Technical Paper Archive


This site contains all papers presented at Rubber Division, ACS Technical Meetings from 2000-2018. Meetings prior to 2000 are incomplete and papers are added as they are digitized.


For older papers not listed here, please send your request, including Meeting Year, Title, Author, and Paper # to: cbrady@rubber.org


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The Characterization and Correlation of the Network Chain Density to the Properties of Fluoroelastomer Rubber

E19 pazur network chain density rct

Event: 196th Technical Meeting - Fall 2019
Location: Cleveland, OH
Date: October 08, 2019
Author: Richard Pazur
Paper Number: E19

Price: $20.00

  • Fluoroelastomer (FKM) rubbers are used in many demanding applications due to their ability to resist the attack of heat, chemicals, and solvents. Chemical crosslinking is known to have a major impact on the final product’s physical properties, thus the determination of crosslink type and quantity is extremely important for understanding material properties. In this investigation, a peroxide curable FKM terpolymer containing 67 wt% of fluorine was used. Triallyl isocyanurate (TAIC) was employed as peroxide coagent and its levels were varied from 1 to 5 phr in order to induce a crosslink density gradient. Experimental analysis was undertaken using rheometry, hardness, stress-strain (Mooney-Rivlin), equilibrium solvent swell and low field nuclear magnetic resonance (NMR) using the double quantum (DQ) technique. Increasing the concentration of TAIC coagent caused a systematic rise in rheometry torque, hardness and tensile strength while both elongation at break and swelling levels decreased. These results are concurrent with an enhanced overall level of crosslinking. This trend was confirmed by the steady increase observed by Mooney-Rivlin C1 and C1 + C2 values with increasing coagent concentration. The DQ NMR technique through use of fast Tikhonov regularization (ftikreg) was particularly useful in discerning the inhomogeneous nature of the compound morphology by detection with both the hydrogen and fluorine probes. The spatial distribution of the crosslink density suggests that the compound consists of small highly polymerized TAIC domains imbedded within the elastic crosslinked matrix. The optimal concentration of TAIC coagent was 3 phr according to compression set test results.

    Papers from 196th Technical Meeting - Fall 2019

    Items from 196th Technical Meeting - Fall 2019