Colloidal and deposition behavior of Pinus radiata extractives and model colloid systems

Colloidal and deposition behaviour of wood extractives from Pinus radiata was studied and compared to reported behaviour of Picea abies. Differences in composition between the two species can be used to explain the differences in behaviour with P.radiata extractives being less stable against electrolyte induced aggregation with calcium and having a stronger interaction with fibre surfaces. Model studies undertaken to investigate the effect of triglycerides on the colloid have lead to modifications to the wood extractive droplet model which better explain the pitch deposition behaviour in paper mills using P.radiata to manufacture mechanical paper grades.