AbstractNovalac resin (N) with hexamethylenetetramine (HTA) was cured with biomass (B) or Kraft lignin (KL) or hydroxymethylated Kraft lignin (KLH) or cellulose (CEL). The agricultural/industrial by‐product of olive stones was used as biomass. Kraft lignin, hydroxymethylated Kraft lignin and cellulose were isolated from the biomass. The cure was followed by DSC and IR spectroscopy. Based on the IR spectra of cured materials and their characteristic bands, the proportion of N/B = 50/50 was chosen for the preparation of novolac mixtures with other components. Only N–KLH exhibited values of ΔH higher than ΔHm, calculated from the law of mixtures, indicating that KLH participates in the cure reaction. The kinetic parameters E and K0 of the total cure reactions, calculated by DSC scans, increased in the order N < N–KLH < N–B < N–KL < N–CEL. The incorporation of KLH in the mass of N–HTA led to a slight increase in E and k0. On the other hand, KL, CEL and B acted as diluents in the mass of novolac. Generally, the cure of all materials was a first order reaction, indicating that the cure mechanism of novolac remains the same.