Test Method for High-Shear Viscosity Using a Cone/Plate Viscometer

The objective of this study is determining the mixing and compaction temperature of the modified asphalt mixture. Results of binder tests showed that the addition of 3% SBS to control asphalt (PG 64-16) would achieve the desired performance level (PG 76-16) a performance grade that fits our climate with traffic loads. When using 5% SBS the performance grade of binder increased three grades (PG 82-16) and when increasing SBS content to 8% the performance grade increased four grades (PG 88-16). At shear rate of 500 (s-1), the modified asphalt viscosity can be obtained at different temperatures and the viscosity temperature curve can be achieved. As a result, the mixing and compaction temperature of modified asphalt can be determined to reach 0.17 ± 0.02 Pa.s and 0.28 ± 0.03 Pa.s for mixing and compaction, respectively. It is noted that SBS modified reached a viscosity of 3 Pa.s when 8 % additive. Additive contents above these values may not be suitable for good workability and pump ability according to Superpave specifications. While addition of 5% SBS with control asphalt, more than 3.7times at 135°C Increase the viscosity. Marshall Stability test indicated that the strength for the SBS specimens increases as compared to the conventional specimens. An increase of about 39%, 74%, 102%, was observed with 3%SBS 5%SBS 8%SBS modified binders, respectively. The Marshall test results for 8%SBS binders required compaction temperatures above 175°C need to keep up quality of HMA item while limiting natural effect amid development, these proposals are unsatisfactory Modified mixtures the 5% SBS modification was determined to be the maximum useful content. The Superpave method to estimate mixing and compaction temperatures show are not practical for use with modified binders. Also, it is observed that good agreement values between the average Marshall compaction temperature and the High Shear Viscosity Method (HSRV) and lower than Superpave methods Where the decline ranges from 15 ºC to 17 ºC.

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Paper X(iii) High-shear viscosity studies of polymer-containing lubricants

Tribology Series - Fluid Film Lubrication – Osborne Reynolds Centenary, Proceedings of the 13th Leeds–Lyon Symposium on Tribology, held in Bodington Hall, The University of Leeds ◽

10.1016/s0167-8922(08)70960-x ◽

1987 ◽

pp. 325-332 ◽

Cited By ~ 7

Author(s):

J.L. Duda ◽

E.E. Klaus ◽

S.C. Lin ◽

F.L. Lee

Keyword(s):

Shear Viscosity ◽

High Shear

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On the 3D Printability of Multi-Walled Carbon Nanotube/High Density Polyethylene Composites

Volume 2: Processes; Materials ◽

10.1115/msec2019-2776 ◽

2019 ◽

Author(s):

Felicia Stan ◽

Nicoleta-Violeta Stanciu ◽

Catalin Fetecau

Keyword(s):

Carbon Nanotube ◽

Electrical Properties ◽

3D Printing ◽

Shear Viscosity ◽

High Density Polyethylene ◽

High Density ◽

High Shear ◽

Shear Rates ◽

Mechanical And Electrical Properties ◽

Multi Walled Carbon Nanotube

Abstract This study focuses on 3D printing of multi-walled carbon nanotube/high density polyethylene (MWCNT/HDPE) composites. First, rheological properties of 0.1, 1, and 5 wt.% MWCNT/HDPE composites were investigated to estimate the 3D printability window. Second, filaments with 1.75 mm diameter were fabricated and subsequently extruded by a commercial 3D printer. Finally, the filaments and 3D printed parts were tested to correlate the rheological, mechanical, and electrical properties with processing parameters. Experimental results show that flow behavior of MWCNT/HDPE composites is a critical factor affecting the 3D printability. The shear viscosity exhibits good shear thinning behavior at high shear rates and significantly increases with increasing nanotube loading from 0.1 to 5 wt.%, at low shear rates. Reliable MWCNT/HDPE filaments were obtained with smooth surface finish and good mechanical and electrical properties. The 0.1 and 1 wt.% MWCNT/HDPE filaments exhibit very good printing characteristics. However, under the flow conditions of a standard 0.4-mm nozzle, 3D printing of 5 wt.% MWCNT/HDPE filament can be rather difficult primarily due to high shear viscosity and nozzle clogging. Thus, further investigation is needed to fully optimize the 3D printing of MWCNT/HDPE composites.

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