MECHANISTIC THEORY OF THE LOAD - ELONGATION PROPERTIES OF PAPER - 2. THE CHARACTERISTICS OF FIBRES TAKEN INTO ACCOUNT.

The theory of the load-elongation of paper presented at the 1965 Cambridge Symposium of the (then) British Paper and Board Makers' Association has been improved. It has developed into a mechanistic theory whose final expressions do not contain any empirical constants. The theory interrelates the elastic modulus, tensile strength, failure strain, and zero-span tensile strength of papers with both a random and a biased fiber-orientation distribution. Agreement is obtained between the theory and data for handsheets of five widely-differing pulps. The first described the approach employed in developing the theory, the basic assumptions, and the characteristics of the fibers under consideration. This second part describes the straining of a sheet up to the moment of tensile failure. The application of these concepts to the zero-span tensile test is also included.