Abstract

The rule for the changes and mechanism influencing the structure of leather during drying were studied from the point of view of fibre movement, based on the stress state and combination mode of collagen fibres. The effect of capillary pressure difference force (CPDF) and hydrogen bonds on the aggregation behaviour of leatherʼs collagen fibres during drying was investigated. The results showed that, during hang drying, under the action of CPDF, collagen fibres will move towards each other and bond by hydrogen bonds thus making the structure of dried leather stable. During freeze drying, the collagen fibres are not affected by CPDF and the fibres tend to maintain the original dispersed state. During hang drying, when the hydrogen bond force between collagen fibres is weakened by fatliquoring, the aggregate structure of collagen fibres is unstable, and collagen fibres can be easily re-dispersed by milling. The results of this research confirmed that, during drying, the change in the collagen fibresʼ aggregate structure is due to the process inwhich collagen fibres move and combine under the action of ʻforceʼ. The final dried leather structure is determined by the stress state and combining ways of collagen fibres during drying