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<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" xml:lang="en" id="abs0010" view="all" class="author"><ce:section-title id="sectitle0010">Abstract</ce:section-title...
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<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" xml:lang="en" id="abs0010" view="all" class="author"><ce:section-title id="sectitle0010">Abstract</ce:section-title><ce:abstract-sec id="abssec0010" view="all"><ce:simple-para id="abspara0010" view="all">In a foregoing article, a new method based on dynamic mechanical thermal analysis(DMTA)for determining the degrees of crystallinity of the natural rubber (NR) and the eucommia ulmoides (<ce:italic>EU</ce:italic>) gum, with different crosslink densities, has been established. In order to verify the effectiveness of this method, in the present paper, the degrees of crystallinity of NR and<ce:italic>EU</ce:italic>gum with different crosslink densities will be determined by differential scanning calorimetry (DSC). The results indicate that the degrees of crystallinity determined by DMTA are much higher than those of DSC. This is because the degree of crystallinity determined by DMTA involves not only the ratio of the crystalline zone, but also the ratio of the mesomorphic zone, while the degree of crystallinity tested by DSC includes only the ratio of the crystalline zone. So, the degree of crystallinity, the degree of mesomorphic zone and the degree of amorphous zone of NR and<ce:italic>EU</ce:italic>gums with different crosslink densities can be quantitatively determined by the combination of DMTA and DSC. The results show that the degree of crystallinity, the degree of mesomorphic zone and the degree of amorphous zone of NR (crystallized at??25?°C for 12?h) and<ce:italic>EU</ce:italic>gum are 33%, 53%, 14% and 34%, 54%, 13%, respectively. For NR, increasing the crosslink density or decreasing the induced time will decrease the degree of crystallinity and the degree of mesomorphic zone simultaneously, but will increase the degree of amorphous zones. For<ce:italic>EU</ce:italic>gum, increasing the crosslink density will decrease the degree of crystallinity and increase the degree of amorphous zone, but keep the degree of mesomorphic zone invariably consistent within the critical crystallization point, which is approximately 55%. At the end of the paper, the impact of crystallization on the mechanical properties of<ce:italic>EU</ce:italic>gum and NR is discussed as well.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" class="graphical" id="abs0015" view="all"><ce:section-title id="sectitle0015">Graphical abstract</ce:section-title><ce:abstract-sec id="abssec0015" view="all"><ce:simple-para id="abspara0015" view="all">The number of free chain segments of the amorphous zone in NR and<ce:italic>EU</ce:italic>gum, tested through DMTA, can be used to calculate their degree of crystallinity, which involves not only the ratio of the crystalline zone, but also the ratio of the mesomorphic zone. So, the degree of crystallinity determined by DMTA is much larger than that of DSC. As a result, the degree of crystallinity, the degree of mesomorphic zone and the degree of amorphous zone of NR and EU gums can be quantitatively determined by DMTA and DSC, which are 33%, 53%, 14% and 34%, 54%, 13%, respectively.</ce:simple-para><ce:simple-para>Display Omitted</ce:simple-para></ce:abstract-sec></ce:abstract>]]>
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