scholarly journals Confined organization of fullerene units along high polymer chains

2013 ◽  
Vol 1 (36) ◽  
pp. 5747 ◽  
Author(s):  
Lei Fang ◽  
Peng Liu ◽  
Benjamin R. Sveinbjornsson ◽  
Sule Atahan-Evrenk ◽  
Koen Vandewal ◽  
...  
Keyword(s):  
Polymer Chains ◽  
High Polymer

scholarly journals Drastic Enhancement of Carbon Dioxide Adsorption in Fluoroalkyl-Modified Poly(allylamine)

2021 ◽  
Author(s):  
Athanasios Koutsianos ◽  
Louise B. Hamdy ◽  
Chun-Jae Yoo ◽  
Jason J. Lee ◽  
Marco Taddei ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Hydrogen Bonding ◽  
Room Temperature ◽  
Polymer Chains ◽  
High Polymer ◽  
Carbon Dioxide Adsorption ◽  
Positron Annihilation Lifetime ◽  
Gas Streams ◽  
Amine Hydrogen ◽  
Amine Content

Polyamine-based carbon dioxide sorbents suffer from a seesaw relationship between amine content and amine efficiency. High polyamine loadings equate to increased amine contents, but often at the expense of amine efficiency. Carbon dioxide mass transport in compact polymers is severely limited, especially at ambient temperature. High polymer contents curtail diffusion pathways, hindering CO2 from reaching and reacting with the numerous amine functions. Here, we overcome this issue using poly(allylamine) (PAA) grafted with short fluoroalkyl chains and then cross-linked with C60. As experimentally evidenced by positron annihilation lifetime spectroscopy, the incorporation of fluoroalkyl chains generates free volume elements that act as additional diffusion pathways within the material. The inclusion of void volume in fluoroalkyl-functionalized PAA sorbents results in radically increased CO2 uptakes and amine efficiencies in diluted gas streams at room temperature, including simulated air. We speculate that the hydrophobic fluorinated functions interfere with the strong amine hydrogen bonding network disrupting and consequently altering the packing and conformation of the polymer chains. The evidence presented here is a blueprint for the development of more efficient amine-based CO2 sorbents

scholarly journals Drastic Enhancement of Carbon Dioxide Adsorption in Fluoroalkyl-Modified Poly(allylamine)

2021 ◽  
Author(s):  
Athanasios Koutsianos ◽  
Louise B. Hamdy ◽  
Chun-Jae Yoo ◽  
Jason J. Lee ◽  
Marco Taddei ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Hydrogen Bonding ◽  
Room Temperature ◽  
Polymer Chains ◽  
High Polymer ◽  
Carbon Dioxide Adsorption ◽  
Positron Annihilation Lifetime ◽  
Gas Streams ◽  
Amine Hydrogen ◽  
Amine Content

Polyamine-based carbon dioxide sorbents suffer from a seesaw relationship between amine content and amine efficiency. High polyamine loadings equate to increased amine contents, but often at the expense of amine efficiency. Carbon dioxide mass transport in compact polymers is severely limited, especially at ambient temperature. High polymer contents curtail diffusion pathways, hindering CO2 from reaching and reacting with the numerous amine functions. Here, we overcome this issue using poly(allylamine) (PAA) grafted with short fluoroalkyl chains and then cross-linked with C60. As experimentally evidenced by positron annihilation lifetime spectroscopy, the incorporation of fluoroalkyl chains generates free volume elements that act as additional diffusion pathways within the material. The inclusion of void volume in fluoroalkyl-functionalized PAA sorbents results in radically increased CO2 uptakes and amine efficiencies in diluted gas streams at room temperature, including simulated air. We speculate that the hydrophobic fluorinated functions interfere with the strong amine hydrogen bonding network disrupting and consequently altering the packing and conformation of the polymer chains. The evidence presented here is a blueprint for the development of more efficient amine-based CO2 sorbents

The Mechanical Feature and Dependence of the pH-Sensitive Hydrogel

2011 ◽  
Vol 213 ◽  
pp. 479-482
Author(s):  
Xiu Fang Zhu ◽  
Ming Yang ◽  
Hong Xia Zhang ◽  
Yu Jing Nie
Keyword(s):  
Ionic Strength ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Tensile Tests ◽  
Polymer Chains ◽  
High Polymer ◽  
Microstructure Change ◽  
Mechanical Feature ◽  
Swelling Equilibrium ◽  
Different Levels

Tensile tests were conducted on poly (AAc-co-AAm) hydrogel sensitive to variations in environmental pH and ionic strength. Mechanical properties (Young’s modulus) were determined at different levels of swelling equilibrium. The results show that there are great shift in the modulus number between the swollen and unswollen states, corresponding to the maximum, the Young’s modulus data in the pH7 buffers is a decrease of 80%. The Poisson’s ratio of the samples tested in the pH2 with 1.0M ionic strength solution is nearly 0.5, which implying its incompressibility. Analyzing its inner structure, the reason may be the high polymer chains entangled highly, they can resist the deformation. The further investigations of SEM micrographs prove our suggestions about the microstructure change.

scholarly journals Vibrational Spectra of High Polymer Chains

1967 ◽  
Vol 88 (2) ◽  
pp. 111-124 ◽  
Author(s):  
Tatsuo MIYAZAWA
Keyword(s):  
Vibrational Spectra ◽  
Polymer Chains ◽  
High Polymer

Shape of Confined Polymer Chains

1997 ◽  
Vol 7 (3) ◽  
pp. 433-447 ◽  
Author(s):  
C. E. Cordeiro ◽  
M. Molisana ◽  
D. Thirumalai
Keyword(s):  
Polymer Chains ◽  
Confined Polymer ◽  
Confined Polymer Chains

Dynamics of polymer chains trapped in a slit

1977 ◽  
Vol 38 (10) ◽  
pp. 1285-1291 ◽  
Author(s):  
F. Brochard
Keyword(s):  
Polymer Chains

SuFExable Polymers with Helical Structures Derived from Thionyl Tetrafluoride (SOF4)

2019 ◽  
Author(s):  
Suhua Li ◽  
Gencheng Li ◽  
Bing Gao ◽  
Sidharam P. Pujari ◽  
Xiaoyan Chen ◽  
...  
Keyword(s):  
Functional Polymers ◽  
Polymer Chains ◽  
New Materials ◽  
Helical Structures ◽  
Polymer Backbone ◽  
Silyl Ethers ◽  
Helical Polymer ◽  
Key Characteristics ◽  
Post Modification ◽  
Individual Polymer

The first SuFEx click chemistry synthesis of SOF<sub>4</sub>-derived copolymers based upon the polymerization of bis(iminosulfur oxydifluorides) and bis(aryl silyl ethers) is described. This novel class of SuFEx polymer presents two key characteristics: First, the newly created [-N=S(=O)F-O-] polymer backbone linkages are themselves SuFExable and primed to undergo further high-yielding and precise SuFEx-based post-modification with phenols or amines to yield branched functional polymers. Second, studies of individual polymer chains of several of these new materials indicate the presence of helical polymer structures, which itself suggests a preferential approach of new monomers onto the growing polymer chain upon the formation of the stereogenic linking moiety.

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