Emulsion Polymerization Research Articles

A comprehensive study on the application properties of different soft, hard, and functional monomers to polyacrylate emulsion and water‐based inks

AbstractThe urge to protect the deteriorating ecosystem is compelling us to develop environmental‐friendly materials. In this paper, three different kinds of waterborne polyacrylate emulsions were synthesized with different hard, soft and hydroxyl‐containing functional monomers by semi‐continuous seed emulsion polymerization. Moreover, the influences of different monomers on the performances such as viscosity, adhesion, surface tension, particle size, stability, and contact angle were also investigated. Attractively, conclusions were deduced that with the growth of the monomer's alkyl chain length, the viscosity gradually increases and the surface tension gradually decreases. On the other hand, different functional monomers also have effect on the properties of the synthesized acrylic emulsions. Then the synthesized water‐based acrylic emulsions were used as binders for water‐based inks, the adhesion as well as initial dryness were tested and the recipe for water‐based ink with better performances was selected out. Our work maybe ignites a spark for the designation of acrylic emulsions for water‐based inks binders.

Cerium Oxide‐Armored Composite Latex Particles by Visible Light Emulsion Photopolymerization: From Synthesis to Film Properties

AbstractCerium dioxide (CeO2) has huge potential in many applications ranging from biochemical engineering to the coating industry. Here, the first example of visible light photo‐mediated Pickering emulsion polymerization of (meth)acrylate monomers is reported using CeO2 nanoparticles (NPs) as solid stabilizer. A ω,ω′−dicarboxylic acid diphenyl disulfide photoinitiator is anchored on the surface of the CeO2 NPs and used to initiate the emulsion polymerization of methyl methacrylate (MMA) and of MMA/n‐butyl acrylate (MMA/BA) under visible light leading to CeO2‐armored latexes. Radicals generated upon light irradiation trigger the formation of polymer chains chemically attached to the CeO2 NPs, promoting their subsequent adsorption on the latex surface. The composite films obtained from the CeO2‐armored P(MMA‐co‐BA) latexes exhibit a unique honeycomb nanostructure with the nanoceria located in the walls giving the materials excellent mechanical, anti‐UV, and photocatalytic properties.

Interfacial Pickering Emulsion Polycondensation for Degradable Nanocomposites.

Pickering emulsion polymerization is a practical method to fabricate functional composite materials. However, most reported systems proceed homogeneously within the stabilized monomer phase and create nondegradable chemical bonds. Here, interfacial Pickering emulsion polycondensation between aromatic aldehydes and polymercaptans is developed using sustainable cellulose nanoparticles as the stabilizer. When sulfonated cellulose nanocrystals (S-CNCs) were utilized, they also catalyzed the polycondensation to produce the oxidatively degradable S,S-acetal groups on the polymer chains. The influence of monomer and cellulose structures on the polymerization behavior and composite properties were compared.

Sustainable barrier coatings for paperboard packaging: Effect of VeoVa-10 on 2-EHA and MMA containing water-based emulsions

Developing environmentally benign barrier coatings may provide a sustainable alternative to the packaging sector and facilitate minimizing the consumption of single-use plastics in packaging. The synthesis of seven different water-based (W/B) emulsions was achieved via seeded emulsion polymerization using 2-Ethylhexylacrylate (2-EHA), methyl methacrylate (MMA), and a varying amount of vinyl ester of Versatic™ acid 10 (VeoVa-10) to impart the hydrophobic properties. Potassium persulfate (K2S2O8) was used as an initiator. Antifoaming agent and biocide were also added to improve the application and shelf-life of these coatings. The coatings were evaluated by conducting various analytical tests, including pH measurement, viscosity assessment, determination of solid content, measurement of drying time, evaluation of gloss, water absorption testing using Cobb's Test, and assessment of oil and grease resistance via the Kit Test. The coatings were also analyzed using advanced characterization techniques, including Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Zetasizer Nano ZS, and contact angle analysis. The results indicated that as the amount of VeoVa-10 increases in barrier coatings, the coated paperboard demonstrated improved moisture and oil/grease resistance compared to the control paperboard (uncoated). Furthermore, the coatings were also applied on paperboard trays and stored at 0 °C and 90 °C to confirm their practical usefulness, a careful examination after an hour showed no leakage/seepage of hot and cold water through the coated trays, unlike the uncoated ones. Barrier coatings offer sustainable and eco-friendly options that could positively impact the packaging industry, helping reduce environmental footprints while enhancing packaging performance.

