Seeded Emulsion Polymerization Research Articles

Preparation and characterization of long carbon chain based polyacrylate latexes and their pressure sensitive adhesive application

Aqueous emulsion homo- and co-polymerization of lauryl methacrylate (LMA), a strong hydrophobic monomer with long carbon chain, is quite challenging. In this study, a long carbon chain emulsifier N-390 was used as the primary emulsifier to facilitate the emulsion copolymerization of LMA with other acrylate monomers through the mutual hydrophobic interaction between N-390 and LMA, and ultimately polyacrylate latex pressure sensitive adhesives modified by LMA via pre-emulsified semi-continuous seeded emulsion polymerization process were synthesized. The effects of LMA on the resulting latex and PSA properties was comprehensively examined. Both FTIR and 1H NMR spectra indicated that LMA has been successfully introduced into copolymer chain with the aid of long carbon chain emulsifier N-390. The results also showed that the introduction of LMA will contribute to decrease in particle size and zeta potential, while increase viscosity and gel content of the acrylate PSA latex. Moreover, as the LMA content increased, the latex PSA films demonstrated gradual improvements in both water resistance and thermal stability. Finally, for the long carbon chains adhesive film, the shear strength was improved greatly while at the sacrifice of loop tack and peel strength, when compared to counterparts without LMA.

Preparation of Poly(Butadiene–Styrene–Vinyl Pyridine)/Poly(Acrylonitrile–Butadiene) Core–Shell Nanoparticles by Intermittent Seeded Emulsion Polymerization and Their Catalytic Latex Hydrogenation

Preparation of Poly(Butadiene–Styrene–Vinyl Pyridine)/Poly(Acrylonitrile–Butadiene) Core–Shell Nanoparticles by Intermittent Seeded Emulsion Polymerization and Their Catalytic Latex Hydrogenation

Organelle-like water-borne curcumin nanoparticles with smart fluorescence for anti-counterfeiting and food quality monitoring

Current fluorescent labels are often expensive and environmentally unfriendly and tend to lose their fluorescence when combined with dry and hydrophilic substrates because of their hydrophobic nature. Thus, the development of environmentally friendly, low-cost, and scalable fluorescent materials is still highly desirable but significantly challenging, especially for anti-counterfeiting and food quality monitoring. In this study, highly fluorescent nanoparticles were prepared by mimicking organelles and using natural and sustainable curcumin as a fluorescent component. The preparation process was easily scalable via traditional seeded emulsion polymerization methods and green without using additional organic solvents. The resulting curcumin-based fluorescent nanoparticles (CFNs) were well dispersed in water, offering smart fluorescence in water-based environments or a dried polymer coating. In particular, CFNs-based coatings could be used for effective smart anti-counterfeiting and food quality monitoring. The proposed strategies may inspire the design of novel, green, and sustainable smart fluorescent materials/coatings for applications in anti-counterfeiting, smart food tags and labels, and visual sensing systems.

Synthesis and characterization of organosilicon functionalized water-based polyvinylidene chloride emulsion with core-shell structure

The outstanding barrier performance of polyvinylidene chloride (PVDC) has attracted widespread attention. In this work, a series of organosilicon functionalized water-based PVDC emulsions with core-shell structure are synthesized by seed emulsion polymerization using vinylidene chloride (VDC), methyl acrylate (MA), isooctyl acrylate (EHA) as core and vinylidene chloride (VDC), methyl acrylate (MA) as shell. Vinyl-terminated polydimethylsiloxanes (VT-PDMS) are introduced into the core-shell as modifier. The properties of PVDC emulsions and films modified with VT-PDMS are investigated. On the one hand, when VT-PDMS is properly incorporated into the core-shell particles, the Si-O bonds in VT-PDMS are dissociated, which further forms a cross-networking structure, thereby enhances the adhesion of PVDC film to the substrate. The barrier performance of the film is also improved by a small amount of cross network structure. On the other hand, the addition of VT-PDMS leads to the phenomenon of thin film shrinkage, which further enhances the barrier performance of PVDC. All results indicate that the best comprehensive performance is achieved when the VT-PDMS content in the PVDC core is 2 wt%, the adhesion can be increased to 0.527 MPa, the oxygen transmittance is 5.68 cc/m2·24 hr, and the actual time of water barrier after coating starch-based tableware is over 12 hours. This provides an effective line of thinking for the further application of PVDC barrier film in the field of environmental protection food packaging.

