STRUCTURAL-ANALYSIS OF COLLAGEN-FIBERS BY NITROGEN ADSORPTION METHOD

Nitrogen adsorption and desorption isotherms on untreated collagen fiber and collagen fibers treated for 10, 20, and 30 days with calcium hydroxide were investigated. Surface area of the untreated collagen fiber was 2.2 m2/g. Pore size distributions of the collagen fibers were calculated by the micropore method and the Dollimore-Heal method from the adsorption isotherms to elucidate the relationship between alkali treatment period and porosity. The differential micropore volumes, with radii of 15.5 to 24.5 Å, and the cumulative pore volumes, with radii larger than 12 Å, of the collagen fibers treated for 20 days were the largest. The result was well explained by the results of the C constant calculated from the BET equation. © 1993 by Academic Press, Inc.