Optimisation and Composition of the Recycled Cold Mix with a High Content of Waste Materials

This research focuses on a mineral–cement mixture containing bitumen emulsion, designed for cold recycling procedures, the formulation of which includes 80% (m/m) of waste material. Deep cold recycling technology from the MCE mixture guarantees the implementation of a sustainable development policy in the field of road construction. The utilised waste materials include 50% (m/m) reclaimed asphalt pavement (RAP) from damaged asphalt layers and 30% (m/m) recycled aggregate (RA) sourced from the substructure. In order to assess the possibility of using a significant amount of waste materials in the composition of the mineral–cement–emulsion (MCE) mixture, it is necessary to optimise the MCE mix. Optimisation was carried out with respect to the quantity and type of binding agents, such as Portland cement (CEM), bitumen emulsion (EMU), and redispersible polymer powder (RPP). The examination of the impact of the binding agents on the physico-mechanical characteristics of the MCE blend was performed using a Box–Behnken trivalent fractional design. This method has not been used before to optimise MCE mixture composition. This is a novelty in predicting MCE mixture properties. Examinations of the physical properties, mechanical properties, resistance to the effects of climatic factors, and stiffness modulus were conducted on Marshall samples prepared in laboratory settings. Mathematical models determining the variability of the attributes under analysis in correlation with the quantity of the binding agents were determined for the properties under investigation. The MCE mixture composition was optimised through the acquired mathematical models describing the physico-mechanical characteristics, resistance to climatic factors, and rigidity modulus. The optimisation was carried out through the generalised utility function UIII. The optimisation resulted in indicating the proportional percentages of the binders, enabling the assurance of the required properties of the cold recycled mix while utilising the maximum quantity of waste materials.

Achieving optimum balance between mechanical properties and gloss of acrylonitrile–styrene–acrylate resin through control of rubber particle size distribution

AbstractPreparation of acrylonitrile–styrene–acrylate (ASA) with high gloss and superior impact properties is still challenging. Here, we developed a new strategy for the preparation of ASA resins by a selective redox initiation method based on a semi‐continuous emulsion polymerization technique. A series of ASA core‐shell impact modifiers were firstly obtained by grafting styrene (St) and acrylonitrile (AN) onto poly(n‐butyl acrylate) (PBA) seeded latexes of different sizes. The ASA core‐shell impact modifier was then used to toughen the styrene–acrylonitrile copolymer (SAN). The synergistic effects between the single particle size of the rubber phase and different particle sizes were systematically investigated, and the mechanical properties of SAN‐toughened resins at various particle sizes of the rubber phase were analyzed. The results revealed that toughened SAN with small particle sizes possessed better gloss, and the impact strength of the doped small‐particle toughened SAN was much higher than that of the single particle size toughened SAN. The ASA graft powders synthesized from large particle PBA (particle size 316 nm) and small particle PBA (particle size 99 nm), respectively, were mixed at a 50/50 ratio and blended with SAN resin, a gloss level reaching 95, and an impact performance of 275 J/m values almost twice those of a single particle size toughened SAN.Highlights Acrylonitrile–styrene–acrylate resins with an impact strength of 275 J/m and gloss of 95 were prepared. The balance between mechanical properties and gloss of acrylonitrile–styrene–acrylate resin was obtained. Polymerization was initiated at low temperature.