Research on Nano-ZnO/fluorine Polyacrylate Linen Fabric Finishing Agent

ABSTRACT With nano-ZnO, methyl methacrylate (MMA), ethyl acrylate (EA), and dodecafluoroheptyl methacrylate (DFMA) as reaction monomers, potassium persulfate as initiator, nano-ZnO/fluorine polyacrylate linen fabric finishing agent was prepared by semi-continuous seed emulsion polymerization to improve the hydrophobicity and anti-fouling performance of linen fabric. The structure and properties of the film and the finished fabric were characterized and analyzed by1HNMR, FT-IR, and TG. The results showed that the nano-ZnO/fluorine emulsion was successfully prepared with a particle size of about 46 nm, which was combined with linen. The contact angle of the finished linen fabric to water was 130.33°, which indicated that the finished linen fabric had good hydrophobicity. Meanwhile, the anti-fouling performance of the finished linen fabric was also improved. The introduction of nano-ZnO and organic fluorine in turn made linen fabric had the properties of the heat-resistant stability, UV resistance, antibacterial properties, and yellowing resistance.

Chemical, thermal and film properties of metal cross-linking fluorinated polyacrylate colloid prepared via semi-continuous seeded emulsion polymerization

The metal cross-linking fluorinated polyacrylate colloid has a high cross-linking density, high transparency, high heat resistance and hydrophobicity. In this paper, the metal cross-linking fluorinated polyacrylate colloid is synthesized via the semi-continuous seeded emulsion polymerization technology, which uses the self-made magnesium acrylate, calcium acrylate and zinc acrylate as metal crosslinker and dodecafluoroheptyl methacrylate as a fluorine monomer. In this study, the ablation effect of the metal ions is weakened by the increased amount of environmentally friendly and polymerizable anion emulsifier DNS-86. The demulsification phenomenon of emulsion is successfully overcome through destroying the double layer structure of micelles or colloid particles by polyvalent metal ions. The colloidal particle size is smaller and the particle size distribution of the colloid is more uniform. Colloidal film has a good hydrophobicity and the glass transition temperature and the thermal decomposition temperature are high.

Anisotropic Magnetic Polymeric Particles with a Controllable Structure via Seeded Emulsion Polymerization.

Magnetic polymer composites have been widely utilized in potential applications in material science, such as reduction of dyes, immunodiagnostics, biomedicals, and magnetically controllable photonic crystals owing to large surface areas, fast separation, and recyclable performance. In this work, anisotropic magnetic particles were prepared by seeded emulsion polymerization, with morphologies of "Fe3O4-shell", "hemisphere-like", "raspberry-like", "multiple lobes-like", and "sandwich-like". Poly(styrene/divinylbenzene/mono-2-(methacryloxy)ethyl succinate)@ Fe3O4 (P(St/DVB/MMES)@Fe3O4) were the seed microspheres, and P(St/DVB/MMES)@Fe3O4@polymer particles are achieved by seeded emulsion polymerizations. The morphology of the particles depends on polymerization conditions (monomer ratios and surfactant), particle properties, and so on. Then, the minimum surface free energy change principles were used to predict the equilibrium morphologies of the magnetic polymer composites. Through theory, the model gives the correct tendency and good agreement with the equilibrium morphology which was in tandem with TEM results. Lastly, after in situ surface deposition of Ag nanoparticles, magnetic composite particles with sandwich-like morphology were applied for the catalytic degradation of 4-nitrophenol (4-NP) reacting with NaBH4. The apparent rate coefficient is 0.0069 s-1, and it can keep mainly about 80% efficiency in catalysis after five cycles.

Enhancing formation and retention of hollow structural integrity through intermediate and outermost layer design in seeded emulsion polymerization of hollow latex particles

AbstractThe synthesis of hollow latex particles through seeded emulsion polymerization involves a series of intricate steps, including the formation of distinct polymer layers with specific properties. Despite extensive research, preserving the desired hollow structure remains challenging due to the unclear role of the encapsulating polymer layers. This study systematically adjusts the glass transition temperature (Tg) of the intermediate layer by varying the butyl acrylate (BA) ratio in the monomer feed mixture. By controlling the reaction temperature during alkali swelling, we explore the critical influence of Tg on hollow latex particle formation from carboxylated core latex particles. To ensure long‐term hollow structure retention after drying, a rigid outer layer is polymerized onto the intermediate layer. Surprisingly, higher divinylbenzene (DVB) mass ratios (5.0 and 10.0 wt%) do not result in a highly crosslinked hollow shell due to DVB self‐nucleation. This paper emphasizes the importance of precise design parameters for both intermediate and outermost layers in achieving and maintaining hollow latex particle structures. Understanding each layer's role and optimizing their compositions contribute to advancing hollow latex particle synthesis through seeded emulsion polymerization.

