Polyisoprene-silica (PIP-co-RAFT-SiO2) nanoparticles were prepared via reversible addition–fragmentation chain-transfer (RAFT) emulsifier-free emulsion polymerization using water-soluble initiators, 4,4′-Azobis (4-cyanopentanoic acid) (ACP) and 2,2′-Azobis (2-methylpropionamidine) dihydrochloride (V50). The particle size of emulsion prepared using ACP initiator was smaller than that using V50 initiator because the V50 initiator was more active toward decomposition than the ACP initiator. A high monomer conversion (84%), grafting efficiency (83%) and small particle … Continue reading Polyisoprene-Silica Nanoparticles Synthesized via RAFT Emulsifier-Free Emulsion Polymerization Using Water-Soluble Initiators

A major drawback of conventional emulsion polymers arises from the presence of migrating low molar mass surfactants that contribute to poor water barrier properties and low adhesion to substrates. In this paper, we demonstrate how living polymer chains obtained by reversible addition–fragmentation chain transfer (RAFT) can be used as an efficient stabilizer in emulsion polymerization, leading to the production of surfactant-free latexes, which then form … Continue reading Hydrophilic MacroRAFT-Mediated Emulsion Polymerization: Synthesis of Latexes for Cross-Linked and Surfactant-Free Films

Although surfactants are known to play a vital role in polymerization reactions carried out in dispersed media, many aspects of their use are poorly understood, perhaps none more so than the vastly different action of ionic and nonionic surfactants in emulsion polymerization. In this work, we combine experimental measurements of emulsion polymerization of styrene with atomistic molecular dynamics simulations to better understand the behavior of … Continue reading Shedding Light on the Different Behavior of Ionic and Nonionic Surfactants in Emulsion Polymerization: From Atomistic Simulations to Experimental Observations

This paper presents a facile and efficient synthesis method to fabricate epoxy-acrylate copolymer/nano-silica latex via Pickering emulsion polymerization stabilized by silica sol. The effects of solid contents, silica concentration and polymerization time on emulsion polymerization were studied. The core-shell epoxy-acrylate copolymer/nano-silica was obtained with average diameter 690 nm, was observed by Transmission Electron Microscopy (TEM) and Dynamic Light Scattering (DLS). The formation mechanism of epoxy-acrylate … Continue reading Preparation of epoxy-acrylate copolymer/nano-silica via Pickering emulsion polymerization and its application as printing binder

We report an easy route to surfactant-free micro- and nanolatexes of polystyrene dispersed in water from Pickering emulsion systems, using modified cellulose nanocrystals as stabilizing particles. Each step of the formation of these latexes was thoroughly investigated: modification of the cellulose nanocrystals, colloidal properties of the emulsions, impact of the polymerization initiator, impact of the ionic strength and mechanisms leading to the formation of the … Continue reading Synthesis of surfactant-free micro- and nanolatexes from Pickering emulsions stabilized by acetylated cellulose nanocrystals

A series of ultraviolet (UV)-curable self-healing polyurethane (PU) oligomers were synthesized by incorporating different contents of 2-ureido-4[1H]-pyrimidone and polycarbonate diols (PCDL) with different molecular weights at the end of PU chains. The structure of the oligomers were determined through Nuclear magnetic resonance (1H NMR) and Fourier transform infrared spectroscopy. The PU oligomers were used to produce UV-curable self-healing coatings, the properties of which were investigated … Continue reading The features of emulsion copolymerization for plant oil-based vinyl monomers and styrene

Aqueous emulsion polymerization is by far the most important method for synthesizing polymer nanoparticles. In this work we report a new type of surfactant-free emulsion polymerization process for one-step formation of monodisperse poly(methyl methacrylate)@SiO2 core-shell nanoparticles. The strategy utilizes a silica precursor polymer, hyperbranched polyethoxysiloxane (PEOS), whose chemical structure can be adapted by hydrolysis at water/oil interfaces for their stabilization. The core-shell particles are obtained … Continue reading One-Pot Formation of Monodisperse Polymer@SiO2 Core-Shell Nanoparticles via Surfactant-Free Emulsion Polymerization Using an Adaptive Silica Precursor Polymer

