Emulsion Copolymerization Of Styrene Research Articles

Latex particles by emulsion and dispersion polymerizations: sensitization with specific antigens of leptospirosis and application to immunoagglutination

The controlled synthesis of polymer nanoparticles is of great interest in the production of latexes with well defined characteristics. These products can be applied in biomedicine as carriers of biomolecules (e.g. proteins and enzymes), and in particular as latexes for immunoassays used for example in immunoagglutination test, which allow amplify the antigen–antibody reaction, being simple, quick and inexpensive diagnostic tools. The synthesis of polystyrene (PS) latex particles and of core–shell particles, with controlled size distribution, functional groups and surface charge densities is considered here. PS latexes were synthesized in the 100–1100 nm diameter range, by either emulsion or dispersion polymerization. Such latexes were then used as seeds in emulsion copolymerizations of styrene and a functional monomer (methacrylic acid or glycidyl methacrylate), thus producing particles with carboxyl or epoxy functionalities, respectively. Changes in the polymerization recipes employed under batch operation were analyzed. Latex characterization involved measurements of mean particle diameters, the polydispersity index, functional group densities and zeta potential. Finally, latexes were sensitized (by either physical adsorption or covalent coupling) with specific antigens to obtain latex–protein complexes, and one of them was tested as agglutination assay for detecting leptospirosis disease in bovine samples, as an example of the potential application of the latexes produced.

Free‐radical emulsion copolymerization of styrene with butadiene and vinyl triethoxysilane with a cumene hydroperoxide redox initiator

ABSTRACTThe emulsion free‐radical copolymerization of vinyl triethoxysilane (VTES) with styrene (St) and butadiene (Bd) was initiated by cumene hydroperoxide and ferrous sulfate at 0 °C. The effects of VTES on the copolymerization conversion, reaction time, gel content, latex particle size, thermal stability, and mechanical properties were thoroughly investigated. The success of this reaction was confirmed by the peaks attributed to both Si─O─Si groups at 1065 cm−1 and the Si─O─C bond at 1046 cm−1. A kinetics analysis showed that the conversion decreased with increasing VTES mass in the monomer feed. Compared with that in the St–Bd copolymer, the latex particle size increased slightly with increasing VTES mass. The Mooney viscosity and gel content results show that a large fraction of precrosslinking molecular chains was formed in the rubber particles. The thermogravimetric analysis results indicate that the thermal stability of the copolymers increased with increasing VTES concentration. The 300% modulus and tensile strength of the St–Bd–VTES copolymer increased with the mass of VTES at first and then decreased after 3 phr VTES, whereas the elongation at break decreased with increasing VTES mass. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47896.

Emulsion Copolymerization of Styrene With n‐Butyl Acrylate and Methacrylic Acid: Effect of Kraft Lignin Concentration and Peroxide Treatment on the Colloidal Properties

The focus of this work is to understand the effect of Kraft lignin (KL) treatment with tert‐butyl hydroperoxide (TBHP) and sodium formaldehyde sulfoxylate (SFS) on the properties of the latexes produced by emulsion copolymerization of styrene (Sty) with n‐butyl acrylate (BuA) and methacrylic acid (MAA), with initiator introduced in a shot process. The study intends to understand the effect of KL concentration after peroxide treatment on the properties not only of the latexes, but also on the copolymers themselves. Latexes were characterized in relation to global conversion, average particle size, zeta potential, coagulum concentration, surface tension and latex stability. The polymers were evaluated through molar mass and molar mass distributions, thermogravimetric analysis, and differential scanning calorimetry. The solubility of the KL in water and water/glycol were presented as a function of pH and KL concentration. Stable latexes were produced via emulsion copolymerization with different amounts of KL. The redox initiator system employed in the KL treatment was not efficient to obtain higher conversions. The increase of the KL concentration caused reduction of overall conversion, particle diameter, stability, molar mass and zeta potential. Among the concentrations tested, the greatest concentration of KL, 6.8 wt% relative to the mass of monomer, exhibited the greatest effect on the properties of the latexes and polymers.

