend samples were not miscible and the positive-deviation behavior of the complex viscosity and storage modulus from the mixing rule revealed the formation of strong interfacial interactions. The crystallinity of both LLDPE and PB-1 was decreased as a result of blending. The peaks attributed to the form II of PB-1 crystals were eliminated and the peaks related to LDPE were obviously weakened, suggesting to prevent crystallinity of polymers which is associated with a reduction in the total crystallinity percentage for the blend. The reduction of crystallinity was more pronounced in PB-1 phase.

Organocatalysts have attracted enormous interest in the water-crosslinking reaction in silane-grafted polyolefins (SGPOs) system owing to their simplicity, low toxicity and environmentally benign nature compared to organotin catalysts, which are most used in SGPOs system. We focus on organophosphorus compounds including four structure types as organocatalysts; phosphoric acids, phosphoric esters, phosphine oxides and phosphine. The catalytic activities of them for the water-crosslinking reaction in 3-methacryloxypropyltrimethoxysilane grafted ethylene-propylene copolymer (EPR-g-MTMS) system were evaluated using the ATR-FTIR technique and gel-fraction method. The phosphine oxides, phosphoric acids, and phosphoric esters possessing an O=PR3 or O=P(OR)3 unit were found to be an excellent catalyst for the water-crosslinking reaction in EPR-g-MTMS system, while phosphine (PR3) showed no catalytic activity on water-crosslinking reaction in this system, indicating the phosphoryl (P=O) moiety played the important role on catalytic performance of these compounds. In comparison, phosphine oxides showed considerably higher catalytic activities than phosphoric acids / esters. Density functional theory (DFT) calculations demonstrated that the difference of catalytic activity could be attributed to an electron density at P=O moiety making the activation for water through hydrogen-bonding. Finally, the possible catalytic mechanism for the phosphoryl compounds in the EPR-g-MTMS system was proposed on the basis of these results and the SN2-Si pathway in silicate sol-gel chemistry.

Polyolefins have been widely used in the electrical insulation and cable industry in recent years. One of the main usages of these materials is dielectric insulation in coaxial cables. Low attenuation and high signal transmission speed are among the desired features in coaxial cables. The role of polyethylene foam on signal transmission speed in the coaxial cables is the main focus of this study. In the present study, the velocity factor of coaxial samples with different dielectric structures is investigated in both theoretical and experimental approaches. In theoretical formulation, only the void fraction of foam is taken into consideration and other foam properties such as cell density, cell size, and foam structure are neglected. This is the reason for the difference observed between theoretical and experimental results. In theoretical results, a linear increase in the velocity factor is witnessed with the increase of the void fraction while in experimental results there are some exceptions. The foaming degree of the samples was reached 63% causing a 37.7% decrease in theoretical relative permittivity and consequently a 26.8% increase in theoretical velocity factor. On the other hand, up to 36% increase is observed in the experimentally measured velocity factor of foamed dielectric samples compared to the samples with solid polyethylene dielectric.

With the advance of nanotechnology in the insulation materials applications the polymers underwent structural changes, seen as individual and multiple nanoparticles techniques, moreover, frequency response analysis (FRA) provides an important prospective design for multiple nanocomposites applications. In this paper, the experimental work has been done for fabrication new polyvinyl chloride nanocomposites that is using individual and multiple nanoparticles to get low dielectric loss under thermal conditions. SEM images have detected the penetration of nano additives inside polyvinyl chloride materials that are obvious the patterns of utilizing individual and multiple nanoparticles. The series of experiments have performed on multi-nanocomposites of polyvinyl chloride samples in reference to additive free multiple nanoparticles (ZnO, Clay, Al2O3, and Fumed Silica) for controlling on dielectric losses with variant thermal conditions. Also, this paper has been discussed the electric field distribution inside dielectric nanocomposites and multiple nanocomposites for three-core belted power cables based on charge simulation method (CSM). Finally, it has been defined the features layout of using multi-nanoparticles that are enhancing multi-disciplinary properties of polyvinyl chloride as power cables insulation.

In this work, the grafting of maleic anhydride onto two types of linear low density polyethylene with hexene-1 comonomer (LLDPE-H1) and butene-1 comonomer (LLDPE-B1), in the presence of styrene monomer (St) and dicumyl peroxide initiator (DCP) has been studied. The combined influences of MAH, St and DCP on the grafting efficiency via a melt reactive mixing process have been investigated using response surface methodology and the central cubic design has been employed for experimental design and data analysis. IR spectroscopy, contact angle measurements and adhesion test have been used to evaluate the extent of grafting reaction. The results showed that LLDPE-H1 with a 2.2% maximum grafting content showed more grafting content than the LLDPE-B1 (1.86%). This effect could be attributed to the type of comonomer in LLDPE-H1 which made it more prone to chain scission than LLDPE-B1, and a higher level of grafting was achieved. The gel content measurement showed that lower cross-linked structure was formed during the grafting process in the LLDP-H1 than that in the LLDPE-B1. The optimum conditions of maximum grafting and minimum gel content were statically investigated. The optimum percentage of grafting for LLDPE-H1 was 1.82% and it was 1.74% for LLDPE-B1, with the minimum gel content of 6.5% and 9%, respectively. It was found that the amount of grafted percentage was sensitive to the concentrations of the MAH, DCP, and St, while the extent of the gel content was more sensitive to the percentage of DCP.

