Synthesis of telechelic oligostyrenes by the ozonoloysis of poly(styrene-stat-butadiene): Protection of styrene units against ozone attack by the use of Di-N-alkyl amides as sacrificial ozone scavengers

Rimmer, Stephen; Ebdon, John R.

doi:10.1002/(sici)1099-0518(199612)34:17<3573::aid-pola12>3.0.co;2-b

Cited by 20 publications

(13 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this paper, the synthesis of carboxy‐telechelic oligostyrene is studied with M n about 2000 g mol −1 . Several methods can lead to carboxy‐telechelic polystyrene (CTPS) 19–23. Carboxy‐terminated polystyrene can be prepared by end‐capping the polystyrene living anion with carbon dioxide.…”

Section: Introductionmentioning

confidence: 99%

“…He used chromatography on silica gel medium for the separation of functionalized polystyrenes, which are eluted in a methylcyclohexane/THF mixture. Rimmer and Ebdon23 synthesized telechelic oligostyrene with M n of 2000 g mol −1 by ozonolysis of poly(styrene‐ stat ‐butadiene). However, styrene must be protected against ozone attack by the use of di‐ N ‐alkylamides as sacrificial ozone scavengers.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Synthesis of carboxy‐terminated telechelic oligostyrenes by Dead End Polymerization

David¹,

Boutevin²,

Robin³

et al. 2002

Polymer International

View full text Add to dashboard Cite

Styrene was polymerized with 4,4′‐azobiscyanovaleric acid (ACVA) in order to obtain carboxy‐telechelic polystyrene (CTPS) using the Dead‐End Polymerization (DEP) conditions. First, we focused on experimental conditions leading to oligomers with molecular weights about 2000 g mol−1. Second, we demonstrated by‐products of ACVA radicals are also synthesized in the DEP conditions by combination or by disproportionation. The purification of CTPS was investigated in order to extract the by‐products of ACVA. An extraction of these by‐products in H2O pH 7 is suggested. Finally, the acid functionality of oligostyrene is evaluated by 1H NMR and conductimetric titrations. A functionality about 2 is obtained that confirmed the synthesis of CTPS. Copyright © 2002 Society of Chemical Industry

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Synthesis of carboxy‐terminated telechelic oligostyrenes by Dead End Polymerization

David¹,

Boutevin²,

Robin³

et al. 2002

Polymer International

View full text Add to dashboard Cite

show abstract

“…By performing a reduction with zinc and acetic acid, oligomers with aldehyde end groups (Scheme 1c) may be selectively produced. 22 Alternative pathways to Scheme 1 are discussed later.…”

Section: Resultsmentioning

confidence: 99%

“…The ozonolysis reaction was controlled for specific ozone exposure times, and reagents were used to produce oligomers with specific end groups. 22 MALDI-MS was used for mass analysis because of its extended mass range and ability to analyze both polar and nonpolar polymers. Oligomer distributions identified in the MALDI mass spectra were used to determine the microstructure (random vs block) and composition of monomers within the copolymer chain.…”

Section: Introductionmentioning

confidence: 99%

Microstructures of Butadiene Copolymers Determined by Ozonolysis/MALDI Mass Spectrometry

Zoller

Johnston

2000

Macromolecules

View full text Add to dashboard Cite

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry of ozonolysis degradation products was used to determine the microstructures of several butadiene copolymers. A random styrene−butadiene copolymer containing 45 wt % styrene was distinguished from a block (ABA) styrene−butadiene copolymer containing 38 wt % styrene. In addition, several acrylonitrile−butadiene copolymers with acrylonitrile contents ranging from 21 to 51 wt % were analyzed. The microstructures for the acrylonitrile−butadiene copolymers were confirmed to be fairly random. Quantitatively, the acrylonitrile compositions determined by ozonolysis/MALDI-MS were close to the reported values for these copolymers (typically within 5 wt %). The discrepancy between the reported and experimentally obtained compositions may be attributed, in part, to a composition bias arising from the ozonolysis process. A simple model for ozonolysis of a random copolymer was developed to investigate the effects of ozone exposure time on the oligomer distributions observed in the MALDI mass spectra.

show abstract

“…In our case, we have studied the synthesis of carboxy‐telechelic oligostyrene. Several methods can lead to carboxy‐telechelic polystyrene (PSCT) 13–17. Dead‐end polymerization (DEP) seems to be a good method for the synthesis of telechelic oligomers 18, 19.…”

Section: Introductionmentioning

confidence: 99%

Kinetic Evaluation of Cooperative [Co(salen)] Catalysts in the Hydrolytic Kinetic Resolution of rac‐Epichlorohydrin

et al. 2010

View full text Add to dashboard Cite

A wide variety of [Co(salen)] catalysts with different structures designed to enhance salen–salen cooperative interactions have been reported as catalysts for the hydrolytic kinetic resolution (HKR) of epoxides. However, the myriad catalysts have been evaluated under inconsistent experimental conditions, at different catalyst loadings, at different temperatures, with various epoxides and in several different laboratories, making rigorous comparisons between the catalysts impossible. To this end, 12 representative catalysts from our studies, as well as catalysts originally described by others, are reported in the HKR of epichlorohydrin under rigorously identical conditions. The comparison of the reactivity and selectivity of the different catalysts indicates that the soluble, oligomeric [Co(salen)] catalysts with cyclic frameworks impart the highest activity and enantioselectivity (>99 % ee, krel>99) in this representative reaction, requiring very short reaction times (<30 min), including the most active catalyst reported to date for the target reaction. In general, it is found that soluble polymer or oligomer‐supported catalysts are more active than insoluble supported catalysts under the conditions used. Among the insoluble catalysts, a polymer resin supported [Co(salen)] catalyst with excellent enantioselectivity (>99 % ee, krel>99) and medium reaction time (222 min), is the most active and selective of the class. The lessons demonstrated herein regarding design of active and selective catalysts offer useful insights into refining design strategies for other related cooperative catalytic reactions, suggesting emphases on catalyst flexibility and solubility under reaction conditions.

show abstract

Synthesis of telechelic oligostyrenes by the ozonoloysis of poly(styrene-stat-butadiene): Protection of styrene units against ozone attack by the use of Di-N-alkyl amides as sacrificial ozone scavengers

Cited by 20 publications

References 14 publications

Synthesis of carboxy‐terminated telechelic oligostyrenes by Dead End Polymerization

Synthesis of carboxy‐terminated telechelic oligostyrenes by Dead End Polymerization

Microstructures of Butadiene Copolymers Determined by Ozonolysis/MALDI Mass Spectrometry

Kinetic Evaluation of Cooperative [Co(salen)] Catalysts in the Hydrolytic Kinetic Resolution of rac‐Epichlorohydrin

Contact Info

Product

Resources

About