Surfactant‐free emulsion copolymerization of styrene and methyl methacrylate for preparation of water‐redispersible polymeric powders

ABSTRACTPoly(methyl methacrylate), polystyrene, and poly(styrene‐co‐methyl methacrylate) cationically stabilized latexes with up to 25% solid content were prepared by surfactant‐free emulsion polymerization (SFEP) employing 1 mol % 2,2′‐azobis[2‐(2‐imidazolin‐2‐yl)propane]dihydrochloride (VA‐044) as an initiator and stabilizer (inisurf) with respect to monomer at 70 °C. The latexes had 200–500 nm z‐diameter and a very narrow size distribution (PDI < 0.05). The stabilizing amidinium moieties from VA‐044 were covalently bound to the particles. After drying in air, poly(styrene‐co‐methyl methacrylate), PS‐co‐PMMA latexes were easily redispersible in water simply by addition of water and a few minutes of gentle stirring. The redispersed latex particles had colloidal characteristics very similar to the original latex particles in terms of polydispersity, size, and zeta potential. In contrast, latexes prepared with a similar formulation but using a conventional cationic surfactant (CTAB) that was not covalently bound to the particles were not redispersible. This is the simplest method reported so far for the preparation of redispersible latexes that do not use high stabilizer concentrations. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2376–2381

Adsorption and covalent binding of fibrinogen as a method for probing the chemical composition of poly(styrene/α-tert-butoxy-ω-vinylbenzyl-polyglycidol) microsphere surfaces

We investigated the distribution of polyglycidol and polystyrene on the surface of poly(styrene/α-tert-butoxy-ω-vinylbenzyl-polyglycidol) microspheres (random distribution or segregated into hydrophilic and hydrophobic patches), using fibrinogen (Fb) as a macromolecular probe. The fibrinogen was adsorbed or covalently attached to the surface of the poly(styrene-co-α-tert-butoxy-ω-vinylbenzyl-polyglycidol) (P(S/PGLy)) microspheres. The P(S/PGLy) particles were prepared by emulsion copolymerization of styrene and α-tert-butoxy-ω-vinylbenzyl-polyglycidol (PGLy) macromonomer initiated with potassium persulfate. The polymerizations yielded P(S/PGLy) particles with various surface fractions of polyglycidol, depending on the amount of added macromonomer and the addition process. In some syntheses, the entire macromonomer amount was added once at the beginning of the polymerization, while in others, the macromonomer was added gradually after the formation of particle seeds from pure polystyrene. XPS studies revealed that the fraction of polyglycidol in the interfacial layer of the microspheres was larger when the entire amount of macromonomer was added at the beginning of the polymerization than when it was added after formation of the polystyrene seeds. Studies of fibrinogen adsorption provided the first evidence of segregation of the hydrophobic (polystyrene) and hydrophilic (polyglycidol) components at the surface of the composite P(S/PGLy) microspheres into patches. The hydrophobic patches are composed mainly of polystyrene. However, they also contain a small amount of polyglycidol chains, making the adsorption of fibrinogen weaker than the adsorption onto the pure polystyrene. Studies of covalent immobilization of fibrinogen on the microspheres via 1,3,5-trichlorotriazine confirmed these findings.

Tertiary amine‐containing poly(methyl methacrylate–butadiene–styrene) core/shell nanoparticles with CO 2 ‐triggered aggregation behaviour

A new kind of poly(methyl methacrylate–butadiene–styrene) (MBS) core/shell latex nanoparticles with amine groups in the shell was prepared via multistep seeded emulsion copolymerisation of styrene, methyl methacrylate and N,N-diethylaminoethyl methacrylate (DEAEMA) onto the poly(styrene–butadiene) seed latex in the presence of anionic emulsifier, and their CO2-triggered coagulating properties were investigated. Results showed that the emulsion polymerisation could be performed smoothly, and the coagulating time of the amine-containing MBS latexes depended on the DEAEMA content and solid content. The MBS solid powder could be easily obtained by drying and grinding without any extra treatment after the coagulation. A coagulating mechanism of the in-situ opposite charge interaction and the transformation from sodium laurate to lauric acid was proposed, which was demonstrated by transmission electron microscopy, dynamic light scattering, surface tension and Zeta potential measurements. This facile and smart method might open up industrial potential in cost-effective and environment-friendly latex coagulation.

