Agradecimentos: The authors would like to thank the Vipal Borrachas S.A. Company and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (PROSUC funding) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) for their technical and financial support. Marco Aurelio De Paoli acknowledges a senior researcher fellowship from CNPq (Process Nr. 301933/2015-4) Ver menos

Abstract: In this study we evaluated the use of eucalyptus lignin as a stabilizer in combination with other stabilizers in a vulcanized elastomeric based on natural rubber. The stabilizers tested were 6PPD (N-1,3-dimethyl-butyl-N'-phenyl-p-phenylenediamine), TMQ (oligomerized 2,2,4-trimethylquinoline), paraffin wax and eucalyptus lignin. At predetermined time intervals, samples were taken from aging conditions and the mechanical properties and additive content were determined. The sample with a combination of wax and lignin in the same formulation showed the greatest resistance to oxidative degradation. In samples with only one stabilizer, the migration test indicated greater diffusion of lignin to the surface. Samples exposed to thermo-oxidative aging showed greater loss in the mechanical properties of tear strength and 6PPD consumption. In the accelerated aging with ozone, all showed a behavior more resistant to aging. We concluded that lignin can be used as a substitute for synthetic stabilizers, without impairing the performance of natural rubber compounds Ver menos