Ribbon Reinforced Composites

Ribbon reinforced composites are widely used in prosthetics, particularly in the field of orthodontics where canine-to-canine retention is carried out with the help of resin composite retainers reinforced with kevlar /polyethylene ribbons. These composites can have high strength and stiffness in two directions: longitudinal and in-plane direction. Such composites can nearly be isotropic in the plane of a sheet exhibiting almost equal strength in all directions [refer Figure 24.1].

Figure 24.1: Cross section of a typical ribbon reinforced composite

The aligned fiber composites have poor transverse strength and may be replaced by ribbon reinforced composites as per requirements. They are less prone to crack and require less care in handling. They are also fairly resistant to puncture by sharp objects. Additional advantage of ribbon as reinforcement is that they can be packed in larger volume fractions in comparison to circular fibers.