maybe following article is help to you

s10973-007-8854-5.pdf https://link.springer.com/content/pdf/10.1007/s10973-007-8854-5.pdf

Thank you Chen Ding

The following article maybe helpful:

https://dergipark.org.tr/tr/download/article-file/313971

Thank you Debarati Ghosh

Hello, the endothermic peak at room temeprature is probably due to melting of the crystalline regions. EPDM is a copolymer containing ethylene sections that can crystallize: depending on the lenght of the ethylene sections, large or small crystallites can form. The size of crystallites affects the melting temperature, which can fall in the room temperature region. Concerning the exothermic peak, it is likely due to cold crystallization of the amourphous polyethylene regions. Upon heating, amorphous sections can gain enough thermal energy to rearrange in a crystalline form, and the relevant energy exchange is the reason for your peak.

Post a spectrum for better evaluation!