The present article investigates the implementation of non-minimal state space (NMSS) representation with proportional-integral-plus (PIP) controller for the carbon dioxide absorption process of Shiraz petrochemical ammonia unit. The PIP controller is a logical extension of conventional PI/PID controllers with additional dynamic feedback and input compensators. PIP controller is used for multivariable control without limitation on the number of controlled variables. A Multi Input - Multi Output (MIMO) square model was extracted from step response test. In this way, input water flow rate to carbon dioxide absorption system, the heat duty of input absorbent cooler to tray (1) of absorption tower and re-boiler heat duty of stripping tower are chosen as manipulated variables (inputs), while carbon dioxide mole fraction in absorption tower vapor product, the water mole fraction in absorption tower liquid product and tray temperature No. 36 of stripping tower are determined as controlled ones (outputs). The system identification is performed with three input and three output variables using step response test. As a result, continuous and discrete time transfer function matrices and suitable NMSS model for PIP controller are reported. Finally, in order to evaluate the PIP control performance, the feed flow rate increases by 2%. The results show the proper performance of designed PIP controller for both disturbance rejection and set point tracking.

Prediction of gas reservoir performance in some industrial cases requires costly and time-consuming simulation runs and a strong CPU must be involved in the simulation procedure. Many reservoir parameters conform to a strong aquifer behavior on gas reservoir performance. Effects of parameters, including reservoir permeability, aquifer permeability, initial reservoir pressure, brine water salinity, gas zone thickness, water zone thickness, temperature, tubing diameter, reservoir inclination, the effective intruding angle of the aquifer, and porosity were investigated using Tornado chart, and seven parameters were filtered. Response functions of aquifer productivity index, gas recovery factor, initial maximum gas production, water sweep efficiency, gas production rate, water breakthrough time, and water production were defined statistically, using Eclipse E100 and Box-Behnken design (BBD). According to the formulae generated by the BBD based on simulation runs, reservoir permeability, aquifer permeability, well-head pressure, and gas zone thickness are the most influencing parameters on the gas reservoir performance supported by the strong aquifer. The aquifer was found to be important especially due to its productivity index and sweep water efficiency. Validation of results given by the BBD through simulation runs showed response functions of aquifer productivity index, sweep water efficiency, maximum gas production, and recovery factor are of deviation percentages in the ranges of 10.61%, 6.302%, 3.958%, and 2.04%, respectively.

In this paper, the radiation section of ethylene dichloride (EDC) cracking furnace, considering the chemical reaction, was numerically modelled using computational fluid dynamics (CFD). This study investigated the influence of some parameters such as mass flow rate, the inlet temperature of fluid into the radiation section, and heat flux on the conversion and changes in velocity, pressure, and temperature of the fluid along the coil passes, as well as the outlet stream of the coil. Then, the modelling results were compared with a series of industrial data of an industrial EDC cracking furnace. The results showed that considering the variable heat flux boundary condition is more compatible with the industrial data rather than the constant heat flux boundary condition. Increasing the feed inlet temperature to the furnace, increased the EDC conversion due to the endothermic nature of the thermal cracking reaction. Furthermore, reducing the inlet mass flow rate led to a significant increase in the conversion, temperature, and mass fraction of the products due to an increase in residence time.

Sildenafil citrate (SC) has proved to be an effective and inexpensive drug for the treatment of pulmonary arterial hypertension (PAH). This study aims to synthesize electrospun, submicron fiber scaffolds of poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP) loaded with SC for fast drug dissolution and its potential use in the treatment of PAH. These fiber scaffolds were prepared through the electrospinning technique. The chemical composition of the nanofibers was analyzed by Fourier transform infrared spectroscopy. Thermal stability was studied by thermogravimetric analysis and polymeric transitions by differential scattering calorimetry. Surface analysis of the nanofibers was studied by field emission scanning electron microscopy. The wetting and dissolution time of the scaffolds and drug release rate were studied as well. The drug-loaded PVP fibers showed better quality regarding size and homogeneity compared to drug-loaded PVA fibers. These fibers encapsulated approximately 2.5 mg/cm2 of the drug and achieved immediate controlled released rate, which is encouraging for further studies leading to an alternative treatment of PAH in children.

In this study, carbazole-based hypercrosslinked polymer (HCP) adsorbent was synthesized using the knitting method by Friedel-Crafts reaction. The effects of crosslinker to carbazole ratio and synthesis time on the adsorbent structure were investigated to improve CO2/N2 and CO2/H2 selectivity. Crosslinker to carbazole ratio and the synthesis time was considered in the range of 1-4 (mol/mol) and 8-18 (h), respectively. HCP adsorbents were analyzed by energy-dispersive X-ray spectroscopy (EDS), Fourier-transform infrared spectroscopy (FTIR), and Brunauer-Emmett-teller analysis (BET). The adsorption capacity of CO2, N2, and H2 were measured by carbazole-based HCP and it was correlated with the nonlinear form of the Langmuir isotherm model. The achieved BET surface area of adsorbent with the highest amount of synthesis parameters was 922 (m2/g). The ideal adsorbed solution theory (IAST) was utilized to anticipate CO2/N2 and CO2/H2 selectivity at 298 k and 1 bar. CO2/N2 and CO2/H2 selectivity for adsorbent with the maximum amount of synthesis parameters were 8.4 and 4.4, respectively. The high selectivity values of carbazole-based HCPs are due to the presence of nitrogen atoms in the adsorbent structure and a more robust interaction between CO2 molecules and the adsorbent surface.

