Location: Plant Polymer ResearchTitle: Birchwood biochar as partial carbon black replacement in styrene-butadiene rubber composites Author
|Peterson, Steven - Steve|
Submitted to: Journal of Elastomers and Plastics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/29/2014
Publication Date: 6/1/2016
Publication URL: http://handle.nal.usda.gov/10113/5510073
Citation: Peterson, S.C., Chandrasekaran, S.R., Sharma, B.K. 2016. Birchwood biochar as partial carbon black replacement in styrene-butadiene rubber composites. Journal of Elastomers and Plastics. 48(4):305-316. Interpretive Summary: One motivation of the tire industry is to reduce their dependence on fossil fuels and byproducts produced from fossil fuels. The tire industry wants to do this for three reasons, 1) fossil fuel products have traditionally gone up in price over time, due to increasing global demand, 2) there is always the threat that eventually this finite resource will run out completely, and 3) using renewable resources in their products increases their popularity with customers as an ecologically responsible company. Carbon black is one of these fossil fuel byproducts that the tire industry has used extensively for over 50 years. Carbon black is a filler material; by adding it to rubber it makes tires stronger, more durable, and easier to manufacture. Biochar is a form of charcoal that has high carbon content similar to carbon black, but it is made from renewable resources such as trees. In this study, we use a biochar made from birchwood and combine it with carbon black to make blended fillers at various ratios. By demonstrating that rubber composites made with blended biochar and carbon black have equal or better material properties than those made with just carbon black, that means that carbon black usage can be reduced without any loss in the final composite properties. This work shows that 25-50% carbon black can be replaced with birchwood biochar with no detrimental effects to the final product.
Technical Abstract: Birchwood feedstock was used to make slow pyrolysis biochar that contained 89% carbon and < 2% ash. This biochar was blended with carbon black as filler for styrene-butadiene rubber. Composites made from blended fillers of 25/75 biochar/carbon black were equivalent to or superior to their 100% carbon black analogs in terms of tensile strength and toughness at all filler concentrations. Composites made with 50/50 biochar/carbon black were equivalent to or superior to carbon black composites in tensile strength, elongation, and toughness properties at total filler concentrations up to 30%. These results demonstrate the potential to use renewable birchwood biochar to replace up to half the carbon black in certain styrene-butadiene rubber composites.