Solubilizing Benzodifuranone-Based Conjugated Copolymers with Single-Oxygen-Containing Branched Side Chains

Area of Science:

• Materials Science
• Polymer Chemistry
• Organic Electronics

Background:

• Developing soluble n-type organic semiconductors is crucial for advancing organic electronics.
• Benzodifuranone (BDF)-thiophene copolymers show promise but often suffer from poor solubility.
• Controlling side chain architecture is key to tuning polymer properties.

Purpose of the Study:

• To design and synthesize novel single-oxygen-containing branched side chains.
• To improve the solubility of BDF-isatin-thiophene based n-type copolymers.
• To investigate the impact of side chain design on copolymer properties and performance.

Main Methods:

• A modular and straightforward synthetic approach using commercially available reagents.
• Design of side chains with varying linker distances between the polymer backbone and branching point.
• Characterization of copolymer solubility, molar mass, optoelectronic, and thermoelectric properties.

Main Results:

• Achieved excellent solubilities for BDF-thiophene copolymers up to 90 mg/mL.
• Synthesized moderately sized side chains (26-34 atoms).
• Demonstrated that electrical conductivity scales with molar mass, reaching ~1 S/cm.

Conclusions:

• Single-oxygen-containing branched side chains effectively solubilize n-type BDF-thiophene copolymers.
• Enhanced solubility allows for high molar mass polymers with improved electrical conductivity.
• The synthetic strategy offers a versatile route for tuning polymer properties for organic electronics.