793
Relating papermaking process parameters to properties of paperboard with special attention…
Fig. 2 Tensile strength as func- tion degree of anisotropy for the whole paperboard and the free-laid plies
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1.000 1.100 1.200 1.300 1.400 1.500 1.600 1.700 1.800 1.900 2.000 Board MD Board CD TP MD TP CD MP MD MP CD BP MD BP CD Degree of anisotropy, A
0.00
Fig. 3 Strength of free-laid plies as function of density
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MP BP TP
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Density [kg/m 3 ]
Fig. 4 The geometrical mean in MD and CD elastic modulus normalized with fiber length show a liner relation with density
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MP BP TP
0.0 500.0
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Density [kg/m 3 ]
used to make fair approximations about the fiber orientation effect on the plies. The density of the paperboard plies as well as the fiber length will affect the strength properties. If the strength σ 0
was plotted versus density one can see that the strengths of the three plies became grouped into different clusters. The difference could be explained by the difference in fiber length of the fibers used in the different plies. Here, we
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