scholarly journals Heterogeneous Double Metal Cyanide Catalyzed Synthesis of Poly(ε-caprolactone) Polyols for the Preparation of Thermoplastic Elastomers

2021 ◽  
Author(s):  
Chinh Hoang Tran ◽  
Min Woong Lee ◽  
Sang Woo Park ◽  
Jae Eon Jeong ◽  
Soo Jeong Lee ◽  
...  
Keyword(s):  
Kinetic Studies ◽  
Thermoplastic Elastomers ◽  
Coordination Mechanism ◽  
Stress And Strain ◽  
Polypropylene Glycol ◽  
Telechelic Polymers ◽  
One Pot ◽  
Free Ring ◽  
Molecular Weights ◽  
Metal Cyanide

A series of polycaprolactones (PCLs) with molecular weights of 950–10,100 g mol−1 and Ð of 1.10–1.87 have been synthesized via one-pot, solvent-free ring-opening polymerization (ROP) of ε-caprolactone (CL) using a heterogeneous double metal cyanide (DMC) catalyst. Various initiators such as polypropylene glycol, ethylene glycol, propylene glycol, glycerol, and sorbitol are employed to tune the number of hydroxyl end groups and properties of the resultant PCLs. Kinetic studies indicate that the DMC-catalyzed ROP of CL proceeds via a coordination mechanism. Branched PCLs copolymers are also synthesized via the DMC-catalyzed copolymerization of CL with glycidol. The α,ω-hydroxyl functionalized PCLs were successfully used as telechelic polymers to produce thermoplastic poly(ester-ester) and poly(ester-urethane) elastomers with well-balanced stress and strain properties.

scholarly journals Heterogeneous Double Metal Cyanide Catalyzed Synthesis of Poly(ε-caprolactone) Polyols for the Preparation of Thermoplastic Elastomers

Catalysts ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1033
Author(s):  
Chinh-Hoang Tran ◽  
Min-Woong Lee ◽  
Sang-Woo Park ◽  
Jae-Eon Jeong ◽  
Soo-Jeong Lee ◽  
...  
Keyword(s):  
Kinetic Studies ◽  
Thermoplastic Elastomers ◽  
Stress And Strain ◽  
Polypropylene Glycol ◽  
Telechelic Polymers ◽  
One Pot ◽  
Coordination Polymerization ◽  
Free Ring ◽  
Molecular Weights ◽  
Metal Cyanide

A series of polycaprolactones (PCLs) with molecular weights of 950–10,100 g mol−1 and Ð of 1.10–1.87 have been synthesized via one-pot, solvent-free ring-opening polymerization (ROP) of ε-caprolactone (CL) using a heterogeneous double metal cyanide (DMC) catalyst. Various initiators, such as polypropylene glycol, ethylene glycol, propylene glycol, glycerol, and sorbitol, are employed to tune the number of hydroxyl end groups and properties of the resultant PCLs. Kinetic studies indicate that the DMC-catalyzed ROP of CL proceeds via a similar mechanism with the coordination polymerization. Branched PCLs copolymers are also synthesized via the DMC-catalyzed copolymerization of CL with glycidol. The α,ω-hydroxyl functionalized PCLs were successfully used as telechelic polymers to produce thermoplastic poly(ester-ester) and poly(ester-urethane) elastomers with well-balanced stress and strain properties.

scholarly journals Dual-initiating and living frustrated Lewis pairs: expeditious synthesis of biobased thermoplastic elastomers

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Yun Bai ◽  
Huaiyu Wang ◽  
Jianghua He ◽  
Yuetao Zhang ◽  
Eugene Y.-X. Chen
Keyword(s):  
Kinetic Studies ◽  
Thermoplastic Elastomers ◽  
Active Species ◽  
Chain Growth ◽  
Frustrated Lewis Pairs ◽  
One Pot ◽  
Acrylic Polymer ◽  
Step Procedure ◽  
Superior Mechanical Properties ◽  
Lewis Pairs

AbstractBiobased poly(γ-methyl-α-methylene-γ-butyrolactone) (PMMBL), an acrylic polymer bearing a cyclic lactone ring, has attracted increasing interest because it not only is biorenewable but also exhibits superior properties to petroleum-based linear analog poly(methyl methacrylate) (PMMA). However, such property enhancement has been limited to resistance to heat and solvent, and mechanically both types of polymers are equally brittle. Here we report the expeditious synthesis of well-defined PMMBL-based ABA tri-block copolymers (tri-BCPs)—enabled by dual-initiating and living frustrated Lewis pairs (FLPs)—which are thermoplastic elastomers showing much superior mechanical properties, especially at high working temperatures (80–130 °C), to those of PMMA-based tri-BCPs. The FLPs consist of a bulky organoaluminum Lewis acid and a series of newly designed bis(imino)phosphine superbases bridged by an alkyl linker, which promote living polymerization of MMBL. Uniquely, such bisphosphine superbases initiate the chain growth from both P-sites concurrently, enabling the accelerated synthesis of tri-BCPs in a one-pot, two-step procedure. The results from mechanistic studies, including the single crystal structure of the dually initiated active species, detailed polymerizations, and kinetic studies confirm the livingness of the polymerization and support the proposed polymerization mechanism featuring the dual initiation and subsequent chain growth from both P-sites of the superbase di-initiator.

