Polyvinylchloride melt rheology II?the influence of molecular weight on flow activation energy

1970 ◽  
Vol 10 (2) ◽  
pp. 57-65 ◽  
Author(s):  
E. A. Collins ◽  
A. P. Metzger
Keyword(s):  
Activation Energy ◽  
Molecular Weight ◽  
Melt Rheology ◽  
Flow Activation Energy ◽  
Flow Activation

Flow Behavior of Heterocyclic Aramid Concentrated Solution

2010 ◽  
Vol 146-147 ◽  
pp. 470-474
Author(s):  
Lei Chen ◽  
Zu Ming Hu ◽  
Bao Shan Gao ◽  
Guo Ping Tang ◽  
Jun Rong Yu ◽  
...  
Keyword(s):  
Activation Energy ◽  
Molecular Weight ◽  
Flow Behavior ◽  
Viscosity Index ◽  
Solution Concentration ◽  
Structural Viscosity ◽  
Flow Activation Energy ◽  
Flow Activation ◽  
Concentrated Solution ◽  
Newtonian Behavior

By means of HAAKE RS105L cone and plate rheometer the rheological behavior of heterocyclic aramid concentrated solution, including viscous flow activation energy, non-Newtonian index, structural viscosity index of the heterocyclic aramid solution were studied. The effect of concentration and temperature of the solution and molecular weight of the polymer on its non-Newtonian behavior was investigated. The results showed that heterocyclic aramid concentrated solution prepared via low temperature condensation was non-Newtonian fluid. With the decrease of temperature, increase of solution concentration and heterocyclic aramid molecular weight, the deviation of the solution from Newtonian behavior decreased. The molecular weight of the polymer and the concentration of the solution affected the non-Newtonian behavior more intensively.

scholarly journals Rheological Behavior and Its Chemical Interpretation of Crumb Rubber Modified Asphalt Containing Warm-Mix Additives

2018 ◽  
Vol 2672 (28) ◽  
pp. 337-348 ◽  
Author(s):  
Haopeng Wang ◽  
Xueyan Liu ◽  
Panos Apostolidis ◽  
Tom Scarpas
Keyword(s):  
Activation Energy ◽  
Molecular Weight ◽  
Rheological Properties ◽  
Phase Angle ◽  
Complex Modulus ◽  
Crumb Rubber ◽  
Asphalt Binders ◽  
Flow Activation Energy ◽  
Modified Asphalt ◽  
Flow Activation

The microstructure and chemical composition of asphalt binders have a significant effect on their rheological properties and, therefore, their performance as road paving binders. This study aims to investigate the effects of warm-mix asphalt (WMA) additives, organic type and chemical type, on the rheological properties and chemical internal structure of base asphalt and crumb rubber modified asphalt (CRMA). A set of dynamic shear rheometer (DSR) tests was conducted to obtain the rheological parameters (e.g., complex viscosity, complex modulus, phase angle) of asphalt binders. The flow activation energy was calculated from Arrhenius equation based on viscosity data to rank the thermal susceptibility. Black diagrams and master curves of complex modulus and phase angle were utilized to analyze the rheological properties. The molecular weight distributions of asphalt binders were inverted from the phase angle master curve to evaluate the molecular weight characteristics. It was found that the the addition of crumb rubber into base asphalt improves the rheological properties of enhanced modulus and elasticity. Organic and chemical types of WMA additives have different chemo-physical effects on both base asphalt and CRMA. Phase angle inversion method provides a powerful tool to monitor the molecular structure change and, therefore, the chemo-physical interactions of asphalt binders induced by modifications. Finally, there is a good correlation between flow activation energy and molecular weight.