The accurate description of the phase equilibria of CO2 and n-alkane multicomponent mixtures over a wide range of temperature, pressure, and n-alkane molecular weight, requires the models that are both consistent and mathematically flexible for such highly non-ideal systems. In this study, a predictive correlation was proposed for the vapor-liquid equilibrium data (VLE) of CO2 and n-alkane ternary systems, based on the Peng-Robinson equation of state (PR EOS), coupled to cubic mixing rules (CMRs). The ternary interaction parameters (TIP) correlation is developed using binary VLE data and tested for CO2 + n-alkane+ n-alkane ternary systems. For this purpose, binary VLE data of CO2 + n-alkane and n-alkane + n-alkane systems for n-alkane from C3 to C24, covering a total of about 70 references, used to correlate TIP in the ranges of 0.5-31 MPa and 230-663 K. Two temperature-dependent TIP correlations, based on acentric factor ratio, have been tuned with more than 2000 data points of the CO2 + n-alkane and the n-alkane + n-alkane binary systems with AARD of 3.13% and 6.71%, respectively. The generalized predictive correlation was proposed based on the proper three-body interaction contributions and successfully tested for VLE data of the CO2 + n-alkane + n-alkane ternary systems.

Experimental study of the effect of gas antisolvent (GAS) system conditions on the particle size distribution of finasteride (FNS) requires a thermodynamic model for the volume expansion process. In this study, the phase behavior of the binary system including carbon dioxide and Dimethyl sulfoxide, and a ternary system comprising carbon dioxide, dimethyl sulfoxide, and Finasteride was studied. The Peng-Robinson equation of state was employed for the evaluation of the fluid phases and a fugacity expression to represent the solid phase. By developing an accurate predictive model, the GAS operating conditions can be optimized to produce particles with no need for a large number of experiments. First, the critical properties of the FNS were evaluated by the group contribution methods. The method of Marrero and Gani was also selected to predict the normal boiling point, critical temperature, and critical pressure. The correlation of Edmister was chosen for the prediction of the acentric factor. The lowest pressures for the ternary system at 308, 318, 328, and 338 K were 7.49, 8.13, 8.51, and 9.03 MPa, respectively. The precipitation of the dissolved finasteride happened at these operating pressures.

Biodiesel is a substitute for fossil fuels which is produced through a transesterification reaction between vegetable oils or animal fats and light alcohols such as methanol or ethanol. In this reaction, along with the production of biodiesel, glycerol as a byproduct and non-reacted alcohol that reduces biodiesel quality is produced. Hence, many studies have been carried out on liquid-liquid equilibrium (LLE) for ternary systems containing biodiesel + glycerol + alcohol. Two phases are formed as 1-rich in biodiesel and 2-rich in glycerol; moreover, alcohol is distributed between these two phases. In this work, based on previous experimental data, the UNIQUAC and NRTL thermodynamic models were used to forecast the composition of the phases. The intermolecular interaction term for each of the models was considered as a linear function of the reverse temperature. In both models, there was no difference between the amount of biodiesel produced from different oils and obtained from the general interaction parameters. Based on the results, the percentage of absolute average deviation for NRTL and UNIQUAC models for biodiesel + glycerol + ethanol system were 1.24% and 2.13%, respectively, and for biodiesel + glycerol + methanol system was 1.13% and 1.71%, respectively.

Due to the limited crude oil resources, the role of enhanced oil recovery (EOR) techniques in the production of the oil that has not been extracted during the primary and secondary oil production techniques is crucial. Gas injection is known as an important EOR technology, but one of the main concerns during gas injection is asphaltene precipitation and deposition within reservoir formation. In this study, the effect of temperature (ranges 376-416 K) and concentration of injected gas (N2 (10, 20 and 40, mole percent) and first separator gas (20, 40 and 60, mole percent)) on the onset pressures and amount of asphaltene precipitation in one of the Iranian oil reservoirs were investigated. Two series of experiments were accomplished on live oil by gravimetric method; first: injection of different concentrationsof nitrogen and first separator gas at reservoir temperature and under different pressures (3000-8000 psia) and second: natural depletion at different temperatures. Besides, the experimental data of asphaltene precipitation due to N2, first separator gas, and also CO2 injection were compared together. Finally, the experimental data were modeled with a solid model. The results indicate that the amount of asphaltene precipitation due to N2 injection (0.1-0.2 wt %) is lower than the first separator gas and CO2 injection at the same concentration. Experiments show that in the range of experimental temperatures the asphaltene precipitation changes up to 0.06 wt %. For pressures below the bubble pressure (~ 4700 psi), precipitation changes directly with temperature, and indirect relation is observed for pressures above the bubble point pressure.

The present research used novel hybrid computational intelligence (CI) models to predict inorganic indicators of water quality. Two CI models i.e. artificial neural network (ANN) and a hybrid adaptive neuro-fuzzy inference system (ANFIS) trained by genetic algorithm (GA) were used to predict inorganic indicators of water quality including total dissolved solids (TDS), total hardness (TH), total alkalinity (TAlk), and electrical conductivity (σ). The study was conducted on samples collected from water wells of Kermanshah province through analyzing water parameters including pH, temperature (T), and the sum of mill equivalents of cations (SC) and anions (SA). A multilayer perceptron (MLP) structure was used to forecast inorganic indicators of water quality using the ANN approach. A MATLAB code was used for the proposed ANFIS model to adjust and optimize the ANFIS parameters during the training process using GA. The accuracy of the generated models was described using various evaluation techniques such as mean absolute error (MAE), correlation factor (R), and mean relative error percentage (MRE%). The results showed that both methods were suitable for predicting inorganic indicators of water quality. Moreover, the comparison of the two methods showed that the predicted values obtained from the ANFIS/GA model were better than those obtained from the ANN approach.

Water in oil emulsion is consider one of the major challenges encountered during production of heavy oil or when applying enhanced oil recovery techniques whether thermal or chemical. In this study stability and rheological properties of hot and cold produced heavy oil emulsions formed due to steam injection processes in Kuwaiti reservoirs were investigated thoroughly over a wide range of operation conditions. The effects of temperature, shear rates, and water cuts on the physical and chemical behaviors of the heavy oil emulsions were examined experimentally in detail. The results showed that cold-produced heavy oil emulsion (CP-HO) is more stable than hot produced heavy oil emulsions (HP-HO) because of its high salinity concentrations and low resin/asphaltene (R/A) ratios, and low PH value. Moreover, a new emulsion viscosity correlation was developed using the experimental data. The proposed model was validated against existed models. The results showed that the developed correlation i more applicable than the existed one in predicting the viscosity of heavy oil emulsions with a percentage of deviation almost less than 5 %.