Thermally Regulated Flocculation-Coalescence Process by Temperature-Responsive Cationic Polymeric Surfactant for Enhanced Crude Oil-Water Separation

Polymeric surfactants play a crucial role in the flocculation-assisted coalescence process due to their unique bridging effect. However, the steric hindrance induced by their large molecules severely impedes the coalescence of oil droplets. Herein, temperature-responsive polymeric surfactants (quaternary ammonium chitosan-g-PNIPAM, Q-g-PN) with thermally-modulated structure were designed by integrating thermal responsive moieties onto cationic chitosan. The as-prepared Q-g-PN exhibited enhanced oil-water separation efficiency through a thermally regulated flocculation-coalescence process. At low temperatures, the thermal-responsive Q-g-PN remains in a flexible hydrophilic extended state, facilitating the flocculation of dispersed oil droplets through bridging via electrostatic interaction. At high temperatures, the Q-g-PN structure collapses into a hydrophobic coil state, reducing steric hindrance and enhancing hydrogen bonding to asphaltenes, thus effectively promoting oil droplet coalescence. Bottle tests demonstrated that the demulsification performance of Q-g-PN could reach up to 94% with the Q-g-PN concentration only of 0.001wt% via the proposed temperature-regulated flocculation-coalescence process, which was further confirmed by investigating oil droplet behavior and phase transition of Q-g-PN during through molecular dynamic (MD) simulation of the reaction process. This work presents new insights into enhancing oil-water separation efficiency by regulating the flocculation-coalescence process through precise modulation of the molecular interactions between polymer surfactants and emulsion droplets.

Damping and acoustic properties of nanosilica filled poly(styrene-acrylate) interpenetrating polymer networks (IPNs): Effect of nanocomposite preparation method

Research on noise pollution reduction has focused on utilizing damping coatings and polymer nanocomposites to enhance sound absorption. Nanosilica/poly(styrene-acrylate) nanocomposites as a water-based coating were prepared through in-situ emulsion polymerization and direct mixing methods at varying concentrations of 1, 2, and 3 wt% of nanosilica. Fourier transform infrared (FTIR) spectroscopy revealed that the inclusion of surfactant-containing micelles and a more extended synthesis period in the in-situ synthesis technique enhanced the interaction between silica nanoparticles and polymer chains. Dynamic light scattering (DLS) analysis showed a unimodal distribution and an acceptable range of polydispersity index (PDI) for neat and nanocomposite latexes. The addition of silica nanoparticles enhanced the stability of latex particles, especially evident in the direct mixing method. The field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) images confirmed the better dispersion of nanoparticles within the polymer matrix in the in-situ method. The addition of nanosilica resulted in a significant increase in pseudoplastic behavior and viscosity, notably in the in-situ synthesis. In both the in-situ synthesis and direct mixing techniques, the addition of 1 wt% of nanosilica resulted in an increase in the damping factor of nanocomposite films to about 2. However, when the nanosilica content was further increased to 3 wt%, the damping factor decreased. Acoustic tests demonstrated improved sound absorption with silica nanoparticles, yielding noise reduction coefficient (NRC) values of 0.49 and 0.46 for in-situ synthesis and direct mixing. The direct mixing method notably enhanced tensile properties at all nanoparticle content levels. Dried nanocomposite films exhibited superior UV-blocking capabilities compared to neat polymer films.

Design of dinuclear osmium complex doped antifouling cellulose nanoparticles for targeting and dual photodynamic/photothermal therapy under near infrared irradiation

