Colloid and Polymer Science最新文献

The aim of this study is to explore a method for modifying waste brick powder (WBP) in order to reapply it to rubber products for effective resource recycling. Firstly, we use the auto polymerization of catechol/polyamine (CPA) on the surface of WBP to form a poly catechol/polyamine (PCPA) coating as an intermediate reaction platform. And then the macromolecular modifier, epoxy-functionalized elastomer (ethylene vinyl acetate-glycidyl methacrylate terpolymer) (EVMG), is further grafted onto the PCPA coating to prepare the WBP@EVMG hybrid materials. During the preparation of the WBP@EVMG hybrid materials, a ring-opening reaction between the amine group of PCPA and the epoxy group of EVMG occurs. The NR/WBP@EVMG composites are prepared by mechanical blending. The interfacial interactions between WBP@EVMG and NR are analyzed and verified in detail by dynamic mechanical analysis (DMA) and rubber process analyzer (RPA). It is shown that the modified NR/WBP composites show increased vulcanization rate and better mechanical properties, and the tensile strength, abrasion resistance, cracking strength, and wet slip resistance of NR/WBP@EVMG-15 are increased by 29%, 6%, 16%, and 11%, respectively, compared with that of NR/WBP composites, which provides a unique idea for the reuse of waste brick powder in rubber.

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This study investigates the assembly behaviour and physicochemical parameters of a drug-surfactant mixture comprising tetradecyltrimethylammonium bromide (TTAB) and promazine hydrochloride (PMZ) in water and aq. solutions of monohydroxy organic compounds (ethanol (EtOH), 1-propanol (1-PrOH), and 2-butanol (2-BuOH)) using conductometric method. The interaction between TTAB and PMZ has been characterized with the assessment of physicochemical quantities (critical micelle concentration (CMC), counter ion binding (β) and thermodynamic parameters (standard Gibbs energy (({Delta G}_{{varvec{m}}}^{{varvec{o}}})), enthalpy (({Delta H}_{{varvec{m}}}^{{varvec{o}}})), and entropy (({Delta S}_{{varvec{m}}}^{{varvec{o}}}))). The introduction of PMZ with TTAB surfactant resulted in a reduction of the CMC value and an augmentation of the magnitude of β. The inclusion of alcohols causes the delaying creation of micelles above 5% w/w of all alcohols employed. The enhancement of CMC values was acquired with the increase of temperature for TTAB and PMZ mixture. The micellization of the TTAB + PMZ system was obtained as spontaneous with ({-Delta G}_{{varvec{m}}}^{{varvec{o}}}) values. The observed values of ({Delta H}_{{varvec{m}}}^{0}) and ({Delta S}_{{varvec{m}}}^{0}) indicate that, the entropy plays the main roles in the assembly of TTAB + PMZ in aq. media, while the association is governed by the joint contribution from enthalpy and entropy in aq. alcohol solutions. The hydrophobic interaction is the key forces of interaction between TTAB and PMZ in water medium, whereas hydrophobic and ion-induced dipole are the probable interaction in aq. alcohol media. The thermodynamic of transfer and entropy enthalpy compensation parameters are computed and described with proper logics.

Spray drying is regarded as one of the most economical methods utilized in the production of liposome powder in industry. However, the poor reconstruction of the powder following rehydration imposes constraints on its potential utilization. In this study, three membrane stabilizers, Poloxamer 188 (P188), trehalose (Tre), and Tween 80 (T80) were selected due to their distinct localization behaviors, and their impact on the reconstruction of rehydrated liposomes was discussed. The mannitol-based spray-dried liposome powder with excellent reconstruction was successfully developed. After rehydrating the powder, the particle size (D_h) and polydispersion index (PDI) of mannitol-encapsulated liposome powder (Bla) significantly increase. Although adding leucine improved the dispersion of the powder (Bla/Leu), the increase in D_h and PDI after rehydration was more significant, changed from 172.79 nm and 0.075 for Bla to 459.97 nm and 0.291 for Bla/Leu, the micropolarity and hydrophobicity of membrane also increased, indicating a poorer reconstruction. The addition of extra membrane stabilizers enhanced the stability of the liposomes after rehydration. Specifically, the addition of T80 reduced the changes in D_h and PDI caused by leucine to 118.39 nm and 0.015, while the changes of ANS fluorescence intensity and I₁/I₃ to 178.66 a.u and 0.02. Raman spectroscopy revealed that the addition of membrane stabilizer greatly reduced the disorder of the acyl chain, especially the T80. It could be the embedding mode of T80 on liposomes and its excellent solubilization played the best role. It also showed the best stability in extreme environments such as acidity and ionic strength.

