Cancarb Technical Bulletin Examines Tensile Strength Distribution in NBR

Cancarb Limited has published a Tensile Strength Distribution Technical Bulletin that shows how formulating nitrile butadiene rubber (NBR) with Thermax® N990 improves dispersion quality and supports potential cost reductions. The study compared nine materials, including two Thermax® medium thermal carbon black materials, and used tensile strength distribution instead of optical instruments to evaluate dispersion quality. NBR with Thermax® N990 is used in automotive and other applications.

Tensile Strength Distribution vs. Optical Measurement Tools

Cancarb is the leading developer of medium thermal carbon blacks and manufacturers its Thermax® products in Medicine Hat, Alberta, Canada. Ed Norton, the company’s Technical Service Manager, prepared the Tensile Strength Distribution Technical Bulletin because typical optical dispersion measurement tools may not be effective in measuring the dispersion of fillers in NBR. The study replaced furnace grade carbon blacks with Thermax® N990, a medium thermal carbon black with low modulus.

Thermax® N990 vs. Thermax® N550

As the Technical Bulletin explains, an independent testing laboratory replaced Thermax® N990 with Thermax® N550 at a ratio of 2:2:1 to maintain a compound hardness of 70 Shore A. The independent laboratory performed 36 tensile tests and determined that the compound without Thermax® N990 had the widest tensile strength distribution, an indicator of poor dispersion.

Automated Tensile Testing

With the advent of automated tensile testing equipment, it is easier to perform tensile tests and evaluate the tensile strength distributions of compounds. This information can be a helpful tool for compounders who are developing new formulations or investigating quality issues. This new Technical Bulletin from Cancarb also includes test results such as Mooney viscosity and stress at 50% and 300% strain.

Additional Information

To receive this Technical Bulletin in PDF format, visit this page on Cancarb’s website, choose the Request Access button, and complete the online form.

RDAbbott represents Cancarb products in the United States and Canada and is the exclusive distributor for Thermax® brand medium thermal carbon black in Mexico. For more information about these functional fillers, contact RDAbbott today.