A series of nanoparticles with phase-separated structures by 1,1-diphenylethene controlled one-step soap-free emulsion copolymerization and their application in drug release

A facile one-step approach to synthesize various phase-separated porous, raspberry-like, flower-like, core–shell and anomalous nanoparticles and nanocapsules via 1,1-diphenylethene (DPE) controlled soap-free emulsion copolymerization of styrene (S) with glycidyl methacrylate (GMA), or acrylic acid (AA) is reported. By regulating the mass ratio of S/GMA, transparent polymer solution, porous and anomalous P(S-GMA) particles could be produced. The P(S-GMA) particles turn from flower-like to raspberry-like and then to anomalous structures with smooth surface as the increase of divinylbenzene (DVB) crosslinker. Transparent polymer solution, nanocapsules and core–shell P(S-AA) particles could be obtained by altering the mole ratio of S/AA; anomalous and raspberry-like P(S-AA) particles are produced by adding DVB. The unpolymerized S resulted from the low monomer conversion in the presence of DPE aggregates to form nano-sized droplets, and migrates towards the external surfaces of the GMA-enriched P(S-GMA) particles and the internal bulk of the AA-enriched P(S-AA) particles. The nano-sized droplets function as in situ porogen, porous P(S-GMA) particles and P(S-AA) nanocapsules are produced when the porogen is removed. This novel, facile, one-step method with excellent controllability and reproducibility will inspire new strategies for creating hierarchical phase-separated polymeric particles with various structures by simply altering the species and ratio of comonomers. The drug loading and release experiments on the porous particles and nanocapsules demonstrate that the release of doxorubicin hydrochloride is very slow in weakly basic environment and quick in weakly acidic environment, which enables the porous particles and nanocapsules with promising potential in drug delivery applications.

Cationic styrene-butyl acrylate-quaternary ammonium copolymer nanospheres for surface modification of cotton fibers

Cationic copolymer nanospheres are important functional materials, for example, for fiber modification. Here, emulsifier-free ternary emulsion copolymerizations of styrene (St) and butyl acrylate (BA) with two different quaternary ammonium cationic monomers (QACMs), methacryloxyethyl trimethyl ammonium chloride (DMC) and trimethyl (vinylbenzyl) ammonium chloride (VBT), and 2,2’-azobis[2-methylpropionamidine] dihydrochloride (AIBA) as an initiator were conducted at 80 ×C, under agitation at 300 rpm. The differences between the two cationic comonomers strongly influenced the monomer conversion, diameter, morphology, and surface charge density of the nanospheres. In particular, a higher cationic comonomer content is found to produce more oligomer radicals and thus more primary particles in the polymerization process, which leads to higher monomer conversion, smaller particle diameter, and increased surface charge density. The cationic nanospheres could be adsorbed in either a monolayer or in multiple layers on the oppositely charged cotton fiber because of their fierce electrostatic attraction. Compared with poly(St-BA-VBT) nanospheres, the distribution of poly(St-BA-DMC) nanospheres was more nonuniform on fiber surfaces accompanied by agglomerates.

