A new PDMS macromonomer stabilizer for dispersion polymerization of styrene in supercritical carbon dioxide

Wang, Ruolei; Cheung, H. Michael

doi:10.1002/app.20476

Cited by 26 publications

(13 citation statements)

References 13 publications

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“…2 the PMMA obtained in this process are shown, exhibiting the spherical shape of the particles, consistent with previous works found in the literature [1,2,5,9,10]. According to Wang and Cheung [13], the stabilizer concentration controls the morphology of the polymer. The polymerization process led to PMMA particles ranging from 11.57 mm to 72.27 mm when using 5.4% w/w of stabilizing agent, and from 19.1 mm to 46.73 mm when using 7.02% w/w of stabilizing agent.…”

Section: Resultssupporting

confidence: 87%

Dispersion polymerization of methyl methacrylate in supercritical carbon dioxide using vinyl terminated poly(dimethylsiloxane)

Oliveira

Machado

Barth

et al. 2016

Chemical Engineering and Processing: Process Intensification

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A B S T R A C TPMMA has applications on the medical, pharmaceutical and engineering areas. Different processes may be employed for its production. Here, MMA polymerization was performed by supercritical carbon dioxide dispersion. CO 2 is inert, easily retrievable and separated from the product. The monomer is soluble in dense CO 2 , unlike PMMA, requiring a stabilizer to maintain the dispersion. Here, vinyl terminated PDMS was used as a dispersing agent. The reactions were conducted at 16 MPa/80 C for 4 h. Product characterization was performed by SEM, to evaluate the morphology at estimate the particle size, SEC, to determine the molar mass and polydispersion index, 1 H NMR and FTIR spectroscopy, in order to verify the chemical structure of the product, and also gravimetric analyses, to determine the residual monomer. The results confirmed the adequacy of the process and of the stabilizer for PMMA particles production.

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Section: Resultssupporting

confidence: 87%

Dispersion polymerization of methyl methacrylate in supercritical carbon dioxide using vinyl terminated poly(dimethylsiloxane)

Oliveira

Machado

Barth

et al. 2016

Chemical Engineering and Processing: Process Intensification

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“…This phenomenon was also observed in other stabilizer systems. [7][8][9][10]13,16,20 The particle size of PMMA synthesized using GMA-PDMS stabilizer was similar with the size of PMMA prepared with fluoro and fluoro copolymer stabilizer, which had a range of 2-5 µm. 8,12,13,15,16 Effect of Initiator Concentration.…”

Section: Resultsmentioning

confidence: 99%

GMA-functionalized reactive stabilizer for polymerization of methyl methacrylate in supercritical CO2: effect of stabilizer, initiator and monomer concentrations

2008

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Glycidyl methacrylate linked poly(dimethylsiloxane) (GMA-PDMS) was synthesized and used as a stabilizer for the dispersion polymerization of methyl methacrylate (MMA) in supercritical CO 2 . This study examined the effect of the concentrations of the stabilizer, 2,2'-azobisisobutyronitrile (AIBN) initiator, and MMA on the yield, molecular weight, and morphology of the poly(methyl methacrylate) (PMMA) product. PMMA was obtained in 94.6% yield using only 0.87 wt% GMA-PDMS. When the AIBN concentration was increased from 0.25 to 1.06 wt%, the molecular weight and particle size of the PMMA decreased from 56,600 to 21,600 and from 4.1 to 2.7 µm, whereas the particle size distribution increased from 1.3 to 1.9. The M n of the PMMA product ranged from 41,600 and 55,800 under typical polymerization conditions. The PMMA particle diameter ranged from 1.8 to 11.0 µm and the particle size distribution ranged from 1.4 to 1.8.

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“…Since Shaffer et al 16 used poly(dimethylsiloxane) monomethacrylate as a surfactant for polymerization of MMA and styrene in supercritical CO 2 , PDMS macromonomers have been widely used as a reactive stabilizer for the dispersion polymerization in liquid and supercritical CO 2 . For instance, commercially supplied PDMS macromonomers, such as PDMS monomethacrylate, 7,14,[16][17][18][19] monocarbinol-terminated PDMS, 14 PDMS-g-pyrrolidone carboxylic acid, 6 methacryloxypropyl-terminated PDMS, 20 and vinyldimethylsiloxy PDMS, 21 were used for the dispersion polymerization of MMA and styrene. Instead of using commercially available macromonomer stabilizer, Giles et al synthesized a PDMS monomethacrylate surfactant from hexamethylcyclotrisiloxane and 3-(methacryloxy)propyldimethylchlorosilane using a lithium catalyst.…”

Section: Introductionmentioning

confidence: 99%

Polymerization of methyl methacrylate in carbon dioxide using glycidyl methacrylate linked reactive stabilizer: Effect of pressure, reaction time, and mixing

2009

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Using glycidyl methacrylate-linked poly(dimethylsiloxane), methyl methacrylate was polymerized in supercritical CO 2 . The effects of CO 2 pressure, reaction time, and mixing on the yield, molecular weight, and molecular weight distribution (MWD) of the poly(methyl methacrylate) (PMMA) products were investigated. The shape, number average particle diameter, and particle size distribution (PSD) of the PMMA were characterized. Between 69 and 483 bar, the yield and molar mass of the PMMA products showed a trend of increasing with increasing CO 2 pressure. However, the yield leveled off at around 345 bar and the particle diameter of the PMMA increased until the pressure reached 345 bar and decreased thereafter. With increasing pressure, MWD became more uniform while PSD was unaffected. As the reaction time was extended at 207 bar, the particle diameter of PMMA decreased at 0.48 ± 0.03% AIBN, but increased at 0.25% AIBN. Mixing the reactant mixture increased the PMMA yield by 18.6% and 9.3% at 138 and 207 bar, respectively.

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A new PDMS macromonomer stabilizer for dispersion polymerization of styrene in supercritical carbon dioxide

Cited by 26 publications

References 13 publications

Dispersion polymerization of methyl methacrylate in supercritical carbon dioxide using vinyl terminated poly(dimethylsiloxane)

Dispersion polymerization of methyl methacrylate in supercritical carbon dioxide using vinyl terminated poly(dimethylsiloxane)

GMA-functionalized reactive stabilizer for polymerization of methyl methacrylate in supercritical CO2: effect of stabilizer, initiator and monomer concentrations

Polymerization of methyl methacrylate in carbon dioxide using glycidyl methacrylate linked reactive stabilizer: Effect of pressure, reaction time, and mixing

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