Antibacterial materials have found widespread interest in different fields nowadays. In this study, curcumin (Cur) was incorporated into the polyvinyl butyral (PVB) matrix by dissolving in ethanol for improving the functional properties of a pure PVB film. We found that Cur was uniformly dispersed in the PVB matrix, which showed good compatibility. Moreover, the incorporation of Cur could also improve thermal stability, hydrophilicity, and mechanical property. The UV-vis spectra of the PVB–Cur film demonstrated that the film could block ultraviolet radiation. Subsequently, the antibacterial activity of the PVB–Cur film was measured by the colony-counting method against S. aureus and E. coli. The results showed that the PVB–Cur film exhibited good antibacterial activity. Therefore, the PVB–Cur film was considered as a promising material for food and medical packaging applications.

The solubility and diffusion coefficient of supercritical CO2 in polystyrene (PS) dynamic melt were studied by using a new constant pressure experimental device. By comparing the experimental results with those of other researchers, the validity of the experimental device and the reliability of the calculated results are verified. The solubility and diffusion coefficient of supercritical CO2 in polystyrene dynamic melts at different temperatures and pressures were obtained. The numerical calculation method, dissolution process, and experimental results are analyzed and compared with that of the static melt. Finally, the effects of stirring speed, pressure, and temperature fluctuation on the solubility and diffusion coefficient are also analyzed.

Epoxy resin is widely used in metal surface protection, because of corrosion resistance and adhesion. However, it’s water solubility, oxygen, and water impermeability are not enough. In this paper, linoleic acid (LOFA) and epoxy resin (E20) were used to synthesize epoxy ester (EL) and grafted with phosphonate esterified acrylic resin (AR-P) to prepare acrylic grafted epoxy ester (EL@AR-P). After modification, water solubility and film-forming property were improved, and the oxygen transmission rate (OTR) and water vapor transmission rate (WVTR) decreased. At the addition of PM-2 at 2%, the OTR, WVTR, and water-uptake rate decreased by 12.9%, 25.0%, and 12.1%, respectively. Subsequently, the modified material was subjected to electrochemical impedance spectroscopy. The low-frequency impedance of EL@AR-P2 is three times higher than EL@AR-P0. After 16 days of immersion, the low-frequency impedance of EL@AR-P2 is 20 times higher than EL@AR-P. Energy dispersive spectrometer and X-ray photoelectron spectroscopy results showed that the P elements were concentrated on the substrate surface and found the presence of P–O–Fe bonds, demonstrating that the phosphonate groups were migrated to the substrate surface to form a chelate layer with the substrate and enhancing the coating adhesion and corrosion resistance. This paper modifies the molecular structure of epoxy resin, which is expected to be an excellent material for anti-corrosion coatings.

Microwave-assisted synthesis of the lipase-catalyzed ring opening polymerization of ε-caprolactone (ε-CL) and ω-pentadecanolactone (ω-PDL) monomers was studied. A series of P(CL-co-PDL), with different molar feed ratios, including (ε-CL/ω-PDL) 100/0, 75/25, 50/50, 25/75, and 0/100, were synthesized. The resulting polyesters were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The microwave-assisted polymerization of the monomers reached high conversions (91–95%) within 60 min. FTIR spectra showed the typical absorption bands of these polyesters. A very intense band in the carbonyl region, which was shifted from 1,720 cm−1 for PCL to 1,732 cm−1 for PPDL homopolymer, as well as peaks owing to methylene groups in the 2,990–2,850 cm−1 range. DSC results revealed that all polyester samples were semi-crystalline. Interestingly, the copolymers exhibited only one melting peak (T m), and their T m values linearly increased from 57°C to 95°C as PPDL concentration was increased. Thermal stability of polyesters also depended on PDL content; an increase in PDL concentration increases polymer degradation temperature (T d).

With the ever-growing demand for 5G networks and the promise of real-time, mission-critical applications, the advanced antennas with high-bandwidth and highly reliable connectivity are urgently needed. 5G networks primarily operate in two areas of spectrum below 6 GHz (known as sub 6) and millimeter wave, which are much higher than the working frequency of 4G cellular networks, thus the previously used materials and integration techniques need to be updated accordingly. In this sense, liquid crystal polyesters (LCP) have been considered as ideal high performance microwave/millimeter wave (mm-wave) substrate and packing materials due to their outstanding properties. More specifically, the LCP normally exhibit good thermal stability, low water absorption, stable dielectric constant and loss tangent in millimeter wave frequency range, which leads to the increasing research interests of LCP for 5G devices application in both academia and industrial fields. However, the review articles focusing on the chemistry and materials aspects of LCP intended for 5G application are unexpectedly limited. In this article, we will summarize the research progress of LCP materials used in 5G networks in the view of polymer science and engineering. More specifically, the polymerization, chemical structure, aggregated state, properties, modification and processing of typical LCP are reviewed, which would be useful for promoting practical application of the LCP in key devices of 5G networks.

