Effect of masterbatch drying methods on the properties of rubber reinforced with renewable hydrophilic filler

Authors: Jong, Lei

Submitted to: Journal of Elastomers and Plastics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/17/2021
Publication Date: 5/12/2021
Citation: Jong, L. 2021. Effect of masterbatch drying methods on the properties of rubber reinforced with renewable hydrophilic filler. Journal of Elastomers and Plastics. 54(1):3-21. https://doi.org/10.1177/00952443211017179.
DOI: https://doi.org/10.1177/00952443211017179

Interpretive Summary: Natural rubber reinforced with natural fillers such as nano-cellulose and nano-protein have improved useful mechanical properties. We have investigated the effect of processing methods used to incorporate these hydrophilic fillers into natural rubber. In this study, the effect of processing methods on the mechanical properties of these natural rubber composites are renewable and sustainable, and a wide variety of applications such as damping supports, machine belts, seals, hoses, gaskets, etc. can be developed. The results of the present study will facilitate the development of economical processing methods to create a new rubber filler market for soybean growers and processing industries.

Technical Abstract: Hydrophilic fillers contain functional groups capable of forming hydrogen and/or ionic bonds. Many recent developments with biobased fillers are masterbatch processed with rubber latex. The effect of inhomogeneity in the process influences the characteristics of filler network and therefore rubber properties. In this study, the reinforced rubber is investigated using crosslink density, dynamic mechanical properties, stress softening effect, stress relaxation, tensile properties, and thermal degradation. Stress softening effect is analyzed with the Kraus model and shows that the characteristic strains shifted to smaller strains for the rubbers prepared by an inhomogeneous process. Stress relaxation of the reinforced rubber prepared from the two different processes shows that the inhomogeneous rubbers have slower relaxation rates because of higher crosslink density and modulus. Overall, the rubber composites prepared under inhomogeneous state have higher crosslink density, greater softening effect, slower rate of stress relaxation, and higher moduli attributed to greater interactions between hydrophilic components in the reinforced rubber.