To improve the corrosion resistance of waterborne polyacrylate latexes coatings, an epoxy/polyacrylate (EP/PA) composite latex with high EP content was developed viaminiemulsion polymerization as the matrix of anticorrosion coatings. Transmission electron microscopy illustrated that the EP/PA composite had spherical shapes with the diameter of 130–199 nm. In addition, differential scanning calorimeter and thermal gravity analysis thermograms suggested that the EP/PA composites showed good compatibility and thermal stability. … Continue reading Synthesis of waterborne epoxy/polyacrylate composites via miniemulsion polymerization and corrosion resistance of coatings

Waterborne few-layer graphene oxide/poly(methyl methacrylate-co-butyl acrylate), FLGO/poly(MMA-co-BuA), nanocomposites were synthesized by in situ emulsion polymerization. The FLGO nanosheets used in this study was prepared by modified Hummers method and followed by an exfoliation process. The obtained FLGO and both latex and film forms of the nanocomposites were characterized in detail. It was found that the interactions between FLGO and copolymer matrix, and therefore the nanocomposite properties including … Continue reading Synthesis and properties of waterborne few-layer graphene oxide/poly(MMA-co-BuA) nanocomposites by in situ emulsion polymerization

The environmentally-friendly synthesis of epoxy-functional spherical nanoparticles has been achieved using polymerization-induced self-assembly (PISA) in aqueous solution. Firstly, a non-ionic hydrophilic stabilizer block, poly(glycerol monomethacrylate) (PGMA), was prepared by reversible addition–fragmentation chain transfer (RAFT) solution polymerization in ethanol. This water-soluble precursor was subsequently chain-extended via RAFT aqueous emulsion polymerization of glycidyl methacrylate (GlyMA) at 50 °C and neutral pH to ensure maximum retention of the epoxy functionality. … Continue reading Synthesis of well-defined epoxy-functional spherical nanoparticles by RAFT aqueous emulsion polymerization

In the present contribution, the optimization of coating properties of structured self-crosslinking latexes based on diacetone acrylamide and adipic acid dihydrazide crosslinking system by varying particle design and molar mass was investigated. Latexes were prepared by the semi-continuous non-seeded emulsion polymerization of methyl methacrylate, butyl acrylate, diacetone acrylamide and methacrylic acid as main monomers. Two series of latex particles of hard-core/soft-shell or soft-core/hard-shell design were … Continue reading Property study of structured self-crosslinking acrylic latex binder: Effect of molar mass and particle design

A feasible approach to synthesis self-healing materials via environment-friendly emulsion polymerization is described, which possess high mechanical strength for application as polymer coatings. UPy-functionalized monomer is synthesized via a simple one-step reaction procedure, which is incorporated into the polymeric matrix to establish a supramolecular crosslinking network. UPy groups endow the latex films a high self-healing property on a thorough fracture. And recovery rate of tensile … Continue reading Emulsion polymerization to synthesize self-healing films toward healing on fractures: A feasible strategy

In this study, poly (n-butyl acrylate-co-2-ethyl hexyl acrylate) (P(nBA-co-2EHA)) pressure sensitive adhesives (PSAs) were successfully synthesized in the presence of cellulose nanocrystals (CNCs) via in-situ miniemulsion polymerization. First, the CNCs were prepared via acid hydrolysis of cellulose microcrystals (CMCs) at various temperatures, 42–54 °C, and characterized using atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) apparatus. The … Continue reading Cellulose nanocrystals (CNCs) reinforced acrylic pressure- sensitive adhesives (PSAs) prepared via miniemulsion polymerization

Sodium styrene sulfonate (NaSS) was used to stabilize waterborne poly(methyl methacrylate/butyl acrylate) dispersions obtained by surfactant-free seeded semicontinuous emulsion polymerization at 50 wt% solids content. The effect of NaSS concentration (0.175–3.6 wbm%) on the reaction kinetics, NaSS incorporation onto particles, colloidal stability and properties of emulsifier-free latexes and films was investigated. It was found that fraction of NaSS that was incorporated onto polymer particles increased with its … Continue reading Effect of ionic monomer concentration on latex and film properties for surfactant-free high solids content polymer dispersions

