CROSS-LINKING OF DERMAL SHEEP COLLAGEN USING HEXAMETHYLENE DIISOCYANATE

The use of hexamethylene diisocyanate (HMDIC) as a crosslinking agent for dermal sheep collagen (DSC) was studied. Because HMDIC is on ly sl ightly water soluble, a surfactant was used to obtain a clear and mice llar crosslinking solution and to promote the penetration of HMDIC in the DSC matrix. Using optimized conditions treatment of non-crosslinke d DSC (N-DSC) with HMDIC (H-DSC) increased the shrinkage temperature ( T-s) of N-DSC from 56 degrees C to 74 degrees C for H-DSC. A linear re lation between the decrease in free amine group content and the increa se in T-s was observed. Crosslinking with HMDIC did not influence the tensile strength of the N-DSC samples but increased the elongation at break from 141% to 163% and decreased the high-strain modulus from 26 MPa to 16 MPa for the H-DSC samples, respectively.