Monoaxial stretched PP-films are used for the manufacture of hot-compacted layered composites. These are layered with stretched co-extruded coupling agent films, and are consolidated to laminates by means of a hot-compaction process, which employs pressure and temperature. This paper aims to examine the influence of the process settings on the properties of the composites during the hot-compaction process. For this purpose, the mechanical values will be determined by means of tensile testing variously compacted and configured layered film composites. 1. Introduction and Fundamentals In regards of their morphological properties, self-reinforced composite materials display an exceptionally good mechanical property profile [1]. The incorporation of a self-reinforcement leads to a high orientation of the molecule chains, enabling a utilization of the high covalent bonding forces for reinforcement [2]. This orientation of the molecules induces an anisotropy which makes a manifold increase of the mechanical properties, that is, stiffness and strength [3], possible in comparison to injection molded basic material [4]. Due to the fact that the matrix and reinforcement fibers of self-reinforced composite systems are made of an identical basic material [5, 6], recycling these material systems is very simple [1]. Moreover, self-reinforced composite systems have a high lightweight potential because of their low density ( = 0.91？g/cm3). In contrast to conventionally fiber-reinforced components, such as polymer systems with a relatively heavy glass fiber reinforcement ( = 2.5？g/cm3), low component wall strengths can be achieved at a low composite density owing to the high property level [1]. The basis for the creation of self-reinforcement is founded upon two basic principles. First, it is based upon the macromolecular orientations which are incorporated in the polymer. Second, it depends upon the generation of directed crystalline structures [7]. The deliberately induced deformation of the polymer in both the melt and solid phases enables a transfer of the two principles, however, with varying effects on the morphology. The stretch and shear flows in the melt liquid phase cause an orientation of the macromolecules in the direction of the flow [8]. For example, stretch flows occur due to tapering the flow channel in form of a nozzle (Figure 1). The flow velocity of the melt increases as a result of a reduction of the nozzle cross section, leading to an alignment of the molecule chains in flow direction. If suitable thermic and rheological conditions are on hand, the
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