Methodology for the successful implementation of RAFT (4-cyano-4[(dodecylsulfanylthiocarbonyl)sulfanyl]pentanoic acid (CDTPA)) iniferter polymerization of butyl methacrylate in miniemulsion using visible light (green light; λmax = 530 nm) has been developed. Under suitable conditions, the polymerization proceeds to high conversion with good control/livingness, generating polymeric nanoparticles in the approximate diameter range of 100–200 nm. The surfactant loading is a crucial parameter – if the concentration of free … Continue reading RAFT Iniferter Polymerization in Miniemulsion Using Visible Light

A series of core–shell pressure-sensitive adhesives (PSAs) containing a poly(n-butyl-co-2-ethylhexyl acrylate) shell copolymer were synthesized via a multi-step emulsion process. The weight ratio of n-butyl acrylate (BA) to 2-ethylhexyl acrylate (2-EHA) was manipulated to vary the PSA properties. Measuring performance parameters of the resulting PSAs showed that increasing the relative amount of BA led to a decrease in the tack strength but an increase in … Continue reading Effect of The n-butyl acrylate/2-ethylhexyl acrylate Weight Ratio on The Performances of Waterborne Core–Shell PSAs

The use of sulfur free reversible addition–fragmentation chain transfer polymerisation (RAFT) as a versatile tool for the controlled synthesis of methacrylic block and comb-like copolymers was demonstrated. Sulfur free RAFT (SF-RAFT) utilises vinyl terminated macromonomers obtained via catalytic chain transfer polymerisation (CCTP) of methacrylates as a chain transfer agent (CTA), and thus precluding adverse aspects of the RAFT such as toxicity of dithioesters. We have … Continue reading Methacrylic Block Copolymers by Sulfur Free RAFT (SF RAFT) Free Radical Emulsion Polymerisation

Latex nanoparticles comprising cationically charged coronas and hydrophobic cores with different glass transition temperatures (Tg) have been prepared by surfactant-free, RAFT-mediated emulsion polymerization, where the particles form through a polymerization-induced self-assembly (PISA) type mechanism. Poly(2-dimethylaminoethyl methacrylate-co-methacrylic acid) (P(DMAEMA-co-MAA)) was utilized as a hydrophilic macroRAFT agent for the polymerization of methyl methacrylate (MMA) or n-butyl methacrylate (nBMA), respectively, resulting in two different latexes, with either a … Continue reading Soft and Rigid Core Latex Nanoparticles Prepared by RAFT-mediated Surfactant-Free Emulsion Polymerization for Cellulose Modification

This work demonstrates the fabrication of terpene based sustainable methacrylate polymers by an environmentally benign emulsion polymerization method. The polymerization reaction has been found to be influenced by the side chain length of the methacrylate(s), which has been quantitatively calculated from the density functional theory. Apart from the analysis of the copolymer microstructure, various properties of the synthesized polymers have been studied and correlated with … Continue reading Terpene based Sustainable Methacrylate Copolymer Series by Emulsion Polymerization

Non-spherical (ns) hollow latex (HL) particle with a void on one side of a polymer particle surrounded by a double-layered shell was fabricated via the one-pot seeded emulsion polymerization (SEP). Start from the ns seed formed by swelling styrene (St) or methyl methacrylate (MMA) mixed with azobisisobutyronitrile into a crosslinked spherical poly(styrene/divinyl benzene/acrylic acid) P(St/DVB/AA) particle and then polymerized. The ns seed particle having two … Continue reading One-pot Synthesis of Non-spherical Hollow Latex Polymeric Particles via Seeded Emulsion Polymerization

Concern for the environment has been driving major changes in the coatings industry. To reduce the amount of volatile organic compounds (VOC’s) released to the atmosphere; new technology and deeper understanding should be developed to replace solvent-based coatings with water-based coatings. Most of these coatings contain latex particles prepared by emulsion polymerization, referred to as primary dispersions. Secondary dispersions are polymer nanoparticles in water normally … Continue reading Understanding Particle Formation in Surfactant-free Waterborne Coatings Prepared by Emulsification of Pre-formed Polymers