Microemulsion Polymerization of Styrene:  The Effect of Salt and Structure

Full, A. P.; Kaler, Eric W.; Arellano, Jesús; Puig, J. E.

doi:10.1021/ma951103i

Cited by 85 publications

(104 citation statements)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(12) by use of Eq. (6) to yield Thus, the total number of polymer particles, NT is given by Average diameter of polymer particles electron microscope is given by…”

Section: Total Number Of Polymer Particlesmentioning

confidence: 99%

A new kinetic interpretation of the styrene microemulsion polymerization

Nomura

Suzuki

1997

Macro Chemistry & Physics

View full text Add to dashboard Cite

The polymerization of styrene initiated by potassium peroxodisulfate was conducted at 50 "C in oil-in-water microemulsions using sodium lauryl sulfate and 1-pentanol as emulsifier and cosurfactant, respectively. Based on the experimental findings that both particle size and molecular weight of the polymers are almost independent of styrene conversion and the initial initiator concentration, a kinetic scheme of the microemulsion polymerization of styrene is proposed, which assumes that (1) particle nucleation occurs in monomer-swollen micelles and almost all the radicals in the water phase enter the monomerswollen micelles and finally initiate polymerization therein, ( 2 ) with negligible radical termination in the water phase and (3) with negligible radical entry into the preformed polymer particles, and accordingly, (4) all chain-stopping events in the active polymer particles are chain transfer reactions to monomer. Based on this kinetic scheme, a simple kinetic model is proposed, which can explain fairly well the progress of styrene microemulsion polymerization in the initial stage.

show abstract

“…(12) by use of Eq. (6) to yield Thus, the total number of polymer particles, NT is given by Average diameter of polymer particles electron microscope is given by…”

Section: Total Number Of Polymer Particlesmentioning

confidence: 99%

A new kinetic interpretation of the styrene microemulsion polymerization

Nomura

Suzuki

1997

Macro Chemistry & Physics

View full text Add to dashboard Cite

show abstract

“…It is well established that microemulsion polymerizations predominantly takes place in microemulsified droplets. 16,17 The observed negligible difference in the locus and feed concentrations of monomers in microemulsions resulted in the true reactivity ratio matching the apparent value (Table III). Because of the close solubility and polarity of the monomers, there should not be any preferential site of polymerization within a droplet.…”

Section: Resultsmentioning

confidence: 82%

Recalculation of the monomer reactivity and experimental differences in emulsion and microemulsion copolymerizations of partially water‐soluble monomers

Bhawal

Devi

2002

J of Applied Polymer Sci

View full text Add to dashboard Cite

On the basis of the copolymerization data for the emulsion and microemulsion polymerizations of ethyl acrylate and methyl methacrylate, the monomer concentrations at the copolymerization loci were calculated, with the assumption that the sum of their concentrations at the polymerization loci was equal to unity. The equivalency of the locus and feed concentrations, as for styrene, was invalid because of the partial water solubility of both the monomers. Consequently, the locus concentration rather than the initial feed concentration was used to recalculate the monomer reactivity at the actual site of polymerization, and this was called the true reactivity ratio. The apparent reactivity ratios for emulsion and bulk polymerizations were different, whereas those for microemulsion and bulk polymerizations were similar. This difference was attributed to the mode of polymerization in the emulsions and microemulsions, leading to different copolymer compositions for similar initial feed concentrations. This was verified experimentally from the thermal properties and particle size distribution measurements.

show abstract

“…exhaustive purification was not performed. This contrasts strongly from the influence of salts on standard microemulsions where a decreased particle size with increasing amounts of salt is found [23]. Table 3 summarizes the systems used for the present examination including their ion exchange grade.…”

mentioning

confidence: 86%

The first crystalline hexagonal Si₃N₄ microtubes

1996

View full text Add to dashboard Cite

Experimental exchange" lelramethylammonium 339.54 92 DS telrae~ylammonlum 395.65 99 dimethyldiethanolammonium 399.60 90 telrabutylammonium 507.86 96Synthesis of surfactants with diverse organic counterions: Cetyltrimethylammonium chloride (Aldrich) and sodium dodecylsulfate (Serva) were used as supplied. The sodium salts of propionic acid, hydroxybutyric acid, oxalic acid, fumaric acid, maleic acid, terephthalic acid, tartaric acid, and citric acid (all Aldrich) were made by neutralization of a 5 wt.-% acid solution in water with sodium hydroxide. The aqueous solutions of the salts were used as stock solutions. Tetramethylammonium chloride, tetraethylammonium chloride hydrate, and tetrabutylammonium chloride hydrate (Aldrich) were also used as supplied. Diethanoldimethylammonium chloride was synthesized by quarternation of dimethylethanolamine.The surfactants with organic counterions were made by extraction processes. Because the solid-liquid extraction turned out to be rather ineffective for removal of the inorganic salt from the double organic salts, a liquidliquid extraction procedure was performed. For this procedure, stoichiometric amounts of the appropriate organic salts including the targeted counterion were dissolved in a 25 wt-% aqueous solution of the surfactants SDS or CTMA-CI, and 2-butanol was added step-wise until phase separation occurrcd. After separation of the phases, the lower aqueous phase was removed. Repeated addition of small amounts of 2-butanol to the organic phase caused repeated phase separation, until the remainder contained little double inorganic salt, and precipitation stopped. The double organic surfactant was isolated by evaporation of the solvent under reduced pressure. This purification procedure was repeated until the residual amounts of inorganic salt were insignificant. Depending on the hydrophilicity of the organic counterions, ion exchange ratios between 81 % and 99 YO were obtained, as determined by 'H-measurements. Since purity turned out not to be critical for the resulting particle sizes (microemulsions made with the same surfactant with 80-95% purity produced the same particle size, higher salt loads increased the particle size). exhaustive purification was not performed. This contrasts strongly from the influence of salts on standard microemulsions where a decreased particle size with increasing amounts of salt is found [23]. Table 3 summarizes the systems used for the present examination including their ion exchange grade. CTMA-propanoate CTMA.-oxalale CTMA,-terephthalale CTMA-yhydroxvbuwrate CTMAdarfrate CTMA,-maleate CTMA,-fumarate

show abstract

Microemulsion Polymerization of Styrene: The Effect of Salt and Structure

Cited by 85 publications

References 49 publications

A new kinetic interpretation of the styrene microemulsion polymerization

A new kinetic interpretation of the styrene microemulsion polymerization

Recalculation of the monomer reactivity and experimental differences in emulsion and microemulsion copolymerizations of partially water‐soluble monomers

The first crystalline hexagonal Si₃N₄ microtubes

Contact Info

Product

Resources

About

Microemulsion Polymerization of Styrene: The Effect of Salt and Structure

Cited by 85 publications

References 49 publications

A new kinetic interpretation of the styrene microemulsion polymerization

A new kinetic interpretation of the styrene microemulsion polymerization

Recalculation of the monomer reactivity and experimental differences in emulsion and microemulsion copolymerizations of partially water‐soluble monomers

The first crystalline hexagonal Si3N4 microtubes

Contact Info

Product

Resources

About

The first crystalline hexagonal Si₃N₄ microtubes