Functionalized Rigid Ladder Polymers from Catalytic Arene-Norbornene Annulation Polymerization

Area of Science:

• Polymer Chemistry
• Materials Science

Background:

• Rigid ladder polymers offer unique properties but face challenges in synthesis and diversity.
• Existing synthetic methods limit the structural variety and functionalization of these polymers.

Purpose of the Study:

• To synthesize novel rigid ladder polymers with diverse functional groups.
• To explore copolymerization and postpolymerization functionalization strategies for ladder polymers.
• To investigate the properties and potential applications of these functionalized polymers.

Main Methods:

• Catalytic arene-norbornene annulation (CANAL) polymerization was employed.
• Functional groups were incorporated via copolymerization of functionalized monomers or postpolymerization modification.
• Characterization of polymer structure, solubility, and porosity was performed.

Main Results:

• Successfully synthesized ladder polymers with kinked norbornyl benzocyclobutene backbones.
• Incorporated a wide range of functional groups including alcohols, amines, esters, and heterocycles.
• Demonstrated that functionalization modifies polymer properties like solubility and compatibility.
• Maintained microporous and highly glassy characteristics.

Conclusions:

• Catalytic arene-norbornene annulation provides a versatile route to functionalized rigid ladder polymers.
• Functionalization significantly expands the utility of these polymers for various applications.
• The resulting polymers are suitable for separation and high-temperature applications due to their inherent properties.