Iron ion cluster-OH coordination as high-efficiency sacrificial bond for reinforcement of elastomer

• Published in: Polymer (Guilford) 2020-01, Vol.186, p.122059, Article 122059
• Main Authors: Zhang, Xuhui, Huang, Jing, Tang, Zhenghai, Guo, Baochun, Zhang, Liqun
• Format: Article
• Language: English
• Subjects: Clusters; Coordination; Crosslinking; Elastomer; Elastomers; Hydroxy-ion cluster coordination; Industrial applications; Iron; Metal ions; Polymers; Reinforcement; Rubber; Tensile strength
• ISSN: 0032-3861; 1873-2291
• DOI: 10.1016/j.polymer.2019.122059

Although hydroxy is an easily-available group for polymer functionalization and can serve as a ligand to coordinate with metal ions, the hydroxy-ion cluster coordination remains unexploited as sacrificial bond to reinforce elastomers. This work reports a very strong rubber by introducing iron ion cluster-OH coordination into a covalently-crosslinked rubber. With the introduction of 4.2 wt% Fe3+, the rubber exhibits a 6-fold increase in tensile strength and an 8-fold increase in modulus when compared with neat rubber. The achieved tensile strength (~20.9 MPa) and modulus (~12.7 MPa) are competitive to the highly-filled engineering rubbers. Overall, this work presents a new method to prepare high performance elastomers based on a hydroxylated polymer. As hydroxylated polymers can be readily prepared with commercially available polymers, the present study should promote comprehensive research and industrial applications of sacrificial bond strategy. By introducing reversible iron ion cluster-OH bonds into a covalently crosslinked rubber as sacrificial bonds, a very strong elastomer with a 6-fold increase in tensile strength and 8-fold increase in modulus is achieved. As hydroxylated polymers can be prepared readily with commercially available polymers, the present study should promote comprehensive research and industrial applications of sacrificial bond strategy. [Display omitted] •Iron ion cluster-OH coordination between hydroxylated rubber and Fe3+ is verified.•Iron ion cluster-OH coordination is highly efficient in rubber reinforcement in a sacrificial manner.•The achieved tensile strength is comparable to highly-filled engineering rubbers.