Transition metal-ligand has been explored in the treatment of tumors in photodynamic theray (PDT) or photothermal therapy (PTT) and Osmium complex attracts attentration due to its lower toxicity and longer absorption wavelength. However, there was no report about binuclear Os complex for combined therapy of PDT and PTT which could have a synergistic effect and improve the effectiveness. Herein, we synthesis of mono/dinuclear Os complexes (OsY1, OsY2) with dual PDT/PTT capabilities under a single near-infrared (NIR) excitation wavelength. These features arise from the large π-conjugated structure of our dinuclear Os complex coupled with efficient metal-to-ligand charge transfer, which bring in ultralow energy gaps of 0.733 eV and 0.308 eV for OsY1 and OsY2, respectively. Furthermore, we prepared the Osmium complex-doped, aptamer-conjugated cellulose NPs via the emulsion polymerization method. These NPs exhibit a notable ability to target mitochondria and posse a “protein corona-free” status, showing much higher efficiency in tumor ablation (76 %) than the commercialized indocyanine green (ICG) doped cellulose NPs (24 %) under 808 nm irradiation. Consequently, our designed mono/dinuclear Os complex, featuring a single-molecule dual PDT/PTT effect within doped antifouling NPs, holds promise for potential applications in cancer therapy.

Colloidal stability of styrene-acrylic latexes using anionic and nonionic polymerizable surfactants by seeded emulsion polymerization for waterborne paints

Colloidal stability of styrene-acrylic latexes using anionic and nonionic polymerizable surfactants by seeded emulsion polymerization for waterborne paints

POSSIBILITIES OF SYNTHESIS OF UNCHARGED STABLE LATEX PARTICLES FOR IMMUNOANALYSIS

Objective: The objective of this study is to find a method for synthesizing uncharged polystyrene latex particles whose surface can be easily modified. Theoretical basis: The main method of latex synthesis is emulsion polymerization. Latexes for a specific purpose can be obtained by polymerization in heterogeneous monomer-water systems, without the use of emulsifiers, both with intensive mixing of the system and under static conditions. In this work, polymerization was carried out without the use of emulsifiers in a static monomer-water system. Method: To achieve the set goal, the possibility of obtaining latex particles using a hydrophobic initiator - ditrile of azoisobutyric acid - was investigated by carrying out polymerization in a diffusion mode in a three-phase system monomer - water - initiator. Results and discussion: The results of the study showed that the latex obtained in the three-phase system is stable. It is assumed that the stability is due to the presence of hydroxyl end groups groups of polymer molecules on the surface of the latex particles, which are formed as a result of the reaction of the initiator with water and initiate polymerization. The synthesized latexes retained stability for a year. Practical value: Latexes can be used in all those areas of science and technology where the absence of a charge on the surface of latex particles is required. Originality/value: The originality of the work lies in the fundamental simplicity of the synthesis and the unambiguity of the results obtained.

Fully Atom-Efficient Solvent-Mediated Biopolymer Manufacturing: A Base Case Illustrated with Macromolecular Surfactants Tailored to Stable Polymer-Water Interfaces.

This work introduces a novel 1-pot, 0-waste, 0-VOC methodology for synthesizing polymeric surfactants using acrylated epoxidized soybean oil and acrylated glycerol as primary monomers. These macromolecular surfactants are synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization, allowing for tunable hydrophilic-lipophilic balance (HLB) and ionic properties. We characterize the copolymers' chemical composition and surface-active properties, and evaluate their effectiveness in forming and stabilizing emulsions of semiepoxidized soybean oil and poly(acrylated epoxidized high oleic soybean oil). Comprehensive analyses, including gel permeation chromatography, nuclear magnetic resonance spectroscopy, dynamic light scattering, particle size distribution, zeta potential, and critical micelle concentration, provide detailed insights into the copolymers and the emulsions they form. The results demonstrate that the RAFT-polymerized surfactants offer long-lasting stability and effectively disperse both common oil-in-water emulsions and highly viscous and hydrophobic polymer latexes. These surfactants outperform traditional small molecule surfactants by reducing particle size and preventing phase separation, even over extended storage periods. Stable polymer-water interfaces are achieved through HLB control, tailored by monomer composition, and the final product requires no additional purification since polymerization occurs in liquid surfactants. While small molecules contribute to rapid micelle formation, the polymeric components enhance long-term stability through steric repulsion and slower dynamics. This method enables even the emulsification of polymers with submicron particle size, which ordinarily requires emulsion polymerization. Integrating biobased polymeric surfactants with advanced polymer processing techniques opens new possibilities for transforming highly hydrophobic polymers into latexes, facilitating downstream applications. This innovation enhances the environmental sustainability of surfactant production and broadens the potential for polymer emulsification technologies. Additionally, the integrated solution-processing approach demonstrated here can be applied to other emerging polymers, where judiciously selected nonvolatile solvents facilitate the polymerization and play a role in the final application.

