Diphenyl Phosphate as an Efficient Cationic Organocatalyst for Controlled/Living Ring-Opening Polymerization of δ-Valerolactone and ε-Caprolactone

Makiguchi, Kosuke; Satoh, Toshifumi; Kakuchi, Toyoji

doi:10.1021/ma200043x

Cited by 273 publications

(255 citation statements)

References 39 publications

Supporting

Mentioning

246

Contrasting

Unclassified

Order By: Relevance

“…7 Considerable effort has been directed toward the evaluation of various types of both organic acids/bases for the ROP of cyclic esters, 7-37 cyclic carbonates, [38][39][40][41][42][43] epoxides, [44][45][46][47] lactams, 48 cyclic (carbo)siloxanes, 49 cyclic phosphates, [50][51][52][53][54] etc. Regarding the ROP of cyclic esters, organic Brønsted acids, e.g., methane sulfonic acid (MSA) and triflimide, were found to be suited for the polymerization of lactones, [8][9][10][11][12][13][14][15][16][17][18][19] whereas organic bases, e.g., 1,8-diazadicyclo [5.4.0]undec-7-ene (DBU) and 4-dimethylaminopyridine (DMAP), were effective for the ROP of the lactide (LA). 7,[20][21][22][23][24]26 In addition, the bifunctional catalytic system possessing two activation sites for the monomer and propagating chain end also turned out to be effective for the ROP of ε-caprolactone (ε-CL) and LA.…”

Section: Introductionmentioning

confidence: 99%

Organophosphate-catalyzed bulk ring-opening polymerization as an environmentally benign route leading to block copolyesters, end-functionalized polyesters, and polyester-based polyurethane

et al. 2015

Self Cite

View full text Add to dashboard Cite

Abstract. The ring-opening polymerizations (ROPs) of ε-caprolactone (ε-CL), -varelolactone, 1,5-dioxepan-2-one, trimethylene carbonate, and L-lactide were performed in the bulk using an organophosphate, such as diphenyl phosphate, bis(4-nitrophenyl)phosphate, and di(2,6-xylyl)phosphate, as the catalyst. The ROPs proceeded in a well-controlled manner even in the bulk condition to afford well-defined aliphatic polyesters, polyester-ether, and polycarbonate with relatively low dispersities. Notably, the amount of the loaded catalyst was successfully reduced when compared to the conventional organophosphate-catalyzed ROP in solution. A kinetic study revealed the controlled/living nature of the present bulk ROP system, which allowed us to produce the block copolymers composed of polyesters, polyester-ether, and polycarbonate in one-pot. Syntheses of the end-functionalized poly(ε-caprolactone)s (PCLs) and poly(trimethylene carbonate) were successfully demonstrated using alcohol initiators possessing highly reactive functional groups. Furthermore, the α,ω-dihydroxy telechelic PCL-diol as well as the three-and four-armed star-shaped PCL-polyols were also easily obtained by using the polyols as an initiator. Finally, the one-pot synthesis of polyurethane via the ROP of ε-CL and subsequent urethane forming reaction was demonstrated by taking advantage of the dual catalytic abilities of the organophosphate for both the ROP and polyurethane synthesis.

show abstract

Section: Introductionmentioning

confidence: 99%

Organophosphate-catalyzed bulk ring-opening polymerization as an environmentally benign route leading to block copolyesters, end-functionalized polyesters, and polyester-based polyurethane

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

“…The targeted BCPs should have well-defined structures and narrow dispersities (Ð) in order to elucidate the pure cross-linking effect on the BCP properties. The diphenyl phosphate (DPP)-catalyzed ring-opening polymerization (ROP) of lactones has been known to be a robust and reliable method to produce well-defined aliphatic polyesters with a narrow Ð, 35 which let us employ this system for the synthesis of two PEG-b-P(CL-co-ACL) block copolymers with different PEG chain lengths.…”

