A Catalytic Approach for Cationic Living Polymerization:  Sc(OTf)<sub>3</sub>-Catalyzed Ring-Opening Polymerization of Lactones

Nomura, Nobuyoshi; Taira, Atsuko; Tomioka, Takashi; Okada, Masahiko

doi:10.1021/ma991580r

Cited by 120 publications

(101 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…According to a previous report dealing with Sc(OTf) 3 , 10 we did freeze drying to remove absorption water on the scandium catalyst. PS-Sc and benzene were added in a 10-mL round bottom flask.…”

Section: Ring-opening Polymerization Of E-caprolactone Catalyzed By Pmentioning

confidence: 99%

“…1 Metal complexes are the most commonly explored catalysts; they include tin, 2,3 aluminum, [4][5][6][7] iron, 8,9 scandium, [10][11][12] yittrium, 13,14 zinc, 15,16 bismuth, 17 ruthenium, 18 zirconocene, 19 and so on. A popular polymerization system for PCL is ring-opening polymerization (ROP) of ecaprolactone catalyzed by organotin compound.…”

Section: Introductionmentioning

confidence: 99%

“…Recently, it was found that PCL is synthesized by ROP of e-caprolactone catalyzed by Sc(OTf) 3 , and that the ROP proceeds in a quasi-living manner. 10,11 In fact, Sc(OTf) 3 is attractive as a water-stable Lewis acid because of its low hydrolysis constant and high exchange rate constant, 29 and has other advantages: (1) lower toxicity, (2) supressed transesterification, 27 and (3) recyclibility. However, the recovery procedure is time-consuming and needs tedious washing and extraction with water, thereby producing aqueous waste containing organic solvent.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Controlled ring‐opening polymerization of ε‐caprolactone using polymer‐supported scandium catalyst

Takasu

Oshimura

Hirabayashi

2008

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

Section: Ring-opening Polymerization Of E-caprolactone Catalyzed By Pmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Controlled ring‐opening polymerization of ε‐caprolactone using polymer‐supported scandium catalyst

Takasu

Oshimura

Hirabayashi

2008

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

“…10,12 Recently Kobayashi et al insisted that rare earth metal triflates such as Sc(OTf) 3 can be used as an intriguing Lewis acid catalyst in organic synthesis. 13 Successful ring-opening polymerization (ROP) of CL using Sc(OTf) 3 was firstly reported by Nomura et al, showing the formation of PCL with very narrow molecular distribution even at 25 • C. 14 Furthermore Sc(OTf) 3 as † To whom correspondence should be addressed.…”

mentioning

confidence: 99%

Coupling Reaction of Two Kinds of Molecular-Weight Controlled Biodegradable Polymers

Zhou¹,

Kaga²,

Takasu³

et al. 2003

Polym J

View full text Add to dashboard Cite

ABSTRACT:Poly(ε-caprolactone) (PCL) having controlled molecular weight was synthesized by ring opening polymerization of ε-caprolactone (CL) initiated by ethanol with stannous(II) octanoate or scandium(III) trifluoromethane sulfonate as a catalyst. The hydroxyl end group of the resulting polymer was converted to trimethylsiloxyl group by using hexamethyldisilazane. On the other hand, poly(vinyloxy-t-butyldimethylsilane) (PVOTBDMS) was obtained by aldoltype of group transfer polymerization. Under the presence of ZnBr 2 or TiCl 4 as the catalyst, the coupling reaction of above two precursor polymers was carried out so as to build PCL-block-PVOTBDMS with controlled molecular weight and narrow molecular weight distribution. The PCL-block-PVA as the final goal could be obtained by elimination of the silyl groups in the above block copolymer.KEY WORDS Biodegradable Copolymer / Block Copolymer / Aldol-GTP / Poly(vinyloxy-tbutyldimethylsilane) / Poly(ε-caprolactone) / Living Ring-Opening Polymerization / In recent years, biodegradable polymers have attracted more and more attention from many fields to replace the traditional polymers owing to the increasing environmental problems caused by polymer disposal after use. It has been reported that they can be efficiently degraded into non-toxic water-soluble oligomers by a great number of living cells or microorganisms widely inhabited in the natural environment, then the water-soluble oligomers can be reutilized in many ways and finally changed into water, carbon dioxide or methane through several metabolic procedures of microorganisms. [1][2][3][4][5] It is well known that aliphatic polyesters are the most promising class of biodegradable materials which can be prepared by biosynthesis and chemical process 6-8 such as polycondensation and ring-opening polymerization.Poly(ε-caprolactone) (PCL) is one of the wellstudied aliphatic polyesters, which can be easily synthesized by CL with ethanol as an initiator and stannous(II) octanoate (Sn(Oct) 2 ) as a catalyst. 9-11 Up to present, Sn(Oct) 2 and aluminum triisopropoxide (Al(Oi-Pr) 3 ) have been most conventional catalysts for the ring-opening polymerization of lactones. 10, 12 Recently Kobayashi et al. insisted that rare earth metal triflates such as Sc(OTf) 3 can be used as an intriguing Lewis acid catalyst in organic synthesis. 13 Successful ring-opening polymerization (ROP) of CL using Sc(OTf) 3 was firstly reported by Nomura et al., showing the formation of PCL with very narrow molecular distribution even at 25

show abstract

“…23,24 Thus, it seems that the presence of substituents in LA ring is mainly responsible for slowing down the rate of propagation by ACE mechanism to the extent that it cannot compete with AM propagation even at conditions when [LA] ) [HOA].…”

mentioning

confidence: 99%

Mechanism of propagation in the cationic polymerization of L,L‐lactide

Baśko

Kubisa

2008

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

Cationic ring‐opening polymerization of oxygen‐containing heterocycles may proceed either by active chain end (ACE) mechanism or by activated monomer (AM) mechanism for which the presence of terminal HO group is required. Typically, ACE mechanism is favored. Cationic polymerization of L,L‐lactide seems to be an exception. In the absence of HO containing compounds, polymerization can be initiated only by strong protic acids generating terminal HO group and allowing polymerization by AM mechanism.

show abstract

A Catalytic Approach for Cationic Living Polymerization: Sc(OTf)₃-Catalyzed Ring-Opening Polymerization of Lactones

Cited by 120 publications

References 16 publications

Controlled ring‐opening polymerization of ε‐caprolactone using polymer‐supported scandium catalyst

Controlled ring‐opening polymerization of ε‐caprolactone using polymer‐supported scandium catalyst

Coupling Reaction of Two Kinds of Molecular-Weight Controlled Biodegradable Polymers

Mechanism of propagation in the cationic polymerization of L,L‐lactide

Contact Info

Product

Resources

About

A Catalytic Approach for Cationic Living Polymerization: Sc(OTf)3-Catalyzed Ring-Opening Polymerization of Lactones

Cited by 120 publications

References 16 publications

Controlled ring‐opening polymerization of ε‐caprolactone using polymer‐supported scandium catalyst

Controlled ring‐opening polymerization of ε‐caprolactone using polymer‐supported scandium catalyst

Coupling Reaction of Two Kinds of Molecular-Weight Controlled Biodegradable Polymers

Mechanism of propagation in the cationic polymerization of L,L‐lactide

Contact Info

Product

Resources

About

A Catalytic Approach for Cationic Living Polymerization: Sc(OTf)₃-Catalyzed Ring-Opening Polymerization of Lactones