PHYSICOELECTRICAL PROPERTIES AND PIEZORESISTIVE SENSING OF THE EXTRUSION-BASED CONDUCTIVE RUBBER COMPOSITES: SIMULTANEOUS EFFECTS OF THE EXTRUSION PARAMETERS

2020 ◽  
pp. 000-000
Author(s):  
Jirawat Narongthong ◽  
Pongdhorn Sae-Oui ◽  
Manuchet Nillawong ◽  
Chakrit Sirisinha
Keyword(s):  
Mechanical Strength ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Rubber Composites ◽  
Screw Speed ◽  
Soft Matrix ◽  
Screw Design ◽  
Conductive Rubber ◽  
Twin Screw ◽  
Styrene Butadiene

ABSTRACT Flexible conductive rubber composites (CRCs) were prepared based on carbon black–filled oil-extended styrene–butadiene rubber soft matrix. Using a variety of screw designs, the simultaneous effects of the twin-screw extrusion parameters (i.e., kneading element, dispersing position, and screw speed) on the physicoelectrical properties of the CRCs were investigated statistically. The increased intenseness of the extrusion parameters significantly enhances the piezoresistive sensing via the improved filler dispersion, increased rubber–filler interaction, and weakened filler–filler networks. Nevertheless, the influence of the kneading elements on the properties of the CRCs significantly decreases with an increase in the intenseness of the dispersing position or the screw speed, referred to as a “negative interaction.” An extreme intenseness of the screw design causes the excellent piezoresistive sensing of the CRCs, but with undesirable mechanical strength. Because those properties need to be balanced, many methods of adjusting the CRCs to be more suitable for strain-sensor application, in terms of not only piezoresistive performance but also mechanical strength, were thus established.

TIME AND TEMPERATURE DEPENDENT PIEZORESISTIVE BEHAVIOR OF CONDUCTIVE ELASTOMERIC COMPOSITES

2018 ◽  
Vol 91 (4) ◽  
pp. 651-667 ◽  
Author(s):  
Eshwaran Subramani Bhagavatheswaran ◽  
Klaus Werner Stöckelhuber ◽  
Sankar Raman Vaikuntam ◽  
Sven Wießner ◽  
Petra Pötschke ◽  
...  
Keyword(s):  
Electrical Resistance ◽  
Specific Effect ◽  
Temporal Changes ◽  
Rubber Matrix ◽  
Styrene Butadiene Rubber ◽  
Physical Parameters ◽  
Butadiene Rubber ◽  
Rubber Composites ◽  
Conductive Rubber ◽  
Styrene Butadiene

ABSTRACT We report about systematic studies on dynamic piezoresistive characteristics of conductive rubber composites. The temporal changes in electrical resistance of flexible electrically conductive rubber composites were simultaneously monitored during dynamic mechanical loading. Thus, influences of physical parameters such as frequency, temperature, strain amplitude, and matrix stiffness were explored in detail, and the mechanisms behind qualitatively discussed. The filler clusters were found to rearrange in the elastomer matrix during dynamic deformation, witnessed by the decrease in electrical resistance over time. Each test parameter had its own specific effect on the piezoresistance response, and the findings offered an understanding on the filler networking inside the solution styrene butadiene rubber matrix from the perspective of the dynamic piezoresistive characteristics. Higher piezoresistive response was observed near the glass transition temperature. We offer a deeper insight into the behavior and temporal changes in corresponding filler clusters during dynamic deformations of conducting rubber systems.

scholarly journals Best Practice for De-Vulcanization of Waste Passenger Car Tire Rubber Granulate Using 2-2′-dibenzamidodiphenyldisulfide as De-Vulcanization Agent in a Twin-Screw Extruder

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1139
Author(s):  
Hans van Hoek ◽  
Jacques Noordermeer ◽  
Geert Heideman ◽  
Anke Blume ◽  
Wilma Dierkes
Keyword(s):  
Best Practice ◽  
Chain Scission ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Twin Screw Extruder ◽  
Screw Extruder ◽  
Passenger Car ◽  
Tire Rubber ◽  
Twin Screw ◽  
Styrene Butadiene

De-vulcanization of rubber has been shown to be a viable process to reuse this valuable material. The purpose of the de-vulcanization is to release the crosslinked nature of the highly elastic tire rubber granulate. For present day passenger car tires containing the synthetic rubbers Styrene-Butadiene Rubber (SBR) and Butadiene Rubber (BR) and a high amount of silica as reinforcing filler, producing high quality devulcanizate is a major challenge. In previous research a thermo-chemical mechanical approach was developed, using a twin-screw extruder and diphenyldisulfide (DPDS) as de-vulcanization agent.The screw configuration was designed for low shear in order to protect the polymers from chain scission, or uncontrolled spontaneuous recombination which is the largest problem involved in de-vulcanization of passenger car tire rubber. Because of disadvantages of DPDS for commercial use, 2-2′-dibenzamidodiphenyldisulfide (DBD) was used in the present study. Due to its high melting point of 140 °C the twin-screw extruder process needed to be redesigned. Subsequent milling of the devulcanizate at 60 °C with a narrow gap-width between the mill rolls greatly improved the quality of the devulcanizate in terms of coherence and tensile properties after renewed vulcanization. As the composition of passenger car tire granulate is very complex, the usefulness of the Horikx-Verbruggen analysis as optimization parameter for the de-vulcanization process was limited. Instead, stress-strain properties of re-vulcanized de-vulcanizates were used. The capacity of the twin-screw extruder was limited by the required residence time, implying a low screw speed. A best tensile strength of 8 MPa at a strain at break of 160% of the unblended renewed vulcanizate was found under optimal conditions.

Preparation and characterization of lignin-layered double hydroxide/styrene-butadiene rubber composites

2013 ◽  
Vol 130 (2) ◽  
pp. 1308-1312 ◽  
Author(s):  
Suo Xiao ◽  
Jianxiang Feng ◽  
Jin Zhu ◽  
Xi Wang ◽  
Chunwang Yi ◽  
...  
Keyword(s):  
Layered Double Hydroxide ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Rubber Composites ◽  
Double Hydroxide ◽  
Styrene Butadiene

Using heat-treated starch to modify the surface of biochar and improve the tensile properties of biochar-filled styrene–butadiene rubber composites

2018 ◽  
Vol 51 (1) ◽  
pp. 26-35
Author(s):  
Steven C Peterson ◽  
Sanghoon Kim
Keyword(s):  
Tensile Properties ◽  
Styrene Butadiene Rubber ◽  
Filler Materials ◽  
Butadiene Rubber ◽  
Rubber Composites ◽  
Heat Treated ◽  
Matrix Interactions ◽  
Renewable Material ◽  
Styrene Butadiene ◽  
Properties Of Composites

Heat-treated starch (HTS) is a renewable material that can be used to modify the surface chemistry of small particles. In this work, HTS was used to coat hydrophilic biochar particles in order to make them more hydrophobic. Then, when added as filler to hydrophobic styrene–butadiene rubber (SBR), the coated biochar dispersed more easily and had enhanced filler–matrix interactions, which were reflected in the tensile properties of the final composites. Biochar particles modified with 5% (weight) HTS showed increases of 59% in the ultimate tensile strength, 49% in elongation percentage, and 79% in fracture toughness of SBR composites compared to unmodified biochar particles. This shows that HTS can be used to improve the tensile properties of composites filled with biochar and potentially other hydrophilic filler materials.

Sign in / Sign up

Export Citation Format

Share Document