Characterization of low-molar-mass polymers by gradient polymer elution chromatography

1997 ◽  
Vol 775 (1-2) ◽  
pp. 157-177 ◽  
Author(s):  
H.J.A Philipsen ◽  
M Oestreich ◽  
B Klumperman ◽  
A.L German
Keyword(s):  
Molar Mass ◽  
Elution Chromatography

Development and Characterization of Amine-Clay Hybrid Adsorbents for CO2 Capture

2016 ◽  
Vol 1133 ◽  
pp. 547-551 ◽  
Author(s):  
Ali E.I. Elkhalifah ◽  
Mohammad Azmi Bustam ◽  
Azmi Mohd Shariff ◽  
Sami Ullah ◽  
Nadia Riaz ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Surface Area ◽  
Surface Properties ◽  
Molar Mass ◽  
Adsorption Ability ◽  
Stepwise Increase ◽  
Inverse Effect ◽  
Bet Method ◽  
Sodium Form

The present work aims at a better understanding of the influences of the intercalated mono-, di- and triethanolamines on the characteristics and CO2 adsorption ability of sodium form of bentonite (Na-bentonite). The results revealed that the molar mass of intercalated amines significantly influenced the structural and surface properties as well as the CO2 adsorption capacity of Na-bentonite. In this respect, a stepwise increase in the d-spacing of Na-bentonite with the molar mass of amine was recorded by XRD technique. However, an inverse effect of the molar mass of amine on the surface area was confirmed by BET method. CO2 adsorption experiments on amine-bentonite hybrid adsorbents showed that the CO2 adsorption capacity inversly related to the molar mass of amine at 25 ͦC and 101 kPa. Accordingly, Na-bentonite modified by monoethanolammonium cations adsorbed as high as 0.475 mmol CO2/g compared to 0.148 and 0.087 mmol CO2/g for that one treated with di- and triethanolammonium cations, respectively.

scholarly journals Molar mass determination of lignins and characterization of their polymeric structures by multi-detector gel permeation chromatography

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Evamaria C. Gaugler ◽  
Wolfgang Radke ◽  
Andrew P. Vogt ◽  
Dawn A. Smith
Keyword(s):  
Molar Mass ◽  
Lithium Bromide ◽  
Gel Permeation Chromatography ◽  
Mass Determination ◽  
Organosolv Lignin ◽  
Gel Permeation ◽  
Softwood Kraft Lignin ◽  
Polymeric Structures

AbstractMolar masses, Mark-Houwink-Sakurada (MHS) exponents, and refractive index increments (dn/dc) for three lignins were determined without derivatization by multi-detector gel permeation chromatography (GPC) in dimethylformamide (DMF) with 0.05 M lithium bromide (LiBr). The lack of effectiveness of fluorescence filters on molar mass determination by GPC-multi-angle laser light scattering (MALS) was confirmed for softwood kraft lignin (Indulin AT) and revealed for mixed hardwood organosolv lignin (Alcell) as well as soda straw/grass lignin (Protobind 1000). GPC with viscometry detection confirmed that these lignins were present as compact molecules. The MHS exponent α for Indulin AT and Alcell was in the order of 0.1. Additionally, the intrinsic viscosity of Protobind 1000 for a given molar mass was much lower than that of either Alcell or Indulin AT. This is the first report of dn/dc values for these three lignins in DMF with 0.05 M LiBr.

A qualitative study to the influence of molar mass on retention in gradient polymer elution chromatography (GPEC)

1996 ◽  
Vol 110 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Bert Klumperman ◽  
Paul Cools ◽  
Harry Philipsen ◽  
Wim Staal
Keyword(s):  
Qualitative Study ◽  
Molar Mass ◽  
Elution Chromatography

Thermal, Mechanical and Magneto-Mechanical Characterization of Liquid Crystalline Elastomers Loaded with Iron Oxide Nanoparticles

2015 ◽  
Vol 1718 ◽  
pp. 3-7
Author(s):  
Stephany Herrera-Posada ◽  
Barbara O. Calcagno ◽  
Aldo Acevedo
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Liquid Crystalline ◽  
Molar Mass ◽  
Oxide Nanoparticles ◽  
Magnetic Actuation ◽  
Scanning Calorimetry ◽  
Elastomeric Matrix ◽  
Alternating Magnetic Fields