Graphical Abstract

A two-step synthetic method has been described to produce uniform magnetic polymer microspheres with carboxyl groups. The approach used proposes modification of polymer microspheres with magnetic nanoparticles, therefore allowing to expand range of sizes, shapes and surface group concentration of the resulting magnetic polymer microspheres. Synthesized magnetic polymer particles of 5.2 µm in size and carboxyl group concentration of 350 µmol/g react to magnetic fields, allowing them to be easily pulled from the solution after only 4 min of exposure to a permanent magnet. The desired size and morphology of the polymer particles were achieved by studying the influence of the swelling agent concentration, seed particle amount and size, inhibitor concentration, and initiator type.

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Abstract

The development of oil and gas resources in low-permeability reservoirs is being paid more and more attention. Moreover, oil and gas resources in low-permeability reservoirs are affluent, and the water cut of the medium permeability layer is so high that the injection capacity has decreased significantly. Therefore, it is of great importance to address the issues of injectability and enhance oil recovery in low-permeability reservoirs. Given the existing conditions of low permeability and high water cut in Daqing Oilfield, the synthesis of an in situ emulsified associative polymer (ISEPAM) is the focus of the research. The polymer was prepared by micellar polymerization, ensuring a molecular weight of 5 × 10⁶ Dalton. A series of experiments were conducted to investigate its dissolution filtration property, viscosifying, emulsification, anti-adsorption, conductivity, and oil displacement capacity. The experimental results show that ISEPAM has more significant properties than the polymeric surfactant (HB) used in Daqing Oilfield. The ISEPAM solution has significant filterability (filter factor is 1.1), viscosifying (38.66 mPa·s), emulsification (the water evolution rate of ISEPAM was only 4.4% for 60 min at 90% water cut), and good anti-adsorption property (after five adsorptions, still has a viscosity retention rate of 65%) in a specific concentration (1000 mg/L) and the field water in Daqing Oilfield (salinity is 4996.3 mg/L). The reason for this is due to the presence of dynamic reversible networks in the ISEPAM solution, and there are no cationic functional groups on the polymer chain. The conductivity of ISEPAM was tested using a homogeneous square core with 48.1 mD permeability, and the results show that the viscosity retention rate of the effluent can reach 90% and excellent injection property can be achieved. In the oil displacement test, ISEPAM presents excellent sweep efficiency and enhanced oil recovery by about 25% under 50 mD permeability. Under low permeability conditions, the ISEPAM exhibits better injectability and excellent oil displacement capacity. The related findings can provide an important idea and reference for the design and development of EOR polymers in the reservoirs with low permeability or high water cut.

In this paper, the aluminum gel with polymeric aluminum chloride (PAC) as the gelling agent and carbamide as a catalyst were investigated. The gelling regularities were studied, and its gelling performance was evaluated under high temperature and high salinity. The results showed that the basicity, mass fraction of PAC and carbamide, temperature, and salinity significantly influenced the formation of the gel. The gel exhibited exceptional thermal stability and gel strength under high temperature and salinity conditions. The results indicated that when the aluminum gel was prepared with 8 wt% PAC and 1 wt% carbamide and dissolved in brine with a salinity of 110,000 mg/L, the dehydration rate was less than 1 wt% after being aged for 180 days at 130 °C. Furthermore, the gel strength, elasticity, and yield stress increased with the rise in salinity. The experimental results showed that the aluminum gel is highly significant in plugging reservoirs with high temperature, high salinity, and low permeability.

