Physical and chemical properties of cellulose acetate butyrate

Cellulose acetate butyrate is used to make plastic substrates with high transparency and good weather resistance, films and leveling agents and film-forming substances for various coatings. In addition to hydroxyl and acetyl groups, the molecule of CAB also contains butyryl groups, and its performance is related to the content of the three groups. The melting point and tensile strength increased with the increase of acetyl group content, and the compatibility with plasticizer and the flexibility of the film increased with the decrease of acetyl group content within a certain range. The increased hydroxyl content promotes its solubility in polar solvents. The increase of butyryl content reduces the density and enlarges the dissolution range. Contains 12% to 15% of acetyl and 26% to 29% of butyryl. Transparent or opaque pellets, tough, good weather resistance and cold resistance. Melting temperature 140 ℃. The density is 1.15～1.22g/cm3. The tensile strength is 14-52MPa, the flexural modulus is 621-2070MPa, the notched impact strength of the cantilever beam is 53-580J/m, and the Rockwell hardness is R31-116. Heat deformation temperature 45 ~ 94 ℃.