Green compounds of SBR with nanofibrilated cellulose and palm oil in replacement to traditionally compounds used

Abstract

Silica and carbon black (CB) are the most used reinforcement fillers in elastomeric compositions; however, their obtention and usage might result in environmental and human health damages. The same happens to the plasticizers used in elastomeric compounds, which contain a high content of polycyclic aromatics. To use reinforcement and plasticizer loads from natural sources, the performance of an elastomeric compound by partially replacing CB with nanofibrillated cellulose (CEL) provided with Eucalyptus spp. shavings was evaluated in this work, as well as, the use of palm oil to replace aromatic oils. Nanofibrilated cellulose was obtained by grinding in a micronizing mill. As a characterization of the raw material, the thermal, chemical and morphological properties, as well as particle size analysis of the cellulose suspension were evaluated by the particle size analyzer. From the vulcanized material, the physical, mechanical, dynamic-mechanical properties, cross-link density, and swelling index in solvents were evaluated. As the main results obtained, the presence of CEL clusters seen by scanning electron microscopy with nanofibers with diameters of 100–85 nm was observed. The dynamic light scattering particle size analyzers (DLS) showed nanoparticles from 1 to 100 nm. The rheometric properties showed lower values for the parameters of safety time, optimal vulcanization time, and maximum and minimum torques when compared to samples with CEL as CB. For tear resistance properties, samples with the presence of nanofibrilated cellulose showed 48% more resistance than samples with CB, in the modulus of elasticity, cross-link density, and swelling index, a better performance was also achieved for the samples with CEL, along with presenting a similar behavior in the hardness property between samples with the presence of nanofibrillates and those with CB. Palm oil, a substitute for aromatic oil, was found to be similar in the evaluated properties results, with interaction with CEL, by chemical affinity, which can replace aromatic oil.