Modern microelectronics devices urgently request low dielectric constant materials with commendable mechanical properties. Novel fluorinated poly(aryl ether)s (FPPEs) were prepared by traditional polycondensation of 4-(4-Hydroxylphenyl)(2H)-phthalazin-1-one (DHPZ), Bisphenol AF (BAF) and Decafluorobiphenyl (DFB) to study bulky phthalazinone effects on mechanical and dielectric behavior of polymers. After the introduction of phthalazinone moieties, FPPEs showed excellent solubility to readily solve in many organic solvents like NMP, DMAc, CHCl3, and THF. Simultaneously, they exhibited relatively high glass transition temperatures (Tgs) from 180 °C to 294 °C, increasing with the content of phthalazinone groups. The FPPEs still possessed excellent thermal stability with decomposition temperature up to 514 °C and char yield at 800 °C as high as 56% under nitrogen atmosphere. FPPE films showed good mechanical strength with tensile stress higher than 68 MPa and modulus surpassing 10.8 MPa, also increasing with phthalazinone concentration. The dielectric property of FPPEs was investigated with impedance analyzer. FPPE8020 and FPPE 6040 showed dielectric constant from 3.10 to 3.30 and dielectric loss of 0.005–0.008 under a large frequency range of 0.02–60 GHz. The phthalazinone moieties mainly contributed to the decrease of dielectric constant. The results evidently suggest FPPEs as commendable candidate for those high-tech electronic applications.

Various phthalonitrile-based resins were prepared and their copper clad laminates were fabricated in this work. The curing behaviors and mechanisms were investigated by Dynamic rheological analysis (DRA) and in-situ FTIR. Results indicated that all phthalonitrile-based resins possessed wide process temperature windows and exhibit good processability. However, phthalonitrile-based resins resulted to various final crosslinking network in the presence of various catalyst/curing agents. Phthalonitrile-based copper clad laminates (CCL) were fabricated with hot-press mold technology. Mechanical properties of the CCL including flexural strength/modulus and peel strength were discussed, accompanied by the investigation of fractural surface of the laminates. Glass transition temperatures of the laminates were studied by both Differential scanning calorimetric (DSC) and Dynamic mechanical analysis (DMA). Then, fractural surface of fiber-reinforced composite laminates was investigated by Scanning electron microscope (SEM) and Micro slicing image (MSI). Results confirmed the satisfactory interfacial adhesion between resin matrices and fibers, which resulted to excellent mechanical properties of composite laminates. Then, dielectric properties of various composite laminates were investigated to evaluate their applications in the field of PCB substrates. Moreover, final dielectric properties of various phthalonitrile-based composites were discussed based on the transformation of molecular structures according to the polymerization mechanisms.

With the rise of the fifth-generation (5G) mobile communication, electromagnetic interference (EMI) and radiation become progressively serious toward electronic devices and human health, resulting in an increasing demand for EMI shielding materials. Polymer-based EMI shielding materials have drawn considerable attention in relevant industries and academia owing to their low density, easy processing, and superior flexibility. In this review, we systematically discuss the development of polymer-based shielding materials fabricated by using polymers as matrices and precursors. The architecture design of polymer composites is emphasized including homogenous structure, porous structure, laminated structure, and segregated structure. Specific attention is also given to the polymer derivatives from synthetic and natural polymers. Finally, we summarize the recent advancements and our guidelines for the development of polymer-based EMI shielding materials in the 5G era.

High-performance polymer materials with low dielectric constant and low dielectric loss have been widely used in high-speed communication network. This review briefly introduces several common polymer materials, including polyimides, poly (benzoxazole)s, poly (aryl ether)s, poly (tetrafluoroethylene), and various porous polymers. Moreover, the preparation technology, various properties and applications of common low-dielectric polymers are discussed. Based on the desired properties and requirements for applications as low dielectric materials, the possibility of further development of porous polymer materials is discussed.

A new type of phthalonitrile-etherified resole resin (PNR) was synthesized from resole resin and 4-nitrophthalonitrile. The differential scanning calorimetry results showed that the curing temperature of PNR is lower than that of phthalonitrile resin. Excellent thermal stability and bonding properties were obtained after curing at 220°C. TGA showed that in air, the temperature of 5% weight loss (T 5%) of the cured PNR was 446°C, approximately 41°C higher than that of resole resin (RS), and the char yield at 800°C increased from 4% for RS to 33% for PNR. The shear strengths of PNR at room temperature and high temperature were increased by 8% and 133%, respectively, over those of RS, and after aging at 350°C for 2 h, these values were increased by 262% and 198%, respectively, over those of RS. Its excellent curing behavior, heat resistance and high bonding strength show that PNR can be used as a high temperature-resistant adhesive.

A research is reported on the nanomechanics and tribology of the Arboblend V2 Nature biopolymer (a 100% bio-based material, biodegradable, or resistant depending of application), being a mixture of different biopolymers such as lignin, polylactic acid, cellulose, biopolyamides, and other natural additives. The specimens were made by an industrial-scale injection molding machine. The nanoindentation characterization have unveiled that an increase in processing temperature from 160°C to 170°C produces a rise in hardness and elastic modulus of ∼20%. Tribological characterization against a bearing-steel counterface has shown that for both processing temperatures, the increase of the applied load or the increase of sliding speed will produce an increase of the friction coefficient (µ) and wear. At an applied load of 1 N (contact pressure of 104 MPa) and tracks in a direction perpendicular to the surface textured lines, the lowest µ ∼ 0.148 are for samples made T = 170°C, while for tracks parallel to the textured lines, the lowest µ ∼ 0.059 is obtained for samples made at T = 160°C. Experiments made at different ambient humidity have established that friction coefficient is higher at 0% RH or at 75% RH than at 33% RH. Our results show that the biopolymers Arboblend V2 Nature is a candidate to substitute some popular fossil-based thermoplastics in numerous tribological industrial applications.

