FTP, name this strong synthetic fiber used in sails, kayaks, firefighter gloves, run-flat tires, and bullet-proof vests.
It is a polyamide in which all the amide groups attach to the phenyl rings opposite to each other at carbons 1 and 4, forcing it to maintain a "trans" formation, producing long, stackable fibers.  Its high tensile strength, flame resistance, high chemical resistance, and high cut resistance made its inventors, Herbert Blades and Stephanie Kwolek of DuPont, unsure of what it could be used for, as it could not easily be melted down or put in solution. FTP, name this strong synthetic fiber used in sails, kayaks, firefighter gloves, run-flat tires, and bullet-proof vests.
It is a polyamide in which all the amide groups attach to the phenyl rings opposite to each other at carbons 1 and 4, forcing it to maintain a "trans" formation, producing long, stackable fibers.  
Kevlar