Terminally and randomly functionalized polyisoprene lead to distinct aggregation behaviors of polar groups

Non-covalent interactions imposed by polar groups affect the properties of polyisoprene in various ways. But traditional modification method only led to randomly functionalized product which ignored the effects of sequence and location of polar groups. In this work, by using a novel polar monomer hydroxyl-myrcene (HMY), hydroxyl group terminally (BC–OH) and randomly functionalized (RC-OH) polyisoprene copolymers were successfully obtained. Due to the different hydroxyl group sequences, BC-OH and RC-OH shows different morphologies and rheological properties. Furthermore, polyhedral oligomeric silsesquioxanes (POSS) with urea bond was used as nanofiller to attach on BC-OH and RC-OH and generating BC-POSS and RC-POSS, respectively. The assembly of POSS and the formation of urea hydrogen bond will occur collaboratively. As a result, BC-POSS and RC-POSS showed distinct morphological properties and thermal stabilities . It is found that ordered urea bonds were formed in RC-POSS, while less ordered urea bonds were formed in BC-POSS. Overall, these results suggest that the tailoring of polar group sequence in polyisoprene copolymers could be a promising avenue for tuning polyisoprene performance via tuning aggregation behaviors of the polar groups.