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Varying the composition of monomers and [[cross-link]]ing can add or change the functionality of a polymer that can alter the results obtained from DMA. An example of such changes can be seen by blending ethylene-propylene-diene monomer (EPDM) with [[styrene-butadiene rubber]] (SBR) and different cross-linking or curing systems. Nair ''et al.'' abbreviate blends as E<sub>0</sub>S, E<sub>20</sub>S, etc., where E<sub>0</sub>S equals the weight percent of EPDM in the blend and S denotes sulfur as the curing agent.<ref name="Nair">{{cite journal|last=Nair|first=T.M.|author2=Kumaran, M.G. |author3=Unnikrishnan, G. |author4= Pillai, V.B. |year=2009|title=Dynamic Mechanical Analysis of Ethylene-Propylene-Diene Monomer Rubber and Styrene-Butadiene Rubber Blends|journal=Journal of Applied Polymer Science|volume=112|pages=72–81|doi = 10.1002/app.29367}}</ref>
Increasing the amount of SBR in the blend decreased the storage modulus due to [[intermolecular]] and [[Intramolecular force|intramolecular]] interactions that can alter the physical state of the polymer. Within the glassy region, EPDM shows the highest storage modulus due to stronger intermolecular interactions (SBR has more [[steric]] hindrance that makes it less crystalline). In the rubbery region, SBR shows the highest storage modulus resulting from its ability to resist intermolecular slippage.<ref name="Nair" />
When compared to sulfur, the higher storage modulus occurred for blends cured with dicumyl peroxide(DCP)because of the relative strengths of C-C and C-S bonds.
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