Composites Reinforced by Liquid Crystalline Polymers

It has been concluded that in fiber reinforced composites the aspect ratio L/D of the fiber is one of the most important parameters in controlling the uniaxial modulus and ultimate tensile strength (Kardos and Raisoni, 1975). 

Source Liquid Crystalline Polymers edited by National Materials Advisory Board, Washington, DC, 1990. 

The composite systems studied by Takayanagi et al. (1980) used the polyaramides poly(p-phenylene terephthamide), PPDT, or pol.y-p-benzamide (PBA) as the reinforcing component with nylon 6 or nylon 66 as the ductile matrix polymer. Block copolymers of one of the aromatic polyamides with one of the nylon polymers were also evaluated. The blends were prepared by extruding the sulfuric acid solutions of polymers into a 

Sample Mol. Wt. of PPTA PPTA/Nylon Young s modulus Yield stress Ultimate strength Elongation at break 

Oriented (d rawn at 170 °C to three times its original length)  

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