Libro

Descripción

Cellulose is a linear, stereoregular, and semi-crystalline polysaccharide. Linear chains of cellulose connected by hydrogen bonds form the supramolecular structure of this biopolymer, consisting of elementary nanofibrils and their bundles, called microfibrils. Each nanofibril contains ordered nanocrystallites and poorly ordered nanosized non-crystalline domains. Currently, it is clear that the two main structural models, “fringed fibrils” and “fringed micelles”, cannot explain many properties of cellulose and its derivatives. Therefore, a new structural model was proposed, which includes amorphous-mesomorphic non-crystalline domains and imperfect crystallites with paracrystalline layers on their surface. In this model, the crystallites and non-crystalline domains are located along the fibril and their alternation has a random character.