Theoretical and experimental studies of the initiator influence on the anionic ring opening polymerization of propylene oxide

Cendejas, Gabriel; Flores-Sandoval, César A.; Huitrón, Nelson; Rubio, Herrera; Zamudio‐Rivera, Luis S.; Beltrán, Hiram I.; Vázquez, F.

doi:10.1016/j.molstruc.2007.08.023

Cited by 18 publications

(20 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1. It comprises four stages: (1) initiator preparation, (2) polymerization of a central block of propylene oxide (Cendejas et al, 2008), (3) polymerization of ethylene oxide side sequences, and (4) functionalization of the triblock copolymer.…”

Section: Synthesismentioning

confidence: 99%

Experimental and theoretical study of bifunctionalized PEO–PPO–PEO triblock copolymers with applications as dehydrating agents for heavy crude oil

Flores-Sandoval

Castro

Flores

et al. 2017

Arabian Journal of Chemistry

View full text Add to dashboard Cite

A series of a,x-diamines of polyoxyethylene-polyoxypropylene-polyoxyethylene (POE-POP-POE) triblock copolymer was synthesized and experimentally evaluated as dewatering agents for heavy crude oil. A quantitative structure-activity relationship (QSAR) study of the effect of the secondary amine structure over the yield of nucleophilic substitution reactions with a,x-ditosylate ester of PEO-PPO-PEO triblock copolymer was performed exclusively at the DFT level. Multiple linear regression (MLR) analysis including softness or hardness parameters gave R 2 = 0.9062, producing an equation with an acceptable r 2 mðtestÞ value. Furthermore, in order to understand the physicochemical interaction between the functionalizing copolymers and water, QSAR models

show abstract

Section: Synthesismentioning

confidence: 99%

Experimental and theoretical study of bifunctionalized PEO–PPO–PEO triblock copolymers with applications as dehydrating agents for heavy crude oil

Flores-Sandoval

Castro

Flores

et al. 2017

Arabian Journal of Chemistry

View full text Add to dashboard Cite

show abstract

“…They are mostly applied as nonionic amphiphilic surfactants or polyether polyols for synthesis of polyurethanes (PU) [1][2][3][4][5][6][7][8] [7][8][9]. However, high molar mass poly(propylene oxide)s cannot be prepared by anionic polymerization because of an extensive chain transfer reaction to the monomer leading to the formation of macromolecules with allyloxy starting groups 4 which can isomerize to cis-propylenoxy ones 5 (Scheme 1) [10][11][12].…”

Section: Introductionmentioning

confidence: 99%

The influence of initiator and macrocyclic ligand on unsaturation and molar mass of poly(propylene oxide)s prepared with various anionic system

et al. 2017

View full text Add to dashboard Cite

Anionic polymerization of propylene oxide was carried out in the presence of two groups of potassium salts activated 18-crown-6 (18C6), e.g. alkoxide salts (CH 3 OK, i-PrOK, t-BuOK, CH 3 OCH 2 CH(CH 3 )OK, KCH 2 O) and other salts (CbK, Ph 3 CK, Ph 2 PK, Ph 3 HBK, KK, KH, and [(CH 3 ) 3 Si] 2 NK) in THF at room temperature. Application of various initiating systems results in polyethers which are different in level and kind of unsaturation represented by allyloxy, cis-and trans-propenyloxy, as well as vinyloxy starting groups. In the presence of selected initiator, i.e. t-BuO -K ? unsaturation increases markedly by addition of 18C6 or C222. During the initiation step oxirane ring-opening and direct deprotonation of the monomer occur simultaneously involving in some cases also the ligand. All initiators opens oxirane ring in the b-position except i-PrOK, which opens it in the b-and a-position. The mechanisms of the reactions were discussed.

show abstract

“…[1][2][3] They are mainly synthesized by anionic ring opening polymerization (AROP) of PO using typical initiators as alkali metal hydroxides [4,5] or alkoxides. [6][7][8][9] However, it is impossible to obtain high molar mass polymers by this method because of the side reaction, i.e., chain transfer to the monomer resulting in macromolecules with allyloxy starting groups and macromolecules with hydroxyl end groups. [10][11][12][13][14] In the Submitted presence of anhydrous potassium hydroxide [4] or potassium 1-methoxy-2-propoxide [6] the allyloxy groups isomerize to cis-propenyloxy groups.…”

Section: Introductionmentioning

confidence: 99%

“…Initiation of PO polymerization with compounds containing at least two active sites is particularly interesting because such systems are used in the synthesis of triblock copolymers with wide applications as surfactants. [9] The polyether diols with M n ¼ 2000-4000 g/mol are used especially in the synthesis of very elastic linear polyurethanes (thermoplastic elastomers) in reactions with diisocyanates. [2] Polyurethane elastomers are applied for fabrication of shoe soles, sealants, coatings, and fibers.…”

Section: Introductionmentioning

confidence: 99%

Application of Dipotassium Glycoxides–Activated 18-Crown-6 for the Synthesis of Poly(propylene oxide) with Increased Molar Mass

Grobelny

Matlengiewicz

Golba

et al. 2014

International Journal of Polymer Analysis and Characterization

View full text Add to dashboard Cite

Mono-and dipotassium salts of dipropylene glycol were applied for the polymerization of propylene oxide in mild conditions, i.e., tetrahydrofuran solution at ambient temperature. The structure of polymers was investigated by use of 13 C NMR and MALDI-TOF techniques. The structure depends strongly on the kind of initiator and additives that are used such as coronand 18-crown-6 and dipropylene glycol. The lowest unsaturation, represented by allyloxy starting groups, has the polymer obtained by use of monopotassium salt without the ligand. The highest unsaturation degree is for the polymer synthesized in the presence of dipotassium salt-activated 18-crown-6. This polymer, obtained at high initial monomer concentration and low initial concentration of initiator, consists of two fractions, i.e., a low molar mass fraction (M n ¼ 9400) containing mainly macromolecules with alkoxide starting and end groups and a much higher molar mass fraction (M n ¼ 29500 g/mol) containing macromolecules with allyloxy starting groups and alkoxide or hydroxyl end groups. Addition of free glycol to this system decreases the molar mass of polymers. Similar results were obtained by use of dipotassium salts of other glycols. The mechanisms of the studied processes are discussed.

show abstract

Theoretical and experimental studies of the initiator influence on the anionic ring opening polymerization of propylene oxide

Cited by 18 publications

References 14 publications

Experimental and theoretical study of bifunctionalized PEO–PPO–PEO triblock copolymers with applications as dehydrating agents for heavy crude oil

Experimental and theoretical study of bifunctionalized PEO–PPO–PEO triblock copolymers with applications as dehydrating agents for heavy crude oil

The influence of initiator and macrocyclic ligand on unsaturation and molar mass of poly(propylene oxide)s prepared with various anionic system

Application of Dipotassium Glycoxides–Activated 18-Crown-6 for the Synthesis of Poly(propylene oxide) with Increased Molar Mass

Contact Info

Product

Resources

About