ABSTRACTLiquid crystalline elastomers (LCEs) are materials that reveal unusual mechanical, optical and thermal properties due to their molecular orientability characteristic of low molar mass liquid crystals while maintaining the mechanical elasticity distinctive of rubbers. As such, they are considered smart shape-changing responsive systems. In this work, we report on the preparation of magnetic sensitized nematic LCEs using iron oxide nanoparticles with loadings of up to 0.7 wt%. The resultant thermal and mechanical properties were characterized by differential scanning calorimetry, expansion/contraction experiments and extensional tests. The magnetic actuation ability was also evaluated for the neat elastomer and the composite with 0.5 wt% magnetic content, finding reversible contractions of up to 23% with the application of alternating magnetic fields (AMFs) of up to 48 kA/m at 300 kHz. Thus, we were able to demonstrate that the inclusion of magnetic nanoparticles yields LCEs with adjustable properties that can be tailored by changing the amount of particles embedded in the elastomeric matrix, which can be suitable for applications in actuation, sensing, or as smart substrates.

Molar Mass Characterization of Crude Lignosulfonates by Asymmetric Flow Field-Flow Fractionation

2018 ◽  
Vol 7 (1) ◽  
pp. 216-223 ◽  
Author(s):  
Irina Sulaeva ◽  
Philipp Vejdovszky ◽  
Ute Henniges ◽  
Arnulf Kai Mahler ◽  
Thomas Rosenau ◽  
...  
Keyword(s):  
Flow Field ◽  
Molar Mass ◽  
Field Flow Fractionation ◽  
Asymmetric Flow ◽  
Flow Fractionation

scholarly journals Synthesis and Characterization of a Multifunctional Conjugated Polymer

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Emerson C. G. Campos ◽  
Cristiano Zanlorenzi ◽  
Bruno F. Nowacki ◽  
Gabriela M. Miranda ◽  
Denis A. Turchetti ◽  
...  
Keyword(s):  
Conjugated Polymer ◽  
Molar Mass ◽  
Photophysical Properties ◽  
Gel Permeation Chromatography ◽  
Thermal Characterization ◽  
Polymer Structure ◽  
Synthesis And Characterization ◽  
Metallic Ions ◽  
Scanning Calorimetry

This work reports the synthesis and characterization of a conjugated polymer based on fluorene and terpyridine, namely, poly[(9,9-bis(3-((S)-2-methylbutylpropanoate))fluorene-alt-6,6′-(2,2′:6′,2′′-terpyridin-6-yl)] (LaPPS71). The structure was characterized by 1H and 13C nuclear magnetic resonance (NMR) and Fourier-transform infrared (FTIR) spectroscopy. The molar mass was measured by gel permeation chromatography (GPC). As thermal characterization, the glass transition temperature (Tg) was measured by differential scanning calorimetry (DSC). The polymer structure contains two sites capable of complexation with metallic ions, affording the possibility of obtainment of independent or electronically coupled properties, depending on the complexation site. The photophysical properties were fully explored in solution and solid state, presenting ideal results for the preparation of various metallopolymers, in addition to potential application as a metamaterial, due to the presence of the chiral center in the side chains of the polymer.

Molecular weight and contraction factors of hyperbranched poly(urea-urethane)s

e-Polymers ◽  
2006 ◽  
Vol 6 (1) ◽  
Author(s):  
Albena Lederer ◽  
Mona Abd Elrehim ◽  
Falko Schallausky ◽  
Dieter Voigt ◽  
Brigitte Voit
Keyword(s):  
Chemical Structure ◽  
Molar Mass ◽  
Molecular Shape ◽  
Branched Polymers ◽  
Compact Structure ◽  
H Nmr ◽  
Hyperbranched Poly ◽  
End Groups ◽  
Solution Behaviour

AbstractElution fractionations of broadly molar mass-distributed, hyperbranched poly(urea-urethane)s with OH- and Ph- end groups were carried out to obtain a number of macromolecular samples possessing different molar masses at the same chemical structure. The characterization of the polymers was performed by SEC, MALLS, 1H-NMR, MALDI-TOF-MS and viscosity measurements. Modifications of the OH-end groups of the polymers were carried out. We observed a strong influence of the end groups on the solution behaviour of the hyperbranched samples. The molecular shape of the hyperbranched polymers in solution was compared to their linear analogue using the Kuhn-Mark-Houwink- Sakurada relationship. The calculated contraction factors between 0,15 and 0,7 depending on the molar masses correspond to a very compact structure of the modified branched polymers at high molar masses.

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