Tailored Melting Temperatures and Crystallinity of Poly(ethylene oxide) Induced by Designed Chain Defects

2019 ◽  
Vol 1 (11) ◽  
pp. 3130-3136
Author(s):  
Muhammad Haris Samiullah ◽  
Martin Pulst ◽  
Yury Golitsyn ◽  
Aaron Bui ◽  
Karsten Busse ◽  
...  
Keyword(s):  
Ethylene Oxide ◽  
Melting Temperatures ◽  
Chain Defects ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Isothermal Thickening and Thinning Processes in Low Molecular Weight Poly(ethylene oxide) Fractions Crystallized from the Melt. 5. Effect of Chain Defects

1996 ◽  
Vol 29 (27) ◽  
pp. 8816-8823 ◽  
Author(s):  
Seung-Wook Lee ◽  
Erqiang Chen ◽  
Anqiu Zhang ◽  
Yeocheol Yoon ◽  
Bong Seok Moon ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Ethylene Oxide ◽  
Low Molecular Weight ◽  
Chain Defects ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene

Solid State Phase Transitions in Poly(ethylene oxide) Crystals Induced by Designed Chain Defects

2018 ◽  
Vol 51 (11) ◽  
pp. 4407-4414 ◽  
Author(s):  
Muhammad Haris Samiullah ◽  
Martin Pulst ◽  
Yury Golitsyn ◽  
Karsten Busse ◽  
Silvio Poppe ◽  
...  
Keyword(s):  
Phase Transitions ◽  
Solid State ◽  
Ethylene Oxide ◽  
Chain Defects ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Oxide Crystals

The Structure of Radiation Cross-Linked Poly (ethylene oxide) Gels

1971 ◽  
Vol 29 ◽  
pp. 76-77
Author(s):  
C. E. Cluthe ◽  
G. G. Cocks
Keyword(s):  
Molecular Weight ◽  
Ethylene Oxide ◽  
Parallel Plate ◽  
Average Molecular Weight ◽  
Radical Reaction ◽  
Free Radical Reaction ◽  
Nitrogen Gas ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Initial Viscosity

Aqueous solutions of a 1 weight-per cent poly (ethylene oxide) (PEO) were degassed under vacuum, transferred to a parallel plate viscometer under a nitrogen gas blanket, and exposed to Co60 gamma radiation. The Co60 source was rated at 4000 curies, and the dose ratewas 3.8x105 rads/hr. The poly (ethylene oxide) employed in the irradiations had an initial viscosity average molecular weight of 2.1 x 106.The solutions were gelled by a free radical reaction with dosages ranging from 5x104 rads to 4.8x106 rads.

Preparation of Organized Mesoporous Silica from Sodium Metasilicate Solutions in Alkaline Medium Using Nonionic Surfactants

2003 ◽  
Vol 68 (10) ◽  
pp. 2019-2031 ◽  
Author(s):  
Markéta Zukalová ◽  
Jiří Rathouský ◽  
Arnošt Zukal
Keyword(s):  
Mesoporous Silica ◽  
Ethylene Oxide ◽  
Sodium Metasilicate ◽  
Spherical Particles ◽  
Structure Directing Agent ◽  
Inorganic Species ◽  
Poly Ethylene Oxide ◽  
Acidic Conditions ◽  
Poly Ethylene ◽  
Hydrolysis Of

A new procedure has been developed, which is based on homogeneous precipitation of organized mesoporous silica from an aqueous solution of sodium metasilicate and a nonionic poly(ethylene oxide) surfactant serving as a structure-directing agent. The decrease in pH, which induces the polycondensation of silica, is achieved by hydrolysis of ethyl acetate. Owing to the complexation of Na+ cations by poly(ethylene oxide) segments, assembling of the mesostructure appears to occur under electrostatic control by the S0Na+I- pathway, where S0 and I- are surfactant and inorganic species, respectively. As the complexation of Na+ cations causes extended conformation of poly(ethylene oxide) segments, the pore size and pore volume of organized mesoporous silica increase in comparison with materials prepared under neutral or acidic conditions. The assembling of particles can be fully separated from their solidification, which results in the formation of highly regular spherical particles of mesoporous silica.

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