Maintenance-free antifouling polymeric membrane potentiometric sensors based on self-polishing coatings.

Polymeric membrane ion-selective electrodes (ISEs) have been widely used in environmental monitoring. However, in complicated marine environments, marine biofouling usually becomes a sticky problem for these electrodes. Herein, for the first time, a novel maintenance-free antifouling potentiometric marine sensor based on a self-polishing coating (SPC) is proposed. The SPC is synthesized by using the seeded emulsion polymerization method based on the triisopropylsilyl methacrylate monomer as the regulator of the self-renewal rate. This coating can be simply modified onto the electrode surface by drop-casting. The silyl acrylate side groups of the obtained SPC on the sensor surface can be hydrolyzed in the marine alkaline medium. The shear movement of seawater driven by sea waves, wind, gravity, or vibration removes the leftover (fouled) brittle polymer backbone and thus the fouling marine microorganisms. As a proof-of-concept experiment, a polymeric membrane Ca2+-ISE is chosen as a model. Compared to the unmodified electrode, the SPC-coated Ca2+-ISE exhibits remarkable improved antifouling properties in terms of superior anti-adhesive abilities towards marine microorganisms, such as bacterial cells and algae and excellent long-term stability even in the presence of high levels of marine microorganisms. Since no additional manual maintenance is required for maintaining the antifouling abilities of the sensor, the proposed self-polishing sensor may lay an important foundation for construction of unattended long-term potentiometric monitoring systems in real marine environments.

CaCO3-TiO2 IMPREGNATED AlOE VERA-ALLYL METHACRYLATE ANTIMICROBIAL NANOEMULSION FOR COATING

The present work aims to utilize AMA/MMA/BA/Aloe Vera (AMBA) nanoemulsion for the preparation of sustainable antimicrobial coating materials. The AMBA was synthesized using a semi-continuous seeded emulsion polymerization methodology. The developed coating material has been synthesized by SEM, DSC, TGA/DTA, XRD, and FT-IR spectroscopy. Some properties such as viscosity, hot box stability gloss retention, solid content, freezethaw stability, scrub resistance, electrolytic stability, weather resistance, solvent resistance, and opacity of the coating material were also investigated. It has been found that the coating developed with a 70:30 monomer ratio shows the best results the with highest antimicrobial activity.

Revealing the Formation Dynamics of Janus Polymer Particles: Insights from Experiments and Molecular Dynamics.

Seeded emulsion polymerization is one of the best-known methods for preparing polymer particles with a controlled size, composition, and shape. It first requires the preparation of seed particles, which are then swollen with additional monomer (the same as the one used for the seed or a different one), to either increase the seed's size or change its morphology. The use of surfactants plays a central role in guaranteeing the required colloidal stability and contributing to the final shape and structure of the particles by lowering the interfacial energy between the polymer of the seed and the added monomer. We here study the polymerization of methyl methacrylate in the presence of polystyrene seed particles at various surfactant concentrations in the presence and absence of a surfactant (sodium dodecyl sulfate). We first show experimentally that the morphology of the colloidal particles can be tuned from Janus to core-shell, depending on the presence or absence of surfactant on the seeds particles' surface. Furthermore, using classical molecular dynamics simulations, we investigate the mechanism and behavior of the surfactants during the first stages of the polymerization process. We use a newly developed approach based on contact statistical analysis to confirm the critical role played by the organization of surfactant molecules on the surface of the seed particles in dictating the final particle morphology.

Thermomechanical study on toughened PVC with an impact modifier based on the acrylonitrile-styrene-acrylate core-shell particles

Development of impact modifiers with the core-shell structure for enhancing toughness of rigid polymers have attracted a great deal of interest. In this study, poly (butyl acrylate) (PBA) as the core was prepared via emulsion polymerization and subsequently grafted with styrene and acrylonitrile (SAN) to construct the shell layer through seeded emulsion polymerization and to produce ASA particles. Then, ASA particles containing 40, 50, and 60 wt% of PBA core and those with non-crosslinked shell were compounded with PVC through melt-blending technique in different compositions. DLS, SEM and TEM analyses revealed uniform spherical core-shell morphologies with average particle size of 170–190 nm. Cross-sectional SEM images exhibited a well-distribution and dispersion of ASA particles in PVC matrix relative to the non-crosslinked one. This can be attributed to the formation and grafting of the rigid thermoplastic SAN layer on the PBA core. Impact results of the prepared compounds showed an increasing trend with the increase in core content and also amount of ASA. The highest impact strength (135 kJ/m2) was found for the compound containing 15 wt% of ASA (with 60 wt% of PBA core) particles, which was 26 times higher than the neat PVC (5 kJ/m2). A comparative study between PVC compounds demonstrated higher heat deformation temperature, elastic modulus, and impact strength for those containing ASA with the crosslinked shell. Remarkable compatibility with PVC matrix and enhancement in thermomechanical properties for the prepared core-shell ASA particles revealed their promising potential for toughening of PVC.

