Dispersion polymerization of styrene in ethanol-water media: Monomer partitioning behavior and locus of polymerization

Lacroix‐Desmazes, Patrick; Guillot, J.

doi:10.1002/(sici)1099-0488(19980130)36:2<325::aid-polb11>3.0.co;2-j

Cited by 43 publications

(21 citation statements)

References 8 publications

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“…As the monomer concentration and initiator concentration became low at higher conversion, the molecular weight decreased slightly and the molecular weight distribution became even wider. Similar trends of molecular weight and its distribution can also be seen in other dispersion polymerization systems reported by Lu, [9] Lacroix-Desmazes, [10,18] Liu et al [14] . It should be noted that the broadening of molecular weight distribution in this case of MAn/VAc copolymerization may be also resulted from the chain transfer either on VAc monomer or the copolymer (VAc unit).…”

Section: Molecular Weight and Its Distributionsupporting

confidence: 83%

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Stabilizer‐Free Dispersion Copolymerization of Maleic Anhydride and Vinyl Acetate. II. Polymerization Features

Xing

Yang

2006

Macro Chemistry & Physics

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Summary: The polymerization features of the novel stabilizer‐free dispersion copolymerization of MAn and VAc were studied. It was found that the dispersion copolymerization of MAn/VAc is a fairly rapid process, which starts from a slow solution polymerization (below 10% conversion, Stage I) and follows a drastic increase of polymerization rate (10–80% conversion, Stage II) due to the known gel effect. Such process was accompanied by the increase of molecular weight of the copolymer formed ($\overline M _{\rm n}$ from 1.2 × 104 to 3.8 × 104 g · mol−1) and the broadening of the molecular weight distribution ($\overline M _{\rm w} /\overline M _{\rm n}$ from 2.4 to 8.0). Ea of Stage I was determined to be 76.7 kJ · mol−1, while the value of Stage II was 64.7 kJ · mol−1. The lower Ea in Stage II than that in Stage I suggests that there exists a shift of polymerization locus from the solution phase to the particle phase. Moreover, we found that the initial rate of polymerization increased with monomer concentration as well as initiator concentration, following the relationship (Rp)i ∝ [MAn + VAc] · [BPO]. This further implies that the dispersion copolymerization mainly proceeds as a solution polymerization in the very early stage.Evolutions of the stabilizer‐free dispersion copolymerization of MAn and VAc with butyl acetate as reaction medium and the solution copolymerization with methyl propyl ketone as solvent.magnified imageEvolutions of the stabilizer‐free dispersion copolymerization of MAn and VAc with butyl acetate as reaction medium and the solution copolymerization with methyl propyl ketone as solvent.

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Section: Molecular Weight and Its Distributionsupporting

confidence: 83%

“…[10] The mechanism and kinetic events in the dispersion polymerization have been successfully clarified by this model. Another major contribution to the mechanism of dispersion polymerization was made by Paine, [11] who proposed a semi-quantitative model based on the coagulative nucleation principle.…”

Section: Introductionmentioning

confidence: 99%

Stabilizer‐Free Dispersion Copolymerization of Maleic Anhydride and Vinyl Acetate. II. Polymerization Features

Xing

Yang

2006

Macro Chemistry & Physics

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“…On the other hand, larger particles capture dead polymer, which terminated in the continuous phase, with a lower molecular weight typical of solution polymerization. 9 In accordance with these assumptions and if the toluene/alcohol ratio was kept constant, smallest poly(HEMA) particles were formed under otherwise identical conditions from a mixture toluene/3-methylbutan-1-ol, since 3-methylbutan-1-ol has the lowest value of the solubility parameter (20.5 MPa 1/2 ) of all the used alcohols. On the other hand, since butan-2-ol has the highest solubility parameter (22.1 MPa 1/2 ), the particles formed from its mixture with toluene were the largest.…”

Section: Effect Of Solvent Systemmentioning

confidence: 92%

Effect of reaction parameters on the particle size in the dispersion polymerization of 2-hydroxyethyl methacrylate

Horák

1999

J. Polym. Sci. A Polym. Chem.

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Poly(2‐hydroxyethyl methacrylate) particles in the micron size range were obtained by the dispersion polymerization. Cellulose acetate butyrate and dibenzoyl peroxide were used as steric stabilizer and initiator, respectively. The ultimate particle size could be adjusted by the selection of a suitable polymerization medium consisting of an alcohol added to toluene and by varying their relative amounts. The particle size increased with increasing solubility parameter of the mixture, i.e., by decreasing the toluene/2‐methylpropan‐1‐ol, toluene/butan‐2‐ol, and toluene/3‐methylbutan‐1‐ol ratio. The particle size decreased with increasing concentration of the stabilizer and/or initiator. At the same time, the particle size distribution became narrower. Particles prepared from polymerization mixtures purged with nitrogen before the start of polymerization were smaller, and of narrower distribution, than those prepared from nitrogen‐non‐purged mixtures. Equilibrium swelling of particles in toluene decreased with the decreasing content of toluene in the polymerization mixture. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3785–3792, 1999

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“…It determines the solubility of all the components in the reaction mixture, as well as the particle size, the monomer partitioning coefficient between the continuous phase and the particle phase [28,29], and therefore also the kinetics of polymerization. The effects of the solvent will be discussed in more detail in a following paper.…”

Section: Ratio Of Meoh/h 2 Omentioning

confidence: 99%

Preparing of monodisperse and cation-charged polystyrene particles stabilized with polymerizable quarternary ammonium by dispersion polymerization in a methanol–water medium

Zhang

Bai

et al. 2009

Journal of Colloid and Interface Science

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Dispersion polymerization of styrene in ethanol-water media: Monomer partitioning behavior and locus of polymerization

Cited by 43 publications

References 8 publications

Stabilizer‐Free Dispersion Copolymerization of Maleic Anhydride and Vinyl Acetate. II. Polymerization Features

Stabilizer‐Free Dispersion Copolymerization of Maleic Anhydride and Vinyl Acetate. II. Polymerization Features

Effect of reaction parameters on the particle size in the dispersion polymerization of 2-hydroxyethyl methacrylate

Preparing of monodisperse and cation-charged polystyrene particles stabilized with polymerizable quarternary ammonium by dispersion polymerization in a methanol–water medium

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