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Designing polymer structures and polymer blends opens opportunities to improve the performance of plastics. Blending poly(butylene adipate-co-terephthalate) (PBAT) and polylactide (PLA) is a cost-effective approach to achieve a new sustainable material with complementary properties. This study aimed to predict the theoretical miscibility of PBAT/PLA blends at the molecular level. First, the basic properties and the structure of PBAT and PLA are introduced, respectively. Second, using the group contribution methods of van Krevelen and Hoy, the Hansen and Hildebrand solubility parameters of PBAT and PLA were calculated, and the effect of the molar ratio of the monomers in PBAT on the miscibility with PLA was predicted. Third, the dependence of the molecular weight on the blend miscibility was simulated using the solubility parameters and Flory–Huggins theory. Next, the glass transition temperature of miscible PBAT/PLA blends, estimated using the Fox equation, is shown graphically. According to the prediction and simulation, the blends with a number-average molecular weight of 30 kg/mol for each component were thermodynamically miscible at 296 K and 463 K with the possibility of spinodal decomposition at 296 K and 30% volume fraction of PBAT. This study contributes to the strategic synthesis of PBAT and the development of miscible PBAT/PLA blends.

This paper describes the use Excel’s Solver of Microsoft and desirability function for the determination of Hansen’s solubility parameters (HSPs). The Excel’s solver is powerful while at the same time being user-friendly and easy to comprehend. Results of HSPs for different polymers and oils were evaluated and compared with the results obtained by the use of other tools; no significant differences were found between the Microsoft Excel solution and either the professional program HSPiP or other software platform used by different authors. Improvements introduced in the Excel book developed by Steven Abbott for this purpose, by the inclusion of some restrictions and functions, allow simultaneously optimizing the diameter of the Hansen sphere together with the determination of Hansen’s parameters, so that a tool, available to professional and researcher, can be used for these determinations with a high degree of precision, using any of the nonlinear optimization algorithms available in the Solver add-in. Finally, it is illustrated how the use of programming in Excel VBA can lead to a friendly interface for these determinations.

In recent years there has been a growing interest in formulating solid dispersions, which purposes mainly include solubility enhancement, sustained drug release and taste masking. The most notable problem by these dispersions is drug-carrier (in)solubility. Here we focus on solubility parameters as a tool for predicting the solubility of a drug in certain carriers. Solubility parameters were determined in two different ways: solely by using calculation methods, and by experimental approaches. Six different calculation methods were applied in order to calculate the solubility parameters of the drug ibuprofen and several excipients. However, we were not able to do so in the case of ibuprofen lysinate, as calculation models for salts are still not defined. Therefore, the extended Hansen’s approach and inverse gas chromatography (IGC) were used for evaluating of solubility parameters for ibuprofen lysinate. The obtained values of the total solubility parameter did not differ much between the two methods: by the extended Hansen’s approach it was δt = 31.15 MPa0.5 and with IGC it was δt = 35.17 MPa0.5. However, the values of partial solubility parameters, i.e., δd, δp and δh, did differ from each other, what might be due to the complex behaviour of a salt in the presence of various solvents.

The compatibility between asphalt and nanosilica (nano-SiO 2 ) is critical to determine the performance of nano-SiO 2 –modified asphalt. However, a comprehensive understanding of the compatibility behavior and mechanism of asphalt components and nano-SiO 2 in the modified asphalt is still limited. In this study, the compatibility was revealed through molecular dynamics (MD) simulation. Virgin asphalt, nano-SiO 2 –modified asphalt, and oxidation aged asphalt models produced with the COMPASS force field; meanwhile, the proposed models were validated by comparisons with reference data. The compatibility of asphalt and nano-SiO 2 was analyzed by solubility and the Flory–Huggins parameters and interaction energy. Results show that the solubility parameters decreased with the increase of system temperature while increased with the asphalt’s oxidation level increase. Meanwhile, the compatibility of the asphaltene, resin, and aromatic components in asphalt is better than the compatibility with saturates, which may be due to saturates being volatile; however, the compatibility of the nano-SiO 2 and saturates is much better than those with asphaltene, resin, and aromatic components. The incorporation of nano-SiO 2 alleviates the volatilization of saturates. The present results provide insights into the understanding of the compatibility behavior and mechanism of nano-SiO 2 and asphalt components.

Based on the solubility parameter theory, the Hansen solubility parameters of various solvents were calculated and compared to predict the solubility of cellulose in various solvents, which illustrates the feasibility of Hansen solubility parameters to predict the solubility of cellulose in solvents. This paper aims to make a more accurate prediction in advance when finding suitable cellulose solvent system, and then to reduce the burden of cellulose solvent selection.

The equilibrium swelling test was employed to determine the swelling response of Nitrile Butadiene Rubber (NBR) with various acrylonitrile (ACN) contents, and the three-dimensional solubility parameter (HSP) and modified Flory–Huggins interaction parameter (χHSP) were used to establish the prediction model of the oil-resistant property. The results indicate that the energy difference (Ra) between NBR and solvents calculated by HSP values can be correlated with the swelling response qualitatively with an inversed “S-shape”, and high swelling response occurs at Ra < 8 MPa1/2 for NBR. For the purpose of establishing the prediction model, the new modified χHSP value has been calculated and fitted with the swelling response using exponential and logarithmic fittings, respectively. Two prediction models considering all the possible influencing factors have been obtained to determine the swelling response and oil resistance of NBR-based rubber products in bio-fuels, represented by the bio-diesel and IRM 903 test oil in this work. The swelling response of NBR can be evaluated precisely, and high swelling regions can be predicted and avoided in the new emerging fuels through the prediction models. Thus, the oil resistance of NBR-based rubber products, such as seals, holes and gaskets can be well predicted now.

