Moisture and Durability

The major chemical constituents of natural fibers contain hydroxyl and other oxygen containing groups that attract moisture through hydrogen bonding [16]. The 

Fiber/fiber bundles Density (g/cm ) Stiffness (GPa) Strength (MPa) Elongation at break %) References 

Fiber 30% Relative humidity 65% Relative humidity 90% Relative humidity 

Due to their low thermal stability, natural fibers are generally processed with plastics where high temperatures are not required (less than about 200 °C). Above these temperatures, many of the polymeric constituents in natural fibers begin to decompose. Since cellulose is more thermally stable than other chemical constituents, highly pulped fibers that are nearly all cellulose have been used to extend this processing window ]11, 17]. 

The release of volatile gases can, before, during, and after processing, lead to odor issues in applications where the composite is in an enclosed environment such as in many automotive applications and especially when moisture is present [18]. 

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