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Starlike Branched Polyacrylamides by RAFT Polymerization-Part I: Synthesis and Characterization
Benjamin Klemm1, Francesco Picchioni1,2, Frank van Mastrigt1,2
1Department of Chemical Engineering, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands.
ACS Omega
|January 8, 2019
Summary
This study synthesized starlike branched polyacrylamides (SB-PAMs) with controlled molecular weights up to 1250 kDa. Researchers systematically varied monomer ratios to achieve precise control over polymer architecture and properties.
Area of Science:
- Polymer Chemistry
- Materials Science
- Macromolecular Engineering
Background:
- Controlled polymerization techniques are crucial for designing polymers with specific architectures and properties.
- Starlike branched polymers offer unique rheological and solution behaviors compared to linear counterparts.
- Reversible Addition-Fragmentation chain Transfer (RAFT) polymerization provides excellent control over polymer molecular weight and architecture.
Purpose of the Study:
- To synthesize starlike branched polyacrylamides (SB-PAMs) using RAFT copolymerization and chain extension.
- To investigate the effect of monomer ratios ([BisAM]/[AM]) on the synthesis of macromolecular chain transfer agents (macro-CTAs).
- To achieve high molecular weight SB-PAMs with tunable properties through controlled chain extension.
Main Methods:
- Synthesis of SB-PAMs via RAFT copolymerization of acrylamide (AM) and N,N'-methylenebis(acrylamide) (BisAM) using a specific chain transfer agent.
- Systematic variation of the [BisAM]/[AM] ratio in the core structure (0.010–0.143).
- Chain extension of the synthesized core structures with AM to produce high molecular weight polymers.
Main Results:
- Successfully synthesized macromolecular chain transfer agents with molecular weights ranging from 2.2–7.8 kDa and polydispersity indices of 1.2–15.1.
- Demonstrated controlled polymerization kinetics, indicating effective control over the polymerization process.
- Prepared high molecular weight SB-PAMs with apparent molecular weights spanning from 19 to 1250 kDa.
Conclusions:
- The study successfully demonstrated the synthesis of starlike branched polyacrylamides with precisely controlled molecular weights.
- Systematic variation of monomer ratios allows for fine-tuning of polymer architecture and properties.
- The developed method provides a viable route for producing high molecular weight branched polymers for various applications.
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