The adsorption studies of contaminants on microplastics (MPs) collected from the marine environment are very hard to carry out mainly due to the difficulties associated with both to filtration of MPs and separation from biofilm and organic matrices. In this work, MPs were produced by a top-down protocol from polyethylene terephthalate (PET) bottles collected on the beach, thus already aged in the natural environment, and compared with engineered MPs obtained from PET pellets. Both types of MPs (size < 150 μm) were used to study the adsorption of amoxicillin, which is one of the most widely consumed antibiotics in the world and is found unchanged in the aquatic environment. The results of sorption kinetics and isotherm tests indicated that aged MPs absorbed a higher antibiotic content than unaged ones since the two kinds of microplastics had different specific surface areas. The experimental results were explained by analysing the thermodynamic affinity among amoxicillin and PET MPs and comparing it with several pharmaceuticals and other microplastics by evaluating Hansen’s solubility parameters (HSPs), which account for dispersive, polarizable and hydrogen bonding contributions to the overall cohesive energy of a compound. The possible interaction mechanism among amoxicillin and PET MPs, based on hydrogen bond interactions among the antibiotic and the ester groups of the polymer, was hypothesised. The results of adsorption tests demonstrated that PET MPs can be pollutant carriers with potential long-range transport in the aquatic environment.

Purpose This paper aims to discuss the successful 3D printing of styrene–ethylene–butylene–styrene (SEBS) block copolymers using solvent-cast 3D printing (SC-3DP) technique. Design/methodology/approach Three different Kraton grade SEBS block copolymers were used to prepare viscous polymer solutions (ink) in three different solvents, namely, toluene, cyclopentane and tetrahydrofuran. Hansen solubility parameters (HSPs) were taken into account to understand the solvent–polymer interactions. Ultraviolet–visible spectroscopy was used to analyze transmittance behavior of different inks. Printability of ink samples was compared in terms of shape retention capability, solvent evaporation and shear viscosity. Dimensional deviations in 3D-printed parts were evaluated in terms of percentage shrinkage. Surface morphology of 3D-printed parts was investigated by scanning electron microscope. In addition, mechanical properties and rheology of the SC-3D-printed SEBS samples were also investigated. Findings HSP analysis revealed toluene to be the most suitable solvent for SC-3DP. Cyclopentane showed a strong preferential solubility toward the ethylene–butylene block. Microscopic surface cracks were present on tetrahydrofuran ink-based 3D-printed samples. SC-3D-printed samples exhibited high elongation at break (up to 2,200%) and low tension set (up to 9%). Practical implications SC-3DP proves to be an effective fabrication route for complex SEBS parts overcoming the challenges associated with fused deposition modeling. Originality/value To the best of authors’ knowledge, this is the first report investigating the effect of different solvents on physicomechanical properties of SC-3D-printed SEBS block copolymer samples.

Surface esterification methods of cellulose nanocrystals (CNC) using acid anhydrides, acid chlorides, acid catalyzed carboxylic acids, and 1′1-carbonyldiimidazole (CDI) activated carboxylic acids were evaluated with acetyl-, hexanoyl-, dodecanoyl-, oleoyl-, and methacryloyl-functionalization. Their grafting efficiency was investigated using Fourier-transform infrared spectroscopy and 13 C solid state NMR spectroscopy. Acid anhydride and CDI were found to be the most applicable reagents to graft short and long chain aliphatic carbons, respectively. The preservation of structural morphology and crystallinity of grafted CNCs were confirmed using transmission electron microscopy and X-ray diffraction. The hydrophobicity of grafted CNCs was evaluated by dispersing them in organic solvents with different Hansen’s solubility parameters. The dispersibility of grafted CNCs in organic solvents was improved by using never-dried CNCs as source materials and keep CNCs wet in their washing solvents after grafting, thus increasing the solvency range to disperse CNCs.

Context To determine the miscibility of liquids at high temperatures using the concept of Hildebrand solubility parameter δ , the current practice is to examine the difference in δ between two liquids at room temperature, assuming that δ is not sensitive to temperature . However, such an assumption may not be valid for certain polymer blends and solutions. Therefore, a knowledge of the δ values of the liquids of interest at high temperatures is desirable. The determination of δ at high temperatures, especially for high-molecular-weight polymers, is impossible, as polymers have vapor pressures of zero. To this end, molecular dynamics (MD) simulations provide a practical means for determining δ over a wide range of temperatures. In this work, we study the temperature dependence of δ of five hydrocarbon polymers: polyethylene (PE), isotactic and atactic polypropylene ( i -PP and a -PP), polyisobutylene (PIB), and polyisoprene (PI) in five hydrocarbon solvents: n -pentane, n -hexane, n -dodecane, isobutene, and cyclohexane. The polymers are modeled as monodisperse chains with 100 repeat units. The average δ values of PE, i -PP, a -PP, PIB, and PI at 300 K are determined as 18.6, 14.9, 14.6, 14.3, and 16.4 MPa 1/2 , respectively, in a good agreement with experimental data. The δ values of these polymers at various temperatures are also determined. The temperature dependence of δ is fitted to two linear equations, one above and the other below the polymer’s glass transition temperature T g . The δ values are more sensitive to temperature at T  ≥  T g . The T g values of the polymers, determined based upon their specific volumes and δ values agree with the experiment qualitatively. The determination of the temperature dependence of δ has a great potential for industrial applications, such as determining miscibility, developing polymeric organogelators as flocculants and oil spill treating agents, and identifying potential solvents and ideal processing temperatures. Methods The MD simulations are performed using the GROMACS 2022.3 package with optimized potential for liquid simulations-all atom (OPLS-AA) force field parameters. All polymers are built as extended chains using CHARMM-GUI Polymer Builder. Graphical Abstract