Abstract

An aldehyde-acid copolymer/MMT nano-composite [P(MAA-AL)/MMT nano-composite] was prepared via monomer in-situ polymerization. Then the nano-composite was applied in a leather tanning process and the leather structure was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The reaction mechanism between P(MAA-AL)/MMT nano-composite and collagen fibres was investigated. P(MAA-AL)/MMT nano-composite has excellent dispersing properties for collagen fibres.

The tanning mechanism of P(MAA-AL)/MMT nano-composite is that, the carboxyl groups of nanocomposite are combined with the amino groups of collagen side chains by electrovalent bonds and the aldehyde groups of nano-composite are linked with the amino groups of collagen side chains by covalent bonds.

The reactivities of the active groups of polymer can be improved by incorporating nano-particles. The tanning function of P(MAA-AL)/MMT nano-composite is the combined result of nano-particles and polymer. In the combined tanning process of P(MAA-AL)/MMT nano-composite with a chrome tanning agent, the P(MAA-AL)/MMT nano-composite is firstly united with collagen as above. Then the carboxyl groups of the P(MAA-AL)/MMT nano-composite enter the chrome complex and coordinate with chrome. A crosslinking network is formed between P(MAA-AL)/MMT nanocomposite, chrome tanning agent and collagen fibres.