The Synthesis and Properties of Emulsion Copolymerization of Styrene with N-Substituted Phenyl Maleimide

The synthesis and characterization of copolymer emulsions of styrene with two types of N-substituted phenyl maleimide (N-p-Methyl–MPhMI and N-m-Methyl–MPhMI) were investigated and researched in this thesis, by varying the mole fraction of N-substituted phenyl maleimide and using a seed emulsion polymerization process. The emulsion was steady with high yield, low intrinsic viscosity, and high solid content (40%). In this thesis, we studied that the substituted position on the benzene ring of the N - substituted phenyl maleimide has significant influence on emulsion properties and thermal properties of copolymer emulsion copolymer. The result shows that: the polarity of N-p-MPhMI is higher than N-m-MPhMI, which can significantly improve the yield, and reduces the emulsion gel rate. N-p-MPhMI is more electronegative than N-m-MPhMI, and N-p-MPhMI-St copolymer emulsion has high zero shear viscosity and low surface tension than N-m-MPhMI-St. And N-m-MPhMI-St copolymer emulsion decreased the viscosity of Pst homopolymer emulsion. However, N-p-MPhMI-St copolymer emulsion rheology curve changes into pseudoplastic fluid. The addition of the N-substituted phenyl maleimide can improve the heat resistance of polystyrene, and N-p-methylphenyl maleimide with styrene copolymer can increase the glass transition temperature of copolymer more remarkably than copolymer N- m-tolylmaleimide with styrene can do.

Interactions of serum proteins and alkaline phosphatase with poly(styrene/α‐tert‐butoxy‐ω‐vinylbenzyl‐polyglycidol) microspheres with various surface concentrations of polyglycidol

Interactions of human serum albumin, gamma globulins and alkaline phosphatase with surface of hydrophilic microspheres are described. Relation between the composition of particles surface layer and adsorption/covalent immobilization and activity of proteins is elucidated. The set of poly(styrene/α‐tert‐butoxy‐ω‐vinylbenzyl‐polyglycidol) microspheres (poly(S/PGly)) was synthesized via emulsion copolymerization of styrene and α‐tert‐butoxy‐ω‐vinylbenzyl‐polyglycidol (PGL) macromonomer (Mn = 3000, Mw/Mn = 1.08). The way of addition of PGL macromonomer was different in particular subsets of syntheses; however, the total concentration of all compounds added to the polymerization mixture was kept constant. Namely, PGL was continuously injected beginning injection at various stages of styrene conversion or it was added together with styrene at the beginning of the polymerization. The syntheses yielded microspheres with a number average diameter measured by SEM in a range from 300 to 564.7 nm, and dispersities (Dw/Dn) lower than 1.004, depending on the method of addition of PGL to the polymerization mixture. Studies of proteins' adsorption allowed for determination of relation between the surface concentration of adsorbed protein and chemical composition of the particles interfacial layer. Activation of hydroxyl groups in polyglycidol by 1,3,5‐trichlorotriazine allowed for the controlled covalent immobilization of proteins onto particles. The accompanying physical adsorption was low. Studies of the activity of alkaline phosphatase covalently bonded to the surface of the poly(S/PGly) particles with the fraction of PGL in the particles' interfacial layer (fPGL = 20.6 mol% revealed that the activity of the covalently immobilized enzyme was 4.6 times higher than activity of the enzyme adsorbed on the surface of the polystyrene microspheres. Copyright © 2014 John Wiley & Sons, Ltd.

A novel approach to prepare core/shell polymer latex particles with high sulphonate contents

Crosslinked x-P(St-MAA) seed latex was first prepared via soap-free emulsion copolymerization of styrene (St) and methyl methacrylic acid (MAA) with divinyl benzene as crosslinker and ammonium persulfate as initiator, and x-P(St-MAA)/x-P(St-NaSS) core/shell latex particles were then synthesized through a novel seeded emulsion copolymerization of St and sodium styrene sulphonate (NaSS) in the presence of water-soluble crosslinker N,N′-methylene bisacrylamide (BAA) using oil-soluble 2,2-azobis isobutyronitrile as initiator. TEM observation indicated that narrow dispersed core/shell latex particles were obtained, and element analysis showed that NaSS unit content in the whole particle and in the shell reached 22.8 wt% and 51.2 wt%, respectively.