Section: Resultsmentioning

confidence: 99%

A facile strategy for manipulating micellar size and morphology through intramolecular cross-linking of amphiphilic block copolymers

et al. 2017

Self Cite

View full text Add to dashboard Cite

The effect of intramolecular cross-linking in an amphiphilic block copolymer (BCP) system was systematically investigated in terms of its thermal properties, critical micelle concentration (CMC), and aqueous self-assembly. A series of linear BCPs consisting of poly(ethylene glycol) (PEG) as a hydrophilic block and poly(ε-caprolactone-co-7-allyloxepan-2-one) (P(CL-co-ACL)) as a hydrophobic block were prepared by the ring-opening copolymerization of ε-caprolactone (CL) and 7-allyloxepan-2-one (ACL) using poly(ethylene glycol) monomethyl ether as the initiator. The intramolecular olefin metathesis reaction in the P(CL-co-ACL) block was subsequently carried out under various conditions to prepare the cross-linked BCPs with different degrees of cross-linkings. The thermal analysis confirmed that the linear P(CL-co-ACL) block was found to crystallize, while the cross-linked one showed no crystallinity. In addition, the glass transition temperature of the P(CL-co-ACL) block increased upon the cross-linking. On the other hand, the intramolecular cross-linking had no significant influence on the CMC. The self-assembled micelles were prepared from the obtained BCPs and their size and morphology investigated.for the BCPs with relatively short PEG chains, the micellar size decreased from 36.6 nm to 16.7 nm as the degree of cross-linking of the P(CL-co-ACL) block increased. On the other hand, the BCPs with relatively long PEG chains showed a change in the micellar morphology from spherical micelles to short worm and large compound micelles upon the cross-linking.

show abstract

“…Kakuchi and colleagues 54 reported that DPP activates cyclic monomers, such as δ-valerolactone (VL) and ε-caprolactone (CL), to facilitate the nucleophilic attack of the alcoholic initiator and propagating end to produce the corresponding polymer, that is, poly (δ-valerolactone) (PVL) and poly(ε-caprolactone), respectively, via living polymerization.…”

Section: Topology-transformable Polymers T Takata and D Aokimentioning

confidence: 99%

Topology-transformable polymers: linear–branched polymer structural transformation via the mechanical linking of polymer chains

Takata

Aoki

2017

Polym J

View full text Add to dashboard Cite

In this review article, we discuss the synthesis and dynamic nature of macromolecular systems that have mechanically linked polymer chains capable of undergoing a topology transformation driven by a rotaxane molecular switch. The rotaxane linking of polymer chains plays a crucial role in these systems. A linear polymer possessing a crown ether/sec-ammonium salt-type [1] rotaxane moiety at the axle chain terminal was prepared via the rotaxane linking of a single polymer chain. A linear-cyclic polymer topology transformation was achieved via the movement of the wheel component from one end to the other end of the axle component using the rotaxane macromolecular switch function. The successful synthesis of a macromolecular [2]rotaxane (M2R) possessing a single polymer axle and one crown ether wheel led to a variety of unique applications, such as the development of topology-transformable polymers and the synthesis of rotaxane crosslinked polymers (RCPs). The introduction of a polymer chain to the wheel component of M2R (rotaxane linking of two polymer chains) produced a rotaxane-linked AB block copolymer that transformed its topology from linear to branched. Furthermore, a rotaxane-linked three-component polymer and an ABC triblock copolymer were synthesized and transformed to the corresponding 3-arm star (co)polymers, and the transformation was confirmed by measuring the hydrodynamic volume change. The structural transformation of 4-arm and 6-arm star polymers was also accomplished using the dynamic mobility of a similar rotaxane. As a useful application, M2R-based vinylic crosslinkers (RCs) were prepared and applied to the synthesis of RCPs, whereby the addition of RCs into radical polymerization systems of vinyl monomers afforded polymers with excellent toughness by enhancing both of tradeoff properties that cannot be achieved using typical covalent crosslinkers.

show abstract

Diphenyl Phosphate as an Efficient Cationic Organocatalyst for Controlled/Living Ring-Opening Polymerization of δ-Valerolactone and ε-Caprolactone

Cited by 273 publications

References 39 publications

Organophosphate-catalyzed bulk ring-opening polymerization as an environmentally benign route leading to block copolyesters, end-functionalized polyesters, and polyester-based polyurethane

Organophosphate-catalyzed bulk ring-opening polymerization as an environmentally benign route leading to block copolyesters, end-functionalized polyesters, and polyester-based polyurethane

A facile strategy for manipulating micellar size and morphology through intramolecular cross-linking of amphiphilic block copolymers

Topology-transformable polymers: linear–branched polymer structural transformation via the mechanical linking of polymer chains

Contact Info

Product

Resources

About