Gutta percha deformation

Natural rubber is known to be more elastic (deformable) than gutta-percha. Is there any obvious difference in the structures in the two strands which might lead to a difference in the properties of the real polymers ... 

Gutta-percha, the trans 1,4-isomer of natural rubber, is hard and brittle at room temperature. The reason for the difference in properties between the cis and trans isomers readily can be seen by inspecting molecular models. The chains with trans double bonds are able to lie along side of each other, forming a semicrystalline array, as shown in Figure 13-2. This ordered arrangement cannot be deformed easily, hence the material is hard and brittle. However, when the double bonds are cis, steric hindrance prevents the chains from assuming a similar ordered structure and the bulk of the material exists in a... 

Deformation of frozen rubber, gutta percha and balata.631... 

It was known that caoutchouc and gutta-percha (another purified tree sap) had the same empirical formula. When gutta-percha was subjected to the same force applied to the caoutchouc, it did not deform as much, and it cooled, as expected What was so different about these two otherwise chemically identical substances Crystallinity The crystal deformed as an elastic body and the sample returned to the same temperature upon release of the force. Joule subjected caoutchouc to a cooling-bath at 0° Fahrenheit for a few days. The sample then became rigid and showed the same elasticity as the gutta-percha. Joule worked like Faraday he tried everything ... 

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