Sulfopropylated polysilsesquioxane and –COOH containing fluorinated sulfonated poly(arylene ether sulfone) composite membranes (SPAES-SS-X) have been prepared via an in situ sol–gel reaction through the solution casting technique. The composite membranes showed excellent thermal and chemical stability, compared to the pristine SPAES membrane. The uniform dispersion of the sulfonated SiOPS nanoparticles on the polymer matrix was observed from the scanning electron microscope images. Atomic force microscopy and transmission electron microscopy images indicated significantly better phase-separated morphology and connectivity of the ionic domains of the composite membranes than the pristine SPAES membrane. The composite membranes showed considerable improvement in proton conductivity and oxidative stability than the pristine copolymer membrane under similar test conditions.

This study aims to develop an Adaptive Network-based Fuzzy Inference System technique (ANFIS) and using the parameters of a complex mathematical model in the RO membrane performances. The ANFIS was constructedby using a subtractive clustering method to generate initial fuzzy inference systems. The model trained by 70% of the data set and then its validity is examinedby remained 30% data set. The result indicated that this method could predict the performance of the RO membrane faster and more accuratelythan previous numerical techniques. The squared correlation coefficient between real data and predicted data of this technique was 0.9973 for separation factor, 0.9916 for NP and 0.9975 NT, which are better in comparison with numerical methods, and previous Artificial Neural network used by the author to model these membranes. It was observed that the squash factor, reject ratio,and accept ratio has no significant effect on ANFIS performance. Results showed that for all cases better performances achieved when this parameter has a value of more than 0.5, as 0.86 for separation factor, 0.91 for net pre flux,and 0.83 for total flux. This technique just takes a few secondsto model RO membrane performance which is very faster than other numerical methods. So,this technique could be a powerful method to predict RO membranes.

Poly(l-lactide)-b-polyethylene glycol-b-poly(l-lactide) (PLLA-PEG-PLLA) is found to be more flexible than PLLA due to the flexibility of PEG middle blocks. Melt flow and mechanical properties of PLLA-PEG-PLLA were improved through post melt blending with a chain extender (CE). In this work, in situ chain-extended PLLA-PEG-PLLAs were synthesized by ring-opening polymerization in the presence of Joncryl® CE. The influence of CE content (1.0, 2.0, and 4.0 phr) on the gel content, melt flow index (MFI), thermal properties, and mechanical properties of the obtained in situ chain-extended PLLA-PEG-PLLAs was investigated. The gel content of in situ chain-extended PLLA-PEG-PLLA increased while the MFI and degree of crystallinity significantly decreased with increasing CE content. The in situ chain-extended PLLA-PEG-PLLA with 1.0 phr CE showed the best tensile properties. The extensibility of in situ chain-extended PLLA-PEG-PLLA films decreased when the CE contents were higher than 1.0 phr. These in situ chain-extended PLLA-PEG-PLLA films can be used as highly flexible bioplastics.

The chromium/vanadium bimetallic Phillips catalysts developed by our research group have been proved to be a promising process to produce bimodal polyethylene using a single-reactor process. The vanadium loading of CrV-1/1, CrV-1/2, and CrV-1/3 has a significant effect on the polymerization activity, product molecular weight (MW), as well as the molecular weight distribution (MWD). Due to the unstable and easy deactivation of vanadium active centers at atmospheric or low (0.4 MPa) reaction pressure [Macromol. React. Eng. 2015, 9, 462–472], the reaction is carried out at 1.0 MPa to strength the V active center on the activities of ethylene homopolymerization, ethylene/1-hexene copolymerization, and the H2 responds properties. The reaction carried out at higher pressure promotes the polymerization activities. With the same amount of cocatalyst, the highest activity of the three Cr-V bimetallic catalysts CrV-1/1, CrV-1/2 and CrV-1/3 decreases with the increase of vanadium loading. The Cr-V bimetallic catalysts require more cocatalyst than the single metal Cr cat. It was found two obvious peaks in the GPC curves of homopolyethylen and ethylene/1-hexene copolymer. It means that the higher reaction pressure benefits the promotion of the active center of catalyst for higher MW. By increasing the loading from 0.48 wt.% (CrV-1/1) to 0.96 wt.% (CrV-1/2), the molecular weight increases by nearly 30%. Besides, according to the deconvolutions of the GPC curves of homopolymers, ethylene/1-hexene copolymers, and the homopolymers with H2 modulation, the synergetic effect between Cr and V center is presented. As the vanadium loading increases, the active site accounted for the high molecular weight portion increases, and the Cr-V catalyst presents better hydrogen responds. When the partial pressure of hydrogen is 0.1 MPa, the molecular weight is reduced by nearly half. Specifically, the high molecular weight peak is weakened, while the low molecular weight peak is strengthened. The peak position does not change significantly. The higher vanadium content and the greater sensitivity of hydrogen modulation indicate that the vanadium active center has better hydrogen responds than the chromium active center does. The homopolymerization product of the Cr/V-1/1 catalysts exhibits higher tensile strength and elongation-at-break. The tensile properties of the copolymerized product of CrV-1/1 are further improved.

Hyperbranched polymers (HPs), which in terms of structure may be compared to the branching structure of trees, are referred to as tree-like materials, but role of leave in these tree-like polymers is neglected and much attention has only been paid to their branches. In fact, functional groups in these polymers play a vital role the same as the role of leaves in trees. Therefore, in this paper, an attempt has been made to design and synthesize three AB2 monomers containing extra hydroxyl and nitro groups. The benefits of their presence in the structure of produced hyperbranched polyamides (HPs) are investigated. The polymer structure was characterized by FT-IR and 1 H NMR. The solubility of synthesized HPs was studied in different protic and aprotic solvents. The thermal stability of the prepared HPs was investigated by thermogravimetric and differential scanning calorimetric analyses. The photoluminescent properties of the HPs were also investigated.