Kinetic Investigation of the Emulsion Polymerization of Vinylidene Fluoride

AbstractPoly(vinylidene fluoride) (PVDF) is among the most produced fluoropolymers, second only to polytetrafluoroethylene. Despite its popularity, the complex microstructural properties achieved during the polymerization are not well documented in the literature. In particular, available models only track the chain length distribution of the polymer, while neglecting the distribution of other important properties, affecting the final behavior of the product. In this work, a 2D kinetic model, evaluating not only the chain length but also the number of terminal double bonds (TDBs) per chain, is developed. The numerical solution of the model is achieved by fractionating the population of polymer chains into classes with a specific number of TDBs and using the method of moments for each class. The model results are compared with experimental evidences for the amount of produced polymer, moles of main chain‐ends, number, and weight average molecular weight as well as full molecular weight distribution. Based on this comparison, kinetic parameters are estimated by optimization using genetic algorithm. The model reliability is finally verified using additional experimental data at different temperatures and amounts of initiator.

Hyperbranched Organosilicon Surfactants as Emulsifiers for the Emulsion Polymerization of Methyl Methacrylate

This report is devoted to the investigation of the emulsion polymerization of methyl methacrylate in the presence of PEGylated hyperbranched polymethylethoxysiloxane as an emulsifier. It is shown that its use in the amount of 1–5 wt % affords stable 25–50% poly(methyl methacrylate) dispersions with the controlled particle sizes from 300 to 800 nm and a narrow particle size distribution.

Monomer Transport via Collision in Emulsion Polymerization

AbstractOne of the questions still remaining regarding emulsion polymerization is the issue of mass transfer versus reaction limitation since, by its nature, emulsion polymerization requires monomer transport across an aqueous phase. This question is brought into focus lately by the growing use of miniemulsion polymerization in which the monomer transport step is much less important. This paper will explore the possible rate of monomer transport via collision and ratio this to the maximum rate of polymerization using the Damkohler analysis formality. Results indicate that systems relying on monomer transport by collision will be almost universally monomer‐transport‐limited, thus exhibiting lower‐than‐expected rates of polymerizations.

Synergistic Radical Taming by Concurrent Degenerative Transfer and Atom Transfer Radical Polymerization in Emulsion

Synergistic Radical Taming by Concurrent Degenerative Transfer and Atom Transfer Radical Polymerization in Emulsion

Advancing Sustainability: Geraniol-Enhanced Waterborne Acrylic Pressure-Sensitive Adhesives without Chemical Modification.

The escalating global emphasis on sustainability, coupled with stringent regulatory frameworks, has spurred the quest for environmentally viable alternatives to petroleum-derived materials. Within this context, the adhesives industry has been actively seeking renewable options and eco-friendly synthesis pathways. This study introduces geraniol, a monoterpenoid alcohol, in its unmodified form, as a key component in the production of waterborne pressure-sensitive adhesives (PSAs) based on acrylic latex through emulsion polymerization. Multiple formulations were developed at varying reaction times. The adhesives underwent comprehensive chemical characterization employing techniques such as Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Nuclear Magnetic Resonance (NMR), Gel Permeation Chromatography (GPC), and dynamic light scattering (DLS). The viscosities of the formulations were measured between 4000 and 5000 cP. Adhesion tests showed peel strength values of 0.52 N/mm on cardboard and 0.32 N/mm on painted steel for the geraniol-based formulations. The results demonstrate the potential for geraniol-based PSAs to offer a sustainable alternative to petroleum-derived adhesives, with promising thermal and adhesive properties.

