Synthesis, Structures and Properties of Organosilicon Supramolecular Elastomers Constructed by Multiple Hydrogen Bonds
|Keywords||multiple hydrogen bonds polydimethylsiloxane elastomer supramolecularself-assembly|
Supramolecular polymer constructed by hydrogen bonds, comparing with covalent-bonded polymer, has its unique advantages, environmental corresponding. Polydimethylsiloxane (PDMS) possesses many specific properties, such as resistance at both high and low temperature, antioxidation, climate resistance, low glue-temperature factor, low surface tension, hydrophobicity, and biological inertness. Organosilicon elastomer constructed by hydrogen bonds have both advantages of PDMS and hydrogen bonds, which will have theoretical significance and application value in preparation of materials with excellent properties. The preparation of organosilicon elastomers based on multiple hydrogen bonds and their modification were studied in this paper.Because2-ureido-4-H-pyrimidinone (UPy) can form dimmer for its self-assembly property, it was widely used to synthesize elastomers based on multiple hydrogen bonds. Herein, we successfully synthesize a series of block polymer with UPy as hard block and polydimethylsiloxane with different molecular weight as soft block. The elastomers obtained own outstanding mechanical properties, such as tensile strength up to2.05MPa and exhibit thermoplastic property. The influences of hydrogen bond crosslink density, aggregation state and temperature on the mechanical properties were also discussed.It is well known that crosslinking agents and reinforced materials were used to improve the mechanical properties of silicone rubber. Thus, crosslinking agents and silica were also utilized to modify the elastomer in this paper. The crosslinking density from hydrogen bonding crosslinking agent was so high that the elastomer exhibited poor mechanical properties. Meanwhile, the mechanical properties of the elastomer modified by silica increased. The optimal addition proportion of crosslinking agent and silica need to be further studied.The silicone supramolecular elastomers obtained in this work displayed wonderful mechanical properties. Utilizing silica to modify the elastomer was firstly mentioned and provided an effective method to improve mechanical properties of silicone supramolecular elastomers.