Cellulose fiber‐polyester composites with reduced water sensitivity (1)—chemical treatment and mechanical properties

Formaldehyde and di‐methylomelamine were used to modify the surfaces of cellulose fibers. Composites were prepared with unsaturated polyester and treated cellulose as the reinforcing material. The tensile strength and the elongation of the cellulose fibers were determined in dry and wet conditions as well as the tensile strength and the tensile modulus of the cellulose‐polyester composites. The water uptake of the composites was reduced by 46 to 52 percent. The wet strength of the composites was improved by more than 50 percent.