Distributed optical fiber sensors for real-time tracking of fouling buildup for tubular continuous polymerization reactors

Early online fouling detection is expected to be a real step forward in the operation of continuous tubular reactors. As an online technology, the Rayleigh backscatter based Distributed Optical Fiber Sensor (DOFS) technology was evaluated with respect to temperature measurement resolution, reproducibility and the best online calibration method. Different coatings and terminations were characterized for emulsion polymerization reactors. Commercially available sensors with acrylate primary coatings, dual acrylate coatings, and polyimide coatings were all compared with each other. It is shown that the presence of a secondary coating significantly alters sensor behaviour. Sensors with only a primary coating showed a temperature resolution of 0.1 °C. Online calibration for temperature readout was carried out and validation tested on segments of fiber integrated in a 3D-printed reactor channel (diameter 1.5 mm). Acrylate coated sensors showed a deviation of 20 % for the calibration coefficients when inside the reactor channel compared to the online calibration, leading to errors in temperature measurement. Polyimide coated sensors showed a deviation of just 0.6 % in this validation test, demonstrating good capabilities for online calibration with accurate temperature measurements. The possibility of spatial and temporal monitoring of fouling buildup through a heat exchanging wall equipped with DOFS was evaluated.

Research and Evaluation of a Nanometer Plugging Agent for Shale Gas Horizontal Wells.

Due to the low permeability of shales, drilling fluid filtrate is very likely to intrude into the formation along the nanomicron pore joints of shale, leading to microfracture expansion and causing a well wall destabilization phenomenon. Based on the characteristics of the formation shale, a new nano plugging agent, styrene (St)/2-acrylamido-2-methylpropanesulfonic acid (AMPS)/ethyl acrylate (EA), was synthesized by emulsion polymerization using St, EA, and AMPS as reaction monomers. The analysis results using infrared spectroscopy and transmission electron microscopy showed that the product met the expected design. The particle size of the nano plugging agent St/AMPS/EA was mainly concentrated in the range of 50-130 nm. Thermogravimetric analysis revealed that the initial thermal decomposition temperature of St/AMPS/EA is 363.8 °C, indicating strong thermal stability. At a 3% concentration, the permeability of the mud cake decreased by 87.35%, and the maximum differential stress of the shale increased from 141.7 to 174.4 MPa. Stability analysis showed that the plugging agent maintained good plugging performance under various pH values and salinity conditions with fluid loss consistently around 3.2 mm. This nano plugging agent significantly improves wellbore stability, making it suitable for drilling in the Longmaxi Formation shale with developed microfractures, and provides valuable insights for similar formations.

Synthesis of polymeric nanoparticles with different functionalities to produce new biocatalysts

AbstractThis study aimed to synthesize functionalized nanosupports via emulsion polymerization to develop new promising nanobiocatalyts via enzyme immobilizations. The co‐monomers methyl methacrylate, divinylbenzene and the epoxy monomer glycidyl methacrylate (GMA) were used. The performance of the nanobiocatlysts was evaluated in hydrolysis and esterification reactions after the immobilization of lipase B from Candida antarctica (CAL B). Firstly, the nanosupports functionalized in situ with 25% and 50% w/w of GMA were successfully synthesized. In esterification reactions, the nanobiocatalysts containing 25% (w/w) of GMA were more active, achieving 254 U.g−1, or an enzyme activity per area of 2.8 U.m−2; such value was higher than the one obtained when the commercial matrix Octadecyl Sepabeads was used (328 U.g−1, 2.4 U.m−2). Such results point out that there is an optimum concentration of GMA epoxide groups that should be incorporated into the supports. The greater enzymatic activity obtained for 25% of GMA nanobiocatalyst was achieved not only because of their textural properties, but also due to a favorable interaction between the epoxide groups and CAL B. These results highlight the potential use of the heterofunctional matrices for the synthesis of new market‐competitive biocatalysts.