Cellulose Microfibril Angle as a Determinant of Paper Strength and Hygroexpansivity in <i>Pinus Taeda</i> L.


  • Charles E. Courchene
  • Gary F. Peter
  • John Litvay


Elastic modulus, hygroexpansivity, kraft pulp, loblolly pine, microfibril angle, paper properties, stiffness, tensile strength, wood fiber, wood properties, zero span tensile strength


To determine the importance of cellulose microfibril angle (MFA) for paper sheet mechanical properties, we prepared unbleached kraft pulps from ten individual, 10-year-old Pinus taeda (loblolly pine) trees similar in wood density, coarseness, cell-wall thickness, and fiber length but differing in MFA. MFA correlated (R2 = 0.81) linearly with zero span tensile strength of dry sheets. MFA was shown to be a major determinant of handsheet tensile strength, stretch, modulus of elasticity, stiffness, and hygroexpansivity in unrefined and refined pulps at a probability level of ≥97%. These results strongly suggest that breeding for southern pine trees with decreased MFA in the juvenile wood is highly desirable for paper mechanical products.


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