Synthesis of highly syndiotactic polymers by discrete catalysts or initiators

Miyake, Garret M.; Chen, Eugene Y.‐X.

doi:10.1039/c1py00245g

Cited by 34 publications

(17 citation statements)

References 168 publications

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“…The glass transition temperatures (T g ) of extracted PMMA, determined from the mid-point of the glass transition in the heat flow curves (vide infra), were observed between 98 and 100°C from both polymerized emulsion and emulsion gel samples. These T g 's are in consistent with the observations for the PMMA with similar tacticities [17,33]. The glass transition was primarily a reversing transition: the intensity of the reversing heat flow was much larger than that of the non-reversing heat flow.…”

Section: Thermal Analysissupporting

confidence: 88%

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Low-temperature polymerization of methyl methacrylate emulsion gels through surfactant catalysis

Tan

Regev

et al. 2016

Journal of Colloid and Interface Science

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Section: Thermal Analysissupporting

confidence: 88%

“…Polymerizations of MMA at low temperatures not only allowed the retention of the activity of immobilized biomolecules during and after the polymerization, but it also enhanced the thermal properties of the resulting materials [6,17]. In this paper, we extend our prior work on the low temperature polymerization of styrene to MMA [9].…”

Section: Introductionmentioning

confidence: 91%

Low-temperature polymerization of methyl methacrylate emulsion gels through surfactant catalysis

Tan

Regev

et al. 2016

Journal of Colloid and Interface Science

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“…In contrast, Hatada et al primarily reported the synthesis of an isotactic PMMA ( mm > 95%) with a narrow molecular weight distribution by anionic polymerization using tert ‐butylmagnesium bromide prepared in diethyl ether,4 and developed anionic catalyst systems by combining alkyllithium with bulky organoaluminum compounds 5,6. For the radical polymerization, Okamoto et al reported the stereospecific synthesis of PMMA by free‐radical polymerizations using Sc(OTf) 3 or fluoroalcohols at low temperature 7–11. Matyjaszewski and coworkers revealed stereospecific systems, such as the reversible addition‐fragmentation chain transfer polymerization and the copper(I)‐catalyzed atom transfer radical polymerization (ATRP) of MMA 12.…”

Section: Introductionmentioning

confidence: 99%

Synthesis of syndiotactic‐rich star‐shaped poly(methyl methacrylate) by core‐first group transfer polymerization using N‐(trimethylsilyl)bis(trifluoromethanesulfonyl)imide

Chen

Takada

Fuchise

et al. 2012

J. Polym. Sci. A Polym. Chem.

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The N‐(trimethylsilyl)bis(trifluoromethanesulfonyl)imide‐catalyzed (Me3SiNTf2‐catalyzed) group transfer polymerization (GTP) of methyl methacrylate (MMA) has been studied for synthesizing stereospecific star‐shaped poly(methyl methacrylate)s (PMMAs). The catalytic property of Me3SiNTf2 for the GTP of MMA using 1‐methoxy‐1‐trimethylsilyloxy‐2‐methyl‐propene as the initiator was confirmed by a kinetic investigation and matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry measurement. The initiating efficiency (f) of Me3SiNTf2 was 0.94–1.00, which was estimated by the value of Mn(calcd)/Mn(SEC). The Me3SiNTf2‐catalyzed GTP of MMA was carried out using initiators possessing three, four, and six MTS groups (MTS3, MTS4, and MTS6, respectively) under the condition of [MMA]0/[MTS3, MTS4, or MTS6]0 = 120 at −55 °C. All the obtained PMMAs exhibited unimodal and narrow molecular weight distributions as Mw/Mns = 1.03–1.04 and the Mw(MALS)s of the 3‐, 4‐, and 6‐armed star‐shaped PMMAs (PMMA3, PMMA4, and PMMA6, respectively) were 12.9, 12.9, and 13.4 kgmol−1, respectively, which fairly agreed with the calculated Mw(calcd) values. The syndiotacticities, rrs, of PMMA3, PMMA4, and PMMA6 were in the range of 87–89%. The stereoblock synthesis of PMMA3, PMMA4, and PMMA6 was performed by the first and second polymerizations at −55 and 45 °C; the rrs of the first and second PMMA blocks were 87.0, 87.0, and 86.0% and 65.0, 65.0, and 64.0%, respectively. The glass transition temperatures (Tgs) were 118.1, 115.8, and 111.5 °C for the respective syndiotactic‐rich PMMA3, PMMA4, and PMMA6 and 111.5, 109.7, and 107.6 °C for the respective stereoblock ones. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

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“…Especially in the case of group 4, these new catalysts and cocatalyst/activators have achieved great success in the production of advanced polyolefin materials [4]. The new systems are able to control product molecular weight, polydispersity, comonomer enchainment level and pattern, the tacticity of poly(a-olefins) [17,56,57], copolymerization of olefins with polar comonomers (group 10) [54,55,[58][59][60][61][62], and the catalytic synthesis of block copolymers by processes such as chain shuttling polymerization [63][64][65][66][67].…”

Section: Introductionmentioning

confidence: 99%

Supported Single-Site Organometallic Catalysts for the Synthesis of High-Performance Polyolefins

2014

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Single-site organometallic catalysts supported on solid inorganic or organic substrates are making an important contribution to heterogeneous catalysis. Early and late transition metal single-site catalysts have changed the polyolefin manufacturing industry and research with their ability to produce polymers with unique properties. Moreover, several of these catalysts have been commercialized on a large scale. Their heterogenization for slurry or gas phase olefin polymerization is important to produce polyolefin as beads and to avoid reactor fouling. The large majority of supports currently used in industry are inorganic materials (SiO 2 , Al 2 O 3 , MgCl 2 ), with silica being the most important. Single-site supported catalysts are most commonly prepared by molecular-level anchoring/chemisorption, in which a molecular precursor undergoes reaction with the surface while maintaining most of the ligand sphere of the parent molecule. Chemisorption of discrete organometallic complexes on solid supports yields catalysts with well-defined active sites, greater thermal stability than the homogeneous analogues, and decreased reactor fouling versus the homogeneous analogues. This review presents a detailed account of the synthesis, characterization and polymerization properties of single-site catalysts supported on metal oxides and metal sulfated oxides, primarily carried out at Northwestern University.

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Synthesis of highly syndiotactic polymers by discrete catalysts or initiators

Cited by 34 publications

References 168 publications

Low-temperature polymerization of methyl methacrylate emulsion gels through surfactant catalysis

Low-temperature polymerization of methyl methacrylate emulsion gels through surfactant catalysis

Synthesis of syndiotactic‐rich star‐shaped poly(methyl methacrylate) by core‐first group transfer polymerization using N‐(trimethylsilyl)bis(trifluoromethanesulfonyl)imide

Supported Single-Site Organometallic Catalysts for the Synthesis of High-Performance Polyolefins

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