In this work, the effects of operative parameters on CH4, CO2, O2, and N2 membrane gas separation for poly (4-methyl-1-pentane) (PMP) membrane modified by adding nanoparticles of TiO2, ZnO, and Al2O3 are assessed and investigated. The operative parameters were type and percentage of nanoparticles, and cross membrane pressure. The membrane permeability and selectivity were selected as the responses and indexes of separation process performance. To design the experimental layout, design of experiment methodology (DoE) techniques were used. Further, the separation process was modeled and simulated using artificial intelligence (AI) methods. So, a robust black-box model based on radial basis function (RBF) network was developed and trained with the ability for predicting the performance of membrane process. The developed model could simulate the process and predict the permeability with R2-validation of 0.9. Finally, it was found that addition of nanoparticles and increasing the operative pressure had positive effects on membrane performance. Maximum permeability values for O2, N2, CO2 and CH4 were 181.58, 52.09, 550.85, and 54.26, respectively. The maximum values of validation-R2 of optimum structure for CO2/N2 and CO2/CH4 selectivity were 0.8697 and 0.7028, respectively.

The work was aimed at the investigation of influence of peroxide curing system on cross-linking and properties of rubber compounds based on SBR. First, the temperature of vulcanization and the amount of dicumyl peroxide on curing process and physical-mechanical properties were investigated. Then, co-agents Type I and Type II were added to the rubber formulations cured with peroxide. The results revealed that the increase in temperature leads to the acceleration of curing process while both, curing kinetics and physical-mechanical properties were influenced by the amount of peroxide. The application of Type I co-agents resulted in the acceleration of curing process and increase in cross-link density of vulcanizates, which was reflected in the increase of hardness and decrease of elongation at break. The influence of Type II co-agents on curing kinetics was negligible, while most of them caused the reduction in cross-linking degree of vulcanizates. Type I co-agents contributed to the improvement of tensile strength of vulcanizates, while the influence of Type II co-agents on tensile strength was of minor importance.

Nine different bis(arylimino)pyridine complexes of Fe(III) with different halide substituents (F, Cl, Br, I) at different positions of the iminophenyl group of the ligand have been synthesized, characterized and applied for homogeneous 1-pentene and 1-hexene oligomerization and co-oligomerization reactions after activation with methylaluminoxane (MAO). The best activity in 1-hexene oligomerization (152 kg/mol.h) was observed for 4/ MAO with an iodine substituent in para position of the iminophenyl group. Fluorine substituents in the meta position of the iminophenyl group proved as disadvantageous (1 kg/mol.h) in homo-oligomerization reactions but advantageous in co-oligomerization reactions of 1-pentene and 1-hexene. Obviously, tiny electronic or steric differences at the active sites of the corresponding catalysts are responsible for this result (structure-property relationship). The product distributions of the co-dimerization reactions of 1-pentene and 1-hexene reflected a binominal behaviour with dominating co-products. The ratio of dimers is 1:2:1 (C10:C11:C12) while the trimers (pentadecenes up to octadecenes) show proportions of 1:3:3:1.

Aqueous Polyurethane Dispersions (APUD) have been at the epicenter of the coating industry & research, devising greener solutions to modern coating problems. The formulation of APUDs involves many components namely, polyols, isocyanates, chain extenders, and ionic centers which enable the Polyurethane to be dispersed in water. This reduces the dependence on solvent-based coatings, providing a better and eco-friendly replacement for existing systems. Advantages like ambient temperature curing and excellent adhesion further reinforce the case for APUD. This review encompasses the synergistic effect of said components while painting a vivid picture of how they would affect the final properties of the coating.

Varying amounts of an amorphous poly(1-hexene) (PH, Mv 1.7×106 Da) were added to an LLDPE matrix containing 3% w/w Addiflex oxo-biodegradable additive (HES-W) and extruded and converted into films. Then the effect of presence of PH was investigated on microstructure, thermal and tensile behavior of polymer films before and after 6 weeks of ultra violet irradiation (UVR). Due to UVR, viscosity average molecular weight (Mv) of the sample without PH decreased from 9.6×104 to 4.6×103 Da and for the sample containing 3% w/w PH from 11.3×104 to 3.0×104 Da, also carbonyl index (CI) of the sample without PH increased from 0 to 28.7 while for the sample containing 3% w/w PH increased from 1.8 to 30.4. Moreover, differential scanning calorimetry (DSC) showed that crystallinity of the sample without PH increased from 34.4% to 36.9% and from 28.7% to 32.1% for the sample containing 3% w/w PH. Thermal gravimetric analysis (TGA) showed lower decomposition temperature for the samples containing PH. The elongation-at-break decreased from 723.0% to 88% for the sample without PH and from 410% to 10% for the sample containing PH. Atomic force microscopy (AFM) indicated smoother surfaces for samples containing 3% w/w PH before and after UVR. Although, the aforementioned results showed that the presence of limited amounts of PH in the LLDPE matrix deteriorated thermal and mechanical properties of the matrix, it hindered the oxo-biodegradablity of the matrix by opposing assimilation process perhaps due to high Mv and/or gelation.

Polyamide 6 / nitrile butadiene rubber / nanoclay (PA6/NBR/clay) nanocomposite has gathered wide acceptance in industry. Laser welding, as a fabrication method, is applied to welding of polymer nanocomposites. In this study, the input parameters (clay (Closite 30B) content, laser power, scan velocity and stand-off-distance) are varied to achieve the best responses (tensile strength of welds). Response surface methodology (RSM) is utilized to investigate the effect of input parameters on mechanical properties. Morphology and tensile properties of nanocomposites were observed with scan electron microscopy (SEM), transmission electron microscopy (TEM) and tensile test. The results demonstrated that increasing the clay content from 1 to 5%wt and stand-off-distance from 4 to 8 mm decreased tensile strength of welds about 15% and 5%, respectively. The tensile strength of PA6/NBR composite is 25.6, whereas the prediction models showed that under optimal conditions of laser power of 105 W, scan velocity of 300 mm/min and stand-off-distance of 4 mm, the maximum tensile strength of PA6/NBR nanocomposite with 1, 3 and 5 % nanoclay are 27.2 MPa, 27.6 MPa and 24.7 MPa, respectively. These tensile strengths are about 99, 89 and 73% of the strength of these nanocomposites before welding.

