Robert Franz Schmidt, Jana Lutzki, Robert Dalgliesh, Sylvain Prévost, Michael Gradzielski
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引用次数: 0
Abstract
This study investigates the rheological and structural properties of interpolymer complexes (IPCs) formed between poly(ethylene oxide) (PEO) and poly(methacrylic acid) (PMAA) at various pH levels and polymer ratios. Potentiometric titration showed that PMAA must remain over 90% protonated for IPC formation. Extensive rheological experiments revealed a sharp transition from viscous to elastic behavior between pH 5.75 and 4.75. The rheological response is attributed to PEO chain entanglements and PEO–PMAA hydrogen-