Hierarchal Structure and Mechanical Properties of Natural Rubber

Hierarchal Structure of natural rubber was analyzed in terms of NMR measurement and transmission electron microscopy. Nanomatrix of non-rubber components such as proteins and phospholipids was found to be inherently formed in natural rubber, in which natural rubber particles of about 1 um in average diameter were dispersed. The nanomatrix of non-rubber components disappeared after deproteinization of natural rubber with urea. Stress at break of natural rubber did not change after deproteinization, while strain at break increased. The stress at break became significantly dependent upon the amount of non-rubber components. Viscoelastic properties of natural rubber were significantly dependent upon the nanomatrix of non-rubber components.