Pectin gel and retinyl palmitate (RP)-loaded monoolein (MO) cubic phases were prepared by a melt-hydration method as a salt-responsive and anti-oxidative vehicle. The pectin gel was formed maximally when CaCl₂ concentration in aqueous pectin solution (0.25% to 2%) was 50 mM. The phase transition temperature (PTT) of the cubic phase, determined by differential scanning calorimetry (DSC), decreased from 58 to 46.9 ℃ as the RP content increased from 0 to 1.5%. The maximum release degree at 22 ℃ of a dye (amaranth) loaded in a cubic phase was about 15.9% and 51.3%, respectively, when the release medium was deionized water and PBS (10 mM, pH 7.4). An ion exchange between Na⁺ and Ca²⁺ seemed to cause the extensive release in the saline. The in vitro radical scavenging capability (RSC) of RP loaded in the cubic phase was proportional to the RP concentration and the RSC was substantially higher than that of free RP. The double bond of MO contained in the cubic phases was chemically stable during 6 months storage at 25 ℃ and 40 ℃, evidenced by ¹H NMR spectroscopy. The cubic phases maintained their integrity and retained their unique structure (the water channels winded by the lipid layers) under the same storage conditions.

The need for utilization of non-fossil fuel derived sources for polymer production is growing. In this study the terpenoids tetrahydrogeraniol, citronellol and nopol were modified with an esterification procedure using acryloyl chloride, forming terpenoid acrylates. The synthesised acrylates were used for the production of hierarchically porous polymers via high internal phase emulsion (HIPE) templating with emulsions consisting of an organic (monomer) phase and an aqueous phase with a volume fraction of 85%. The acrylate terpenoids in the organic phase were crosslinked with trimethylolpropane triacrylate (TMPTA) to form the polyHIPEs. A crosslinking degree of 5 and 10 mol% was used to investigate the feasibility of polyHIPE production. While both crosslinking degrees enabled the synthesis of polymers, only the 10 mol% crosslinking yielded the typical interconnected porous cellular topology. The average primary pore diameter in the case of the tetrahydrogeraniol acrylate and citronellyl acrylate was 15.6 and 16.5 μm, respectively, while the average primary pore diameter in the case of nopol acrylate was 5.6 μm.

The membrane emulsification (ME) method is a highly promising technology that utilizes synthetic microporous membranes to produce high-quality, droplet-size controlled dispersions and colloidal particles at low shear stress and low energy input. This technology has enabled the preparation of microspheres, microcarriers, microcapsules, polymers, and gel microbeads with tunable properties, which find extensive applications in drug delivery systems and the formulation of novel products in the cosmetics, chemical, pharmaceutical, and food industries. Despite its potential for use in various processes, the adoption of ME technology has been limited by its low production throughput. To overcome this limitation, numerous approaches have been developed over the years, including new ME methodologies, fabrication of new membranes, use of new additives and formulations, and optimization of process conditions. This review comprehensively explores these approaches and highlights the major process parameters that control production throughput and their relationship to membrane and ingredient properties. While a single technique may not be universally applicable in all fields, utilizing multiple strategies can significantly enhance the production throughput of the ME method. A thorough understanding of the ingredients’ nature, final product requirements, and process limitations can aid in determining the most suitable strategies to employ in different fields of application.

Adsorption and photocatalytic decolorization methods were used to remove Reactive Orange 16 dye from textile wastewater by using ethyleneglycoldimethacrylate and 1-vinyl-1,2,4-triazole, m-poly(EGDMA-VTA)-TiO₂ polymer composite particles with magnetic synthesized by suspension polymerization. The characterization of the synthesized m-poly(EGDMA-VTA)-TiO₂ particules were carried out by using XRD, FTIR, SEM–EDS-elemental mapping, ESR, and BET analyses. Both adsorption and photocatalytic decolorization processes of RO16 dye were applied to the polymer particles. The effects of solution pH, amount of adsorbent, initial dye concentration, temperature, and time on the adsorption capacity were investigated. The removal of R016 dye reached a maximum at pH 3. Dye substance removal decreased due to increasing temperature and adsorbent amount. As a result of experimental studies, the adsorption of RO16 dye was explained by the Langmuir isotherm, while its kinetics was stated by a pseudo-second-order mechanism. Additionally, thermodynamic functions (ΔH^o, ΔG^o, and ΔS^o) have been determined. At the end of adsorption, the decolorization kinetics were elucidated by examining the adsorbent amount, time, and dye concentration parameters for the photocatalytic decolorization of non-adsorbed dyes. It was determined that the photocatalytic activity was highest at low dye concentration and high photocatalyst content. Additionally, it was determined that decolorization kinetics studies were compatible with the Langmuir–Hinshelwood model.