Surface Nucleation-Induced Raspberry-like PVDF@P(St-co-MPS-co-AA) Core–Shell Latex Particles via Seeded Emulsion Polymerization and Their High Efficiency for Confined Crystallization of PVDF in Nanospheres

Surface Nucleation-Induced Raspberry-like PVDF@P(St-<i>co</i>-MPS-<i>co</i>-AA) Core–Shell Latex Particles via Seeded Emulsion Polymerization and Their High Efficiency for Confined Crystallization of PVDF in Nanospheres

Durability improvement mechanism of polymer cement protective coating based on functionalized MXene nanosheets modified polyacrylate emulsion

Polymer cement coatings (PCCs) have a wide range of applications in the field of concrete protection. Excellent durability of the PCCs is extremely essential for protecting the concrete in long-time service life. However, one of the most popular polymer emulsion, polyacrylate based cement coatings show insufficient durability and restrict their wide application in complicated and harsh environment. In this study, the novel two-dimensional nanomaterial MXene was incorporated to PCCs for improving the durability of the PCCs, the MXene was functinalized by vinyl triethylsilane (VTEO) (V-MXene) followed by in-situ seed emulsion polymerization method to synthesize the V-MXene modified polyacrylate emulsion. The effects of V-MXene incorporation on the rheological property, mechanical properties, bonding strength, UV aging resistance, saltwater immersion resistance, thermal aging resistance of PCCs were systematically investigated and the durability improvement mechanism was revealed. When the V-MXene dosage is 0.15 wt%, the tensile strength and bonding strength of the PCCs increased by 28.76 % and 30.84 % as compared with the blank samples, respectively. The introduction of V-MXene to PCCs can remarkably improve the UV aging resistance, saltwater immersion resistance, heat resistance. The V-MXene can decrease the UV radiation energy absorbed into the PCCs, and can create a “labyrinth effect”, prolonging the penetration path of water and corrosion ions. The V-MXene can also enhance the cross-linking density of the polymer phase combined with organic and inorganic interpenetrating networks, thereby enhancing the thermal stability of PCCs. This research provides a feasible strategy for the fabrication of high performance PCCs with excellent durability.

Mechanical Properties and Non-Isothermal Crystallization Kinetics of Polylactic Acid Modified by Polyacrylic Elastomers and Cellulose Nanocrystals.

In this paper, a polyacrylic elastomer latex with butyl acrylate (BA) as the core and methyl methacrylate (MMA) copolymerized with glycidyl methacrylate (GMA) as the shell, named poly(BA-MMA-GMA) (PBMG), was synthesized by seeded emulsion polymerization. Cellulose nanocrystal (CNC) was dispersed in the polyacrylic latex to prepare PBMG/CNC dispersions with different CNC contents. The dried product was mixed with polylactic acid (PLA) to fabricate PLA/PBMG/CNC blends. The addition of PBMG and PBMG/CNC improved the mechanical properties of the PLA matrix. Differential scanning calorimetry (DSC) was used to investigate the non-isothermal crystallization kinetics. The Avrami equation modified by the Jeziorny, Ozawa and Mo equations was used to analyze the non-isothermal crystallization kinetics of PLA and its blends. Analysis of the crystallization halftime of non-isothermal conditions indicated that the overall rate of crystallization increased significantly at 1 wt% content of CNC. This seemed to result from the increase of nucleation density and the acceleration of segment movement in the presence of the CNC component. This phenomenon was verified by polarizing microscope observation.

Fabrication of Novel Crosslinking Carboxylic Styrene-Acrylate Latices as Binders for Exterior Flexible Facing Tiles.

