The poly(propylene oxide-co-ethylene oxide) gradient is controlled by the polymerization method: determination of reactivity ratios by direct comparison of different copolymerization models

2019 ◽  
Vol 10 (22) ◽  
pp. 2863-2871 ◽  
Author(s):  
Jan Blankenburg ◽  
Erik Kersten ◽  
Kamil Maciol ◽  
Manfred Wagner ◽  
Sirus Zarbakhsh ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Ethylene Oxide ◽  
Propylene Oxide ◽  
Reactivity Ratios ◽  
H Nmr ◽  
Poly Propylene ◽  
Polymerization Method

An investigation of the copolymerization of EO and PO by in situ1H NMR spectroscopy reveals striking differences in the monomer gradient, depending on the polymerization method.

Copolymerization of two bromine containing methacrylate monomers with methylmethacrylate. Determination of reactivity ratios by in situ quantitative 1H NMR monitoring

e-Polymers ◽  
2007 ◽  
Vol 7 (1) ◽  
Author(s):  
Ichim Ionut Cameliu ◽  
Marius Ciprian Rusu ◽  
Mihai Rusu ◽  
Popa Marcel ◽  
Christelle Delaite ◽  
...  
Keyword(s):  
Side Chain ◽  
Random Structure ◽  
Reactivity Ratios ◽  
Medical Implants ◽  
Propyl Methacrylate ◽  
H Nmr ◽  
Methacrylate Monomers ◽  
Methacrylic Monomers

AbstractAn important method used to make medical implants radiologically visible is based on introduction of radiopaque bromine or iodine containing methacrylic monomers. Thus, 2-(2-bromopropionyloxy) propyl methacrylate (BPPM) and 2-(2-bromoisobutyryloxy) propyl methacrylate (BIPM) were synthesized with the aim to use them as radiopaque agents. The free radical initiated copolymerization of BPPM and BIPM with methyl methacrylate (MMA) were performed directly in a thermostatic cell of the NMR spectrometer. The copolymer compositions obtained from 1H NMR spectra led to the determination of the reactivity ratios (rMMA = 1.08 ± 0.12; rBPPM = 1.01 ± 0.13 and rMMA = 0.95 ± 0.09; rBIPM = 0.95 ± 0.1). The reactivity ratios of these two monomers is similar to that of MMA suggesting that the length of the bromine containing monomers side chain does not affect significantly the reactivity of the methacrylic double bond. From the results we conclude the copolymers to have random structure.

Determination of reactivity ratios for the anionic copolymerization of ethylene oxide and propylene oxide in bulk

1991 ◽  
Vol 27 (7) ◽  
pp. 573-579 ◽  
Author(s):  
Frank Heatley ◽  
Ga-er Yu ◽  
Colin Booth ◽  
Trevor G. Blease
Keyword(s):  
Ethylene Oxide ◽  
Propylene Oxide ◽  
Reactivity Ratios ◽  
Anionic Copolymerization

Determination of Monomer Reactivity Ratios in the Copolymerization of Ethylene Oxide and Propylene Oxide

1994 ◽  
Vol 31 (1) ◽  
pp. 9-11
Author(s):  
M. Adal ◽  
P. Flodin ◽  
E. Gottberg-Klingskog ◽  
K. Holmberg
Keyword(s):  
Ethylene Oxide ◽  
Propylene Oxide ◽  
Reactivity Ratios ◽  
Monomer Reactivity Ratios

Phase behaviour and structure of amphiphilic poly(ethylene oxide)-poly(propylene oxide) triblock copolymers ((EO)4(PO)59(EO)4 and (EO)17(PO)59(EO)17) in ternary mixtures with water and xylene

2003 ◽  
Vol 81 (8) ◽  
pp. 897-908 ◽  
Author(s):  
Pius Kipkemboi ◽  
Ali Khan ◽  
Björn Lindman ◽  
Viveka Alfredsson
Keyword(s):  
Ethylene Oxide ◽  
Propylene Oxide ◽  
Liquid Crystalline ◽  
Triblock Copolymers ◽  
Phase Behaviour ◽  
Ternary Mixtures ◽  
H Nmr ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Poly Propylene

The isothermal ternary phase behaviour and structure of amphiphilic copolymer–water–xylene systems was investigated for two poly(ethylene oxide)–poly(propylene oxide) (PEO–PPO) triblock copolymers, (EO)4(PO)59(EO)4 and (EO)17(PO)59(EO)17, at 25°C. The phase boundaries were identified using 2H NMR and inspection under polarized light. The microstructure and structural length scales in the lyotropic liquid crystalline phases were determined and characterized by small-angle X-ray scattering. The amounts and relative proportions of the selective solvents can modulate the resulting microstructures, although the phase sequence observed depends on the relative PEO–PPO block ratio. A variety of lyotropic liquid crystalline (LLC) phases are thermodynamically stable in the system with copolymer (EO)17(PO)59(EO)17, both of the normal ("oil-in-water") and of the reverse ("water-in-oil") morphology. The high hydrophobic content of copolymer (EO)4(PO)59(EO)4, however, favours reverse LLC structures with low interfacial curvature. No normal LLC phases are formed by this system.Key words: amphiphilic, triblock copolymers, poly(ethylene oxide), poly(propylene oxide), ternary mixtures, phase behaviour, lyotropic liquid crystals, SAXS, 2H NMR.

Thermoresponsive Core−Shell Brush Copolymers with Poly(propylene oxide)-block-poly(ethylene oxide) Side Chains via a “Grafting from” Technique

2010 ◽  
Vol 43 (4) ◽  
pp. 1771-1777 ◽  
Author(s):  
Junpeng Zhao ◽  
Grigoris Mountrichas ◽  
Guangzhao Zhang ◽  
Stergios Pispas
Keyword(s):  
Ethylene Oxide ◽  
Propylene Oxide ◽  
Core Shell ◽  
Side Chains ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Grafting From ◽  
Poly Propylene

Carbon-13 NMR determination of poly(propylene oxide) microstructure

1986 ◽  
Vol 19 (5) ◽  
pp. 1337-1343 ◽  
Author(s):  
Frederic C. Schilling ◽  
Alan E. Tonelli
Keyword(s):  
Propylene Oxide ◽  
Poly Propylene
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