© Department of Materials Science and Technology, IIT Delhi
Amino Acid-Derived Alternating Polyampholytes
Prof. Priyadarsi De
Department of Chemical Sciences, Indian Institute of Science
Education and Research Kolkata, India
Abstract
Polyampholytes are polymers containing both cationic and anionic repeating units. Among the different types of polyampholytes, polyzwitterions (such as sulfo-, carboxy-, and phospho- betaines) bearing both cationic and anionic groups together in the same monomer unit are mostly studied in the literature. In addition to the zwitterionic polymers, the development of charge-neutral polyampholytes based on cationic and anionic monomers are extremely challenging as stoichiometric amounts of both the monomers are to be incorporated.
The general strategy for the synthesis of polyampholytes is copolymerization of different unsaturated monomers carrying a positive or negative charge functionality either in a protected or deprotected form. The feed ratio, as well as relative reactivity of the co-monomers, dictate the net charge of the polyampholyte. The inherently different reactivity of co-monomers will result in the compositional drift as well as haphazard placement of the charge units throughout the polymer chain. Thus, it is highly attractive to develop an effective synthetic strategy for polyampholytes without any compositional drift, as the solution performances (e.g., solubility, isoelectric point (IEP)) of polyampholytes are closely related to the composition. In the present lecture, combining the above concerns we outlined a new approach for the synthesis of a novel leucine-derived strictly alternating cationic and anionic moiety based polyampholyte with 1:1 charge balance.
To this end, we have engineered an alternating polyampholyte based on poly(styrene-alt-maleimide) skeleton by judicious copolymerization of N-maleoyl-L-leucine tert-butyl ester (M1) with tert-butyl carbamate (Boc)-protected leucine appended styrenic monomer (M2) via reversible addition-fragmentation chain transfer (RAFT) polymerization. Since electron donating styrenic monomers undergo copolymerization with an electron accepting N- substituted maleimide monomers in an alternating fashion,1-8 we were able to achieve polymer chains having a cationic and anionic functional moiety in a regular alternating fashion i.e. a charge-neutral polyampholyte on the elimination of the protecting groups.
Keywords: next-gen batteries; inexpensive-safe-improved energy storage; multifaceted materials challenges; solid-state electrochemistry
Abstract
Polyampholytes are polymers containing both cationic and anionic repeating units. Among the different types of polyampholytes, polyzwitterions (such as sulfo-, carboxy-, and phospho- betaines) bearing both cationic and anionic groups together in the same monomer unit are mostly studied in the literature. In addition to the zwitterionic polymers, the development of charge-neutral polyampholytes based on cationic and anionic monomers are extremely challenging as stoichiometric amounts of both the monomers are to be incorporated.
The general strategy for the synthesis of polyampholytes is copolymerization of different unsaturated monomers carrying a positive or negative charge functionality either in a protected or deprotected form. The feed ratio, as well as relative reactivity of the co-monomers, dictate the net charge of the polyampholyte. The inherently different reactivity of co-monomers will result in the compositional drift as well as haphazard placement of the charge units throughout the polymer chain. Thus, it is highly attractive to develop an effective synthetic strategy for polyampholytes without any compositional drift, as the solution performances (e.g., solubility, isoelectric point (IEP)) of polyampholytes are closely related to the composition. In the present lecture, combining the above concerns we outlined a new approach for the synthesis of a novel leucine-derived strictly alternating cationic and anionic moiety based polyampholyte with 1:1 charge balance.
To this end, we have engineered an alternating polyampholyte based on poly(styrene-alt-maleimide) skeleton by judicious copolymerization of N-maleoyl-L-leucine tert-butyl ester (M1) with tert-butyl carbamate (Boc)-protected leucine appended styrenic monomer (M2) via reversible addition-fragmentation chain transfer (RAFT) polymerization. Since electron donating styrenic monomers undergo copolymerization with an electron accepting N- substituted maleimide monomers in an alternating fashion,1-8 we were able to achieve polymer chains having a cationic and anionic functional moiety in a regular alternating fashion i.e. a charge-neutral polyampholyte on the elimination of the protecting groups.
Keywords: next-gen batteries; inexpensive-safe-improved energy storage; multifaceted materials challenges; solid-state electrochemistry
Abstract
Polyampholytes are polymers containing both cationic and anionic repeating units. Among the different types of polyampholytes, polyzwitterions (such as sulfo-, carboxy-, and phospho- betaines) bearing both cationic and anionic groups together in the same monomer unit are mostly studied in the literature. In addition to the zwitterionic polymers, the development of charge-neutral polyampholytes based on cationic and anionic monomers are extremely challenging as stoichiometric amounts of both the monomers are to be incorporated.
The general strategy for the synthesis of polyampholytes is copolymerization of different unsaturated monomers carrying a positive or negative charge functionality either in a protected or deprotected form. The feed ratio, as well as relative reactivity of the co-monomers, dictate the net charge of the polyampholyte. The inherently different reactivity of co-monomers will result in the compositional drift as well as haphazard placement of the charge units throughout the polymer chain. Thus, it is highly attractive to develop an effective synthetic strategy for polyampholytes without any compositional drift, as the solution performances (e.g., solubility, isoelectric point (IEP)) of polyampholytes are closely related to the composition. In the present lecture, combining the above concerns we outlined a new approach for the synthesis of a novel leucine-derived strictly alternating cationic and anionic moiety based polyampholyte with 1:1 charge balance.
To this end, we have engineered an alternating polyampholyte based on poly(styrene-alt-maleimide) skeleton by judicious copolymerization of N-maleoyl-L-leucine tert-butyl ester (M1) with tert-butyl carbamate (Boc)-protected leucine appended styrenic monomer (M2) via reversible addition-fragmentation chain transfer (RAFT) polymerization. Since electron donating styrenic monomers undergo copolymerization with an electron accepting N- substituted maleimide monomers in an alternating fashion,1-8 we were able to achieve polymer chains having a cationic and anionic functional moiety in a regular alternating fashion i.e. a charge-neutral polyampholyte on the elimination of the protecting groups.
Keywords: next-gen batteries; inexpensive-safe-improved energy storage; multifaceted materials challenges; solid-state electrochemistry
© Department of Materials Science and Engineering, IIT Delhi