Experimental Data on Fiber-Reinforced TPS

In reality, not all fibers will break exactly in the middle. If a fracture in the matrix material encounters the fiber close to one end, pull-out will always occur. If a failure in the matrix material reaches the fiber in the middle region the fiber will break in this middle part, but if it reaches the fiber close to the tip, pull-out will occur if the distance to the tip is in the range smaller than the puU-out length. The total reinforcement of a fiber can now be determined by addition of the contributions of the three regions. 

When tests on the strength and bonding of fiber-reinforced composites need to be performed, firstly test bars have to be prepared. The total process consists of two steps. In the first step, starch is gelatinized and mixed with glycerol in an extruder and pelleted. For the experiments with fiber reinforcement the flax or cellulose fibers have to be mixed into the starch during the first process step. The pellets are then very similar to the pellets used in plastic processing and they can 

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