Table I.

Mechanical Properties of Silk and High-performance Synthetic Fibers^a

Fiber Type	Density (g/cm3)	Modulus of Elasticity (GPa)	Tensile Strength (GPa)	Breaking Strain (%)	Resilience (MJ/m3)
Spider dragline silk
Argiope trifasciata	1.3	1 – 10	1.2	30	100
N. clavipes	1.3	1 – 10	1.8	30	130
Silkworm silk	1.3	5	0.6	12	50
Nylon 6,6	1.1	5	0.9	18	80
Kevlar 49	1.4	130	3.6	3	50
PBOb	1.6	270	5.8	3	70
Steel	7.8	200	3	2	6

^aModified from reference 36.

^bPolybenzoxazole