Effect of water‐absorbing nanospheres on antistatic property of isotactic polypropylene fibers

ABSTRACTIn this article, novel antistatic isotactic polypropylene (iPP) fibers were prepared through adding ternary polymer water‐absorbing nanospheres (TPWANs) into iPP melt in melt spinning process. The TPWANs were synthesized through emulsion copolymerization of styrene (St), butyl acrylate (BA), and sodium allylsulfonate (SAS). The characterization results of Fourier transform infrared spectrometer (FT‐IR) and 1H nuclear magnetic resonance (1H NMR) confirmed the ternary components in this copolymer. Transmission electron microscopy (TEM) images indicated the nanospherical shape of TPWANs with the characteristics of 80–90 nm size range of diameter and good dispersion in iPP fibers. The volume resistance of iPP fibers decreased by three orders from 1012 to 109 Ω cm when the 6 wt % TPWANs was added into iPP fibers, indicating that the blend fibers have good antistatic property. Most importantly, the nanospherical structure of TPWANs imparts both the compatibility and antistatic property into the blend iPP fibers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40568.

Seeded Semibatch Emulsion Copolymerization of Styrene, Butadiene, and Carboxylic Acids in a Pilot Plant Reactor

The seeded semibatch emulsion terpolymerization of styrene–butadiene–acrylic acid is investigated in a pilot plant scale reactor of 151 L. The effect of the styrene–butadiene ratio (S/BD ratio), amount of tertiary-dodecyl mercaptan as chain transfer agent (CTA), and two temperature profiles on the kinetics of the process (solids content, styrene conversion, particle size, and acid partitioning), by-product formation (4-phenyl cyclohexane, 4-PCH, and 4-vinyl cyclohexane, 4-VCH) and the molar mass distribution of the sol and the fraction of gel are studied.

Emulsion copolymerization of styrene and acrylated methyl oleate

In this work, the emulsion copolymerization of styrene and acrylated methyl oleate (AMO), a monomer derived from oleic acid (OA), has been evaluated. Reactions exhibiting high monomers conversions were successfully performed, leading to the formation of very stable polymer lattices, whose average particle size is kept unchanged for relatively high storage times. The average molar masses determined by gel permeation chromatography showed to be very dependent on the amount of AMO in the reaction medium, presenting experimental values within the range from 280 000 to 39 000 g mol−1 with molar mass dispersity ranging from 4 to 2 when the AMO fraction in the reaction medium was increased to 40 wt%. The nucleation rate was affected by AMO in such way that an increase in AMO concentration must be accompanied by an increase in initiator concentration, which leads to the reduction of the average molar masses of the copolymer. The thermal analyses of the polymer materials showed that the glass transition temperature decreased with increasing amount of AMO in the copolymer chains.Practical applications: The use of vegetable oils and their derivatives as precursor monomers in polymerization reactions has increased each day due to their renewable origin. Among them, OA deserves special attention due to the high availability and ease of chemical modification, mainly when the double bounds are considered. Results showed that AMO could be incorporated at high ratios in emulsion polymerization reducing the glass transition temperatures of the copolymer. The polymer lattices also showed good storage stability.

Permanently antimicrobial waterborne coatings based on the dual role of modified poly(styrene-co-maleic anhydride)

Poly(styrene-alt-maleic anhydride) was successfully (partially) modified with N,N-dimethylaminopropylamine to yield the corresponding N-substituted maleimide with dangling tertiary amine functionality. The remaining maleic anhydride units were ammonolyzed to create a water-soluble polymer. This polymer was used as a polymeric surfactant in the emulsion copolymerization of styrene and n-butyl acrylate. The tertiary amine-functional polymer was further shown to possess antibacterial and antifungal properties. When post-added to a poly(styrene-co-butyl acrylate) latex, the antimicrobial activity was not homogeneously present on a coating film made from the latex. However, when the tertiary amine-functional polymer was used as surfactant in the preparation of the latex, the antimicrobial activity was homogeneous and consistent over the entire coating surface.