Polyurethane is a material that defines the word ‘versatile’. The structure property relationship of di-isocyanates and polyols is such that it provides ample variety and customization to the manufacturer. The properties of the polyurethane can range to extremes from soft touch coatings to rock hard rigid construction material. These mechanical, chtemical and biological properties and the ease of tailoring has produced a huge amount of interest in not only the scientific community but also in the concerned industries as well. The enhancement of the material can be done by manipulating the raw materials as well as adding different additives and nanomaterials as well. Proper modifications in the raw material can hence produce a polyurethane virtually suitable for every application. The study here throws light upon the basic chemistry of the building blocks of polyurethane and its recent advancements in applications in fields such as medical science, automobiles, coatings, adhesives, sealants, paints, textile, marine industry, wood composites and apparels.

Biosynthetically produced α-1,3-glucan dissolved in N,N-dimethyl acetamide/LiCl was allowed to react with lauric-, palmitic-, and stearic acid in presence of the activation agents p-toluenesulfonic acid chloride (TsCl), N,N′-carbonyldiimidazole (CDI), or the iminium chloride (ImCl) obtained from N,N-dimethyl formamide and oxalyl chloride. The highest degree of substitution (DS) of ester groups of 2.20 was obtained by reacting the glucan with 5 mol lauric acid and 5 mol ImCl per mole repeating unit within for 4 h at 100 °C. Formation of 6-deoxy-6-chloro moieties (as a known side reaction) is less pronounced in case of ImCl compared the use of TsCl for activation. The glucan esters melt except those synthesized with CDI as activation agent. The melting temperature is lower in case of higher DS, longer carboxylic acid, and lower molar mass. Products which do form a melt were shaped to films and could be used as basis for hot-melt adhesive to bond wood.

In this study, slurry polymerization kinetics of ethylene with TiCl4/Mg(OEt)2/AlR3 Ziegler-Natta catalysts in various conditions using the model of sum square error (SSE) (method I) and model of least square error (LSE) (Method II) was investigated. For this purpose the molecular weight distributions of the samples were deconvoluted to the minimum number of Flory type distributions where each represents a different active center type of Ziegler-Natta catalyst. The first method used to determine the leading apparent polymerization kinetic constants for each site in absence of hydrogen by simultaneously fitting the instantaneous polymerization rate, cumulative polymer yield, and molecular weight distribution measured for various samples with various conditions. Second method was used to determine all kinetics parameters such as initiation, propagation, termination and transfer to monomer reaction in absence and also in the presence of hydrogen. For the later, transfer to hydrogen also determined. The results showed that this simulation package is a powerful tool for design and scale up this kind of processes.

The melt drawability including melt strength (MS) and stretching ratio (V) of the neat low-density polyethylene (LDPE) and the LDPE composites loaded with a nanometer zinc oxide (nano-ZnO) were measured using a melt spinning method in capillary extruding temperature varied from 160 to 200 °C and within capillary flow rate range from 9 to 36 mm/s. It was found that the stretching ratio of the neat LDPE and the LDPE/nano-ZnO composites reduced with an increase of capillary flow rate while the V added with in a rise of capillary temperature. The melt strength of the neat LDPE and the LDPE/nano-ZnO composites enlarged with raising capillary flow speed; the MS reduced with an addition of capillary temperature. In addition, the dependence of the MS of the composites on the capillary temperature approximately accorded the Arrhenius expression.

High internal phase emulsions (HIPEs) are among complex biphasic fluids that expand on the traditional emulsion compositions, for instance, for the preparation of macroporous polymers by emulsion templating. The use of deep eutectic solvents (DESs) as the nonaqueous internal phase of HIPEs allows expanding the conditions at which polymerizations are typically carried out in aqueous HIPEs. Herein, the properties of polystyrene macroporous polymers were studied by polymerizing DES-in-oil HIPEs using choline chloride-based DESs as the internal phase. The effect of DESs’ composition – with amide, alcohol, and carboxylic acid as hydrogen bond donors – and the homogenization method used for the HIPE preparation – vortexing versus high-speed homogenizer – was studied. The stability and droplet size of HIPE precursor, as well as the macroporous structure and the mechanical properties of the synthesized polyHIPEs, are discussed.

The intelligent poly N,N-dimethylacrylamide hydrogel material system with high mechanical strength and the 3D printable property was prepared via in situ free radical polymerization under vacuum successfully. With the increase in nanofibrillated cellulose (NFC) content, stress and strain of hydrogels increased gradually. As the effective reinforcement, NFC enhanced the crosslinking density, which realized the controllable regulation of rheology behaviors including viscosity, storage modulus, and loss modulus of hydrogels. Combined with the swelling rate and the existence of the gel–sol transition point, a hydrogel with 10 mg/mL NFC was treated as the 3D printing ink of hydrogel actuators. Variation of printing parameters significantly affected self-driven deformations. The hydrogel actuators with 90°/0° and 45°/135° configurations owned bending and spiral deformations, respectively. Actuators with a larger length–width ratio owned a lower pitch value. The precise anisotropic swelling property of the printed bilayer structure was the self-driven deformation mechanism of hydrogel actuators, which provided material candidates for the preparation of soft robots and actuators.