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High Refractive Index, Enantiopure Silicones Based on BINOL
Miguel Melendez-Zamudio1, Kaitlyn E C Silverthorne1, Michael A Brook1
1Department of Chemistry and Chemical Biology, McMaster University, 1280 Main St., W., Hamilton, ON, L8S 4M1, Canada.
Macromolecular Rapid Communications
|February 26, 2022
Summary
High refractive index (RI) silicone polymers were developed using binaphthol (BINOL). Chain extension of BINOL macromers yielded polymers with RI up to 1.58, demonstrating BINOL
Area of Science:
- Polymer Chemistry
- Materials Science
- Organic Chemistry
Background:
- High refractive index (RI) materials are crucial for advanced optical applications.
- Aromatic compounds like binaphthol (BINOL) offer potential for increasing polymer RI.
- Silicone polymers are versatile but often have moderate RI.
Purpose of the Study:
- To investigate the incorporation of binaphthol (BINOL) into silicone polymer chains to enhance refractive index.
- To develop methods for synthesizing high RI silicone-based materials.
- To explore the use of BINOL in creating novel copolymers and elastomers.
Main Methods:
- Utilizing the Piers-Rubinsztajn (PR) reaction for BINOL incorporation into silicone polymers.
- Chain extension of short vinyl-capped BINOL macromers with arylsilanes via hydrosilylation.
- Synthesis of alternating and random linear copolymers, and elastomers.
Main Results:
- Successfully synthesized BINOL-rich silicone polymers with high refractive indices.
- Achieved polymers with molar masses up to 8000 and RI up to 1.58 through chain extension.
- Demonstrated the facile preparation of BINOL-containing elastomers.
Conclusions:
- Binaphthol (BINOL) can be effectively incorporated into silicone polymers to significantly augment refractive index.
- Chain extension via hydrosilylation is a viable method for producing high RI linear silicone polymers from short BINOL macromers.
- The facile synthesis suggests broad applicability of BINOL in developing advanced optical materials.
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