scholarly journals Triblock polyester thermoplastic elastomers with semi-aromatic polymer end blocks by ring-opening copolymerization

2020 ◽  
Vol 11 (25) ◽  
pp. 6567-6581 ◽  
Author(s):  
Georgina L. Gregory ◽  
Gregory S. Sulley ◽  
Leticia Peña Carrodeguas ◽  
Thomas T. D. Chen ◽  
Alba Santmarti ◽  
...  
Keyword(s):  
Ring Opening ◽  
Thermoplastic Elastomers ◽  
One Pot ◽  
Aromatic Polymer ◽  
Better Than

A new series of block polyester thermoplastic elastomers are prepared by a one-pot procedure; they show properties competitive or better than conventional materials and can be fully degraded after use.

scholarly journals Impregnation of poly(L-lactide-ran-δ-valerolactone) with essential bark oil using supercritical carbon dioxide

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Chikara Tsutsumi ◽  
Souta Manabe ◽  
Susumu Nakayama ◽  
Yuushou Nakayama ◽  
Takeshi Shiono
Keyword(s):  
Carbon Dioxide ◽  
Supercritical Carbon Dioxide ◽  
Azeotropic Distillation ◽  
Proteinase K ◽  
High Yield ◽  
Feed Ratio ◽  
One Pot ◽  
Molecular Weights ◽  
Hydrolysis Process ◽  
Supercritical Carbon

Abstract This work studied the incorporation of essential bark oil from Thujopsis dolabrata var. hondae, which is known to repel various insects, in poly(L-lactide-ran-δ-valerolactone) [poly(L-LA-ran-VL)] using supercritical carbon dioxide (scCO2). The poly(L-LA-ran-VL) was synthesized by first purifying the monomers by azeotropic distillation with benzene, followed by polymerization with Sn(oct)2 using the same equipment, representing an efficient one-pot process. The copolymerization of L-LA with VL using this technique at a feed ratio of 90/10 mol/mol gave poly(L-LA-ran-VL) (91/9) with a molecular weight of 6.48 × 104 g/mol and a high yield of 74.9%. Products with molecular weights over 5.0 × 104 g/mol were obtained at L-LA feed proportions of 70 to 90%. Impregnation trials were conducted between 40 and 120 °C at 14 MPa for 3 h. The oil content of a 73/27 specimen was found to increase significantly during processing at 100 or 120 °C. During enzymatic degradation with proteinase K, the 91/9 specimen showed the fastest degradation rate. Although the 71/29 sample was slowly hydrolyzed in a phosphate buffer at pH 7.0, the release of oil vapor from this material was slightly higher than that from the 91/9 specimen, and the vapor release rate continuously increased throughout the hydrolysis process.

Regio-selective synthesis of polyepichlorohydrin diol using Zn–Co(iii) double metal cyanide complex

RSC Advances ◽  
2014 ◽  
Vol 4 (42) ◽  
pp. 21765-21771 ◽  
Author(s):  
Ren-Jian Wei ◽  
Ying-Ying Zhang ◽  
Xing-Hong Zhang ◽  
Bin-Yang Du ◽  
Zhi-Qiang Fan
Keyword(s):  
Heterogeneous Catalyst ◽  
Bulk Polymerization ◽  
Selective Synthesis ◽  
Cyanide Complex ◽  
One Pot ◽  
Metal Cyanide

This work describes the first regio-selective synthesis of poly(epichlorohydrin) diol via a simple one-pot bulk polymerization with a heterogeneous catalyst.

scholarly journals High Yielding Flow Synthesis of a Macrocyclic Molecular Hinge

2021 ◽  
Author(s):  
Christopher Jones ◽  
Laurence J. Kershaw Cook ◽  
David Marquez-Gamez ◽  
Konstantin V. Luzyanin ◽  
Jonathan Steed ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Continuous Flow ◽  
Kinetic Studies ◽  
Molecular Machines ◽  
High Dilution ◽  
Fluoride Ions ◽  
One Pot ◽  
Flow Synthesis ◽  
Single Isomer ◽  
Molecular Hinge

ABSTRACT: Many molecular machines are built from modular components with well-defined motile capabilities, such as axles and wheels. Hinges are particularly useful, as they provide the minimum flexibility needed for a simple and pronounced conformational change. Compounds with multiple stable conformers are common, but molecular hinges almost exclusively operate via dihedral rotations rather than truly hinge-like clamping mechanisms. An ideal molecular hinge would better reproduce the behavior of hinged devices, such as gates and tweezers, while remaining soluble, scalable and synthetically versatile. Herein, we describe two isomeric macrocycles with clamp-like open and closed geometries, which crystallize as separate polymorphs but interconvert freely in solution. An unusual one-pot addition cyclization reaction was used to produce the macrocycles on a multigram scale from inexpensive reagents, without supramolecular templating or high-dilution conditions. Using mechanistic information from NMR kinetic studies and at-line mass spectrometry, we developed a semi-continuous flow synthesis with maximum conversions of 85-93% and over 80% selectivity for a single isomer. The macrocycles feature voids that are sterically protected from guests, including reactive species such as fluoride ions, and could therefore serve as chemically inert hinges for adaptive supramolecular receptors and flexible porous materials.

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