To overcome the shortcomings of the temperature sensitivity of exterior flexible facing tiles (EFFIs), a series of crosslinking carboxylic styrene-acrylate (SA) latices were prepared via the semicontinuous seed emulsion polymerization of glycidyl methacrylate (GMA), methacrylic acid (MAA), acrylic acid (AA), butyl acrylate (BA), and styrene (St), and were applied as binders to fabricate EFFTs with mineral powder. The obtained latices exhibited Bragg diffraction because of the narrow particle size distribution. Owing to the low dosage of emulsifiers and the crosslinking reaction between the epoxy group and the carboxyl group, the latex films displayed excellent water resistance, with water adsorption as low as 7.1%. The tensile test, differential scanning calorimeter (DSC) test, and dynamic mechanical analysis (DMA) indicated that at a GMA dosage of 4-6% the latex films had high mechanical strengths, which remained relatively stable in the temperature range of 10 to 40 °C. The optimal AA dosage was found in the range of 2 to 3%, at which the wet mixture exhibited good processability, conducive to forming an EFFT with a compact microstructure. Using the optimal SA latex, the obtained EFFT displayed a series of improved performances, including low water absorption, high mechanical strength, and stable self-supporting ability over a wide temperature range, exhibiting the application potential in the decoration and construction industries.

Preparation and Characterization of Self-crosslinked Acrylate Emulsified with Environmentally Friendly Surfactants

The self-crosslinking polyacrylate latex was prepared via the semi-continuous seed emulsion polymerization technology that methyl methacrylate(MMA) and butyl acrylate (BA)were used as the main monomers and hexafluorobutyl methacrylate (HFMA) and monobutylitaconate (MBI) were used as the modified monomers and glycidyl methacrylate (GMA) was used as the crosslinked monomer which were emulsified with the environmentally friendly mixed surfactant of the isomeric triethylene (9) ether (E-1309) and the lauryl polyoxyethylene ether sulfosuccinate disodium salt (MES-30). The resultant latex and its film is characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), laser particle sizer, contact angle determinator. The comparison of thermal stability between the resultant latex and conventional latex is carried out via the thermogravimetric analyzer (TGA). Factors, which have an influence on the properties of the resultant latex and the emulsion polymerization, are studied in detail. Results indicate that the thermal decomposition temperature of the latex film was increased from 336.9 °C to 370.1 °C The contact angle of the latex film is 82.9 ° owing to the introduction of GMA and MBI.

Engineering the surface patchiness and topography of polystyrene colloids: From spheres to ellipsoids

HypothesisColloidal surface morphology determines suspension properties and applications. While existing methods are effective at generating specific features on spherical particles, an approach extending this to non-spherical particles is currently missing. Synthesizing un-crosslinked polymer microspheres with controlled chemical patchiness would allow subsequent thermomechanical stretching to translate surface topographical features to ellipsoidal particles. ExperimentsA systematic study using seeded emulsion polymerization to create polystyrene (PS) microspheres with controlled surface patches of poly(tert-butyl acrylate) (PtBA) was performed with different polymerization parameters such as concentration of tBA monomer, co-swelling agent, and initiator. Thermomechanical stretching converted seed spheres to microellipsoids. Acid catalyzed hydrolysis (ACH) was performed to remove the patch domains. Roughness was characterized before and after ACH using atomic force microscopy. FindingsPS spheres with controlled chemical patchiness were synthesized. A balance between two factors, domain coalescence from reduced viscosity and domain growth via monomer absorption, dictates the final PtBA) patch features. ACH mediated removal of patch domains produced either golf ball-like porous particles or multicavity particles, depending on the size of the precursor patches. Patchy microspheres were successfully stretched into microellipsoids while retaining their surface characteristics. Particle roughness is governed by the patch geometry and increases after ACH. Overall, this study provides a facile yet controllable platform for creating colloids with highly adjustable surface patterns.

Synthesis of Composite Polymer Particles by Seeded Emulsion Polymerization and Formation of Photonic Crystals Based on Them

Synthesis of Composite Polymer Particles by Seeded Emulsion Polymerization and Formation of Photonic Crystals Based on Them

Synthesis of Composite Polymer Particles by Seeded Emulsion Polymerization and Formation of Photonic Crystals Based on Them

Submicron composite particles with the core/shell structure are synthesized by the seeded emulsion polymerization of a mixture of various acrylates in the presence of a redox initiation system. The diameter, morphology, and surface structure of particles as well as their ability to self-assemble into 3D ordered thin-film structures are studied by scanning electron microscopy, FTIR spectroscopy, thermogravimetry, and dynamic light scattering. It is shown that under the used experimental conditions particles with a shell thickness of 10‒35 nm are synthesized. The effect of shell composition (in particular, the alkyl chain length of acrylate comonomers) on the morphology and structure of the surface layer of the obtained composite particles is traced.