Black Reinforcement of Rubbers"
No.6 : Strain-Induced Crystallization and Self-Reinforcement of NR
(1)What has been made clear concerning the phenomenon?
Polymer Engineering Design
Nippon Gomu Kyokaishi,(2004),77(11),397-403 General Review in Japanese
Natural rubber has a great
tensile property, the very high tensile strength in particular, without
the addition of carbon blacks, which has been understood to result
from the stain-induced crystallization. However, there has been much
discussion and confusion about the sudden stress increase at a large
extension, i.e." the upturn" in NR.That is, one explains the phenomenon
from the viewpoint of the reinforcement of rubber by crystals (but
without any detailed discussion) and the other depicts with the non-Gaussian
stress-strain relation, ignoring the strain-induced crystallization.
Here, we focus on the strain-induced crystallization and the cross-linked
structures of NR and search the hints to link the strain-induced crystallization
to the self-reinforcement in NR.
Natural rubber, Strain-induced crystallization, The upturn, Cross-linked