Performance of slash pine fibers in fiber cement products

Cellulosic fibers produced by the kraft pulping process from slash pine trees (Pinuselliottii), a softwood from the south-eastern US, have been evaluated in fiber cement products. These fibers are longer and coarser than most wood fibers and have been found to provide many benefits in fiber cement applications due to their high modulus and high fiber strength. Lignin levels can be finely controlled ranging from 0% to 4%. Laboratory preparations of multiple formulations of fiber cement products have been carried out incorporating these fibers. High modulus of rupture, high fracture energy (toughness), excellent dimensional stability, and low water absorption were observed. Accelerated aging tests were also run and high performance mix designs showed the most strength retention after aging. Recently conducted plant trials with these fibers have confirmed laboratory findings.