FIBRE FOR THE FUTURE: WHEAT STRAW THE RING CRUSH STRENGTH AND CREEP OF WHEAT STRAW AND EUCALYPT PULP HANDSHEETS

摘要

This paper investigates ring crush strength and creep properties of wheat straw pulp handsheets and compares them with those of hardwood pulps. At their natural fines level, chemical pulp from wheat straw had higher ring crush strength compared to straw high yield pulp and eucalypt NSSC pulp fibres but, at similar fines level, eucalypt was a better fibre. In comparison to the effect of pulping process, the effect of fibre properties was more profound on the ring crush strength but creep seamed to be affecting more with pulping conditions, rather than the fibre properties; the high yield straw pulp crept faster compared to that of straw chemical pulp. The effect of fines on both ring crush strength and creep was also quite significant. Higher fines content in straw pulp is a positive attribute of straw fibre that could reduce the higher costs involved in conventional refining of hardwoods and softwoods. This study suggested that wheat straw has a good potential to be used in substitution to eucalypt fibres if the pulping conditions are optimized similar to those of straw chemical pulp. High yield pulp from wheat straw is not suitable as it has poor resistance to creep. This study also confirmed that ring crush strength has a poor relationship with creep and can mislead in determining the end performance of a product.