In the quest to make polymer production more sustainable, researchers have turned to water as a solvent, but the challenge of copolymerizing hydrophobic and hydrophilic monomers in aqueous media has persisted. A recent study published in Nano Select, which translates to “Nano Choice,” offers a promising solution using cyclodextrins (CDs) to facilitate this process. The research, led by Alexy Sanseigne from the Département de Chimie at Université de Montréal in Canada, demonstrates a novel approach that could have significant implications for industries, including the energy sector.
The study focuses on the copolymerization of a hydrophobic acrylamide derivative of cholic acid (CAAM) with acrylamide in water. “The key innovation here is the use of cyclodextrins to form inclusion complexes with the hydrophobic monomers, making them soluble in water,” Sanseigne explains. This technique allows for the copolymerization to occur in a common and environmentally benign solvent, water.
The researchers found that β-cyclodextrin (β-CD) was particularly effective in solubilizing CAAM in water. However, an excess of β-CD was required to achieve effective solubilization, leading to the synthesis of a thermoresponsive polymer. Interestingly, the final copolymer contained approximately 2.5 mol% of CAAM, which is half of the 5 mol% present in the initial feed. This discrepancy highlights the importance of the stability of the inclusion complex in the copolymerization process.
The study also explored the use of γ-cyclodextrin (γ-CD), which has a larger cavity than β-CD. The results showed that γ-CD formed a looser inclusion complex with CAAM, resulting in a copolymer with only 0.74 mol% of CAAM. “This indicates that the stability of the complexation plays a crucial role in the efficiency of the copolymerization process,” Sanseigne notes.
The implications of this research are far-reaching, particularly for the energy sector. The development of thermoresponsive polymers that can be synthesized in water offers a more sustainable and cost-effective approach to polymer production. These polymers could be used in various applications, such as enhanced oil recovery, where their thermoresponsive properties could improve the efficiency of oil extraction.
Moreover, the use of cyclodextrins to solubilize hydrophobic monomers in water opens up new possibilities for the design and synthesis of complex polymers. “This technique could be applied to a wide range of hydrophobic monomers, expanding the toolkit for polymer chemists and enabling the development of new materials with unique properties,” Sanseigne suggests.
In conclusion, the research published in Nano Select represents a significant advancement in the field of aqueous polymerizations. By leveraging the power of cyclodextrins, researchers have developed a more sustainable and efficient method for copolymerizing hydrophobic and hydrophilic monomers. This innovation could pave the way for the development of new materials with applications in the energy sector and beyond, contributing to a more sustainable future.