Rheological Study on of PBT with High Melt Flow Index

2012 ◽  
Vol 487 ◽  
pp. 644-648
Author(s):  
Yuan Liu ◽  
Lin Wang ◽  
Qing Yan Xu ◽  
Pei Jie Lin ◽  
Zhi Hong Guo ◽  
...  
Keyword(s):  
Activation Energy ◽  
Shear Rate ◽  
Apparent Viscosity ◽  
Melt Flow Index ◽  
Flow Index ◽  
Melt Flow ◽  
Flow Activation Energy ◽  
Nonwoven Fabrics ◽  
Flow Activation ◽  
High Flexibility

Melt-blown generated PBT nonwoven fabrics usually have small fibril diameter, high flexibility, well heat and oil resistance. Therefore, they would have promising application such as vehicle filtering media. The rheological behavior of PBT with High Melt Flow Index for Melt-blown is investigated in this paper. It is a direction of the technology design and fabrication parameters .The relation of apparent viscosity and shear rate is analyzed, as well as flow activation energy and Non-Newtonian indexes. The results suggest that PBT with High Melt Flow Index is Non-Newtonian fluid. Apparent viscosity and flow activation energy show gradually decrease with increasing shear rate, exhibiting typical shear-thinning behavior.

Rheological Behaviors of Graphene Oxide/Polyacrylonitrile Spinning Solutions

2017 ◽  
Vol 898 ◽  
pp. 2187-2196 ◽  
Author(s):  
Feng Mei Li ◽  
Ying Ying Zheng ◽  
Biao Wang
Keyword(s):  
Activation Energy ◽  
Graphene Oxide ◽  
Loss Factor ◽  
Viscosity Index ◽  
Structural Viscosity ◽  
Mechanical Loss ◽  
Flow Activation Energy ◽  
Rheological Behaviors ◽  
Flow Activation ◽  
Mechanical Loss Factor

The rheological behaviors of polyacrylonitrile (PAN) in NaSCN aqueous solutions containing different amount of Graphene oxide (GO) were investigated through both steady-state and dynamic rheological measurements. The parameters such as apparent viscosity (ηα), flow activation energy (Eη), structural viscosity index (Δη), storage modulus (G’), loss modulus (G’’) and mechanical loss factor (tanδ) were measured to illustrate the rheological behaviors of these solutions. The results showed that the apparent viscosity decreased with adding appropriate amount of GO, while the structural viscosity index, the flow activation energy and the mechanical loss factor of GO/PAN spinning solutions increased. Accordingly, a possible mechanism of GO effect on rheological behaviors of PAN solution was proposed in this work.

Thermal Oligomerisation of Cardanol

e-Polymers ◽  
2006 ◽  
Vol 6 (1) ◽  
Author(s):  
Francisco Helder A. Rodrigues ◽  
José Roberto R. Souza ◽  
Francisco Célio F. França ◽  
Nágila M. P. S. Ricardo ◽  
Judith P. A. Feitosa
Keyword(s):  
Activation Energy ◽  
Double Bond ◽  
Average Molecular Weight ◽  
Hydrocarbon Chain ◽  
Relative Mass ◽  
Cashew Nut Shell Liquid ◽  
Flow Activation Energy ◽  
H Nmr ◽  
Cashew Nut ◽  
Flow Activation

AbstractCardanol was extracted from technical Cashew Nut Shell Liquid (CNSL), a naturally occurring meta-substituted long chain phenol and oligomerized by heating at 140 °C. Products were characterized by rheology, infrared and 1H NMR spectroscopy and thermogravimetric analysis (TGA). Increase in viscosity and the flow activation energy was found with increasing time of heating. The relative absorbance of double bond of the hydrocarbon chain decreased with time of heating and indicated that the oligomerization is taking place through the unsaturation of the side chain. Decrease in internal double bond as well as in vinyl bond, observed by 1H NMR, pointed out to the participation of these two kinds of unsaturation as well as monoene, diene and triene. The oligomerization is a slow process. With 40 h of heating, the average molecular weight increases only by 46%. Great differences were found in TGA curves of cardanol with different times of oligomerization. Thermal stability increases with time of heating. The degree of oligomerization could be determined from relative mass loss of the first event of TG, or from flow activation energy.

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