Preparation and properties of covalently colored polymer latex based on a new anthraquinone monomer

Abstract1‐(6‐acrylamidohexylamino)‐4‐(methylamino)anthraquinone (AHMAQ), a blue polymerizable dye, was first synthesized from an anthraquinone derivative, and its chemical structure was confirmed by 1H‐NMR and IR. Then, a series of covalently colored polymer latexes were prepared by semi‐continuous emulsion copolymerization of styrene (St), butyl acrylate (BA), and AHMAQ using 4,4′‐azobis(4‐cyanovaleric acid) (ACVA) as initiator, and the influences of AHMAQ and ACVA on the emulsion polymerization as well as the properties of the resulted copolymer latexes were investigated. Results showed that both the conversion of the dye monomer and the molecular weight of the latex polymer decreased with the increase of AHMAQ amount from 0 to 0.3 wt %. Increasing the ACVA amount resulted in higher monomer conversion but larger gel ratio, and optimum amount of ACVA was 1.2 wt % to the total monomers. Comparing with the noncovalently blue latex film colored with the unreactive dye, the light fastness of the blue P(St‐BA‐MAA‐AHMAQ) latex films was greatly promoted by the covalent incorporation of chromophores with polymer matrix. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Design and Synthesis of Novel Hematite Core-Shell Polymeric Composites

A novel synthetic method was developed for the preparation of core-shell composites consisting of α-Fe2O3cores with poly(styrene-co-methyl methacrylate) (P(St-co-MMA)) shells via emulsion copolymerization of styrene and methyl methacrylate monomer with surfactant of PVP. The structure, morphology and thermal properties of the composites were been characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). The results confirmed that there was no chemical interaction between α-Fe2O3and copolymer, and the onset of thermal decomposition for nanocomposites shifted to a higher temperature than that for neat copolymer.

Preparation of Covalently‐colored Polymer Latex via Batch Emulsion Polymerization

AbstractCovalently‐colored polymer latex was synthesized via batch emulsion copolymerization of styrene, butyl acrylate and methacrylic acid in the presence of red polymerizable dye monomer consisting of anthraquinone chromophore, alkyl spacer and acryloyl group, and the influences of the initiator, surfactant and polymerizable dye on the polymerization and the latex properties were investigated. Results showed that the initiator amount was a determinative factor for the monomer conversion, and a high conversion of the polymerizable dye could be achieved when the ammonium persulfate amount was equal to or more than 1 wt% to the total monomers. Most of the chromophores were covalently bonded to the polymer chains if the polymerizable dye was used in the range of 0–1.5 wt%. The light fastness of the resulting latex film was much better than that of the noncovalently‐colored polymer film.

Development of synthesis methods of sub-micron latex having desired surface properties for application in biotechnology

In this work were investigate features of the synthesis of monodisperse polymer particles by without emulgatoric cationic emulsion copolymerization of styrene and N-vinyl formamide. The characteristics of the synthesized particles (diameter, particle size distribution, ζ-potential of the particles, the concentration of surface functional groups). The results of modified phosphor particles, as well as sorption bioligands protein nature (bovine serum albumin).

Emulsion copolymerization of styrene and butyl acrylate by reverse atom transfer radical polymerization

AbstractReverse atom transfer radical copolymerization of styrene (St) and butyl acrylate was carried out in emulsion under normal emulsion conditions, using CuBr2/bpy complex as catalyst. The effects of surfactant type, initiator type and concentration, and CuBr2 addition on the system livingness, polymer molecular weight control, and latex stability were examined in detail. It was found that the Polysorbate 80 (Tween 80) and azodiisobutyronitrile gave the best exhibition in this system, polymer samples were got with narrow molecular‐weight dispersity (Mw/Mn = 1.1–1.2) and linear relationships of molecular weight versus monomer conversion, as well as a relatively low polydispersity index (<0.1). Through the GPC and SEM analysis, the polymerization processes under these conditions showed good living/control characteristics relative to the processes under normal emulsion polymerization, although the latex stability was susceptible to the CuBr2 catalyst. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012