Abstract

The effects of polyacrylic acid (PAA) on the hierarchical structure of sheepskin collagen fibres were investigated by using of transmission electron microscope (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). It was found that although the unique axial periodic (d periodicity) structure of collagen fibrils and orderly arrangement of collagen molecule did not change obviously after the introduction of PAA, the aggregation behaviour of collagen fibres was greatly influenced.With increasing concentration of PAA, the order of intermolecular lateral packing decreased, the shrinkage of the leather lessened [from changes in surface morphology observed by SEM] and the dry heat stability of collagen fibre declined due to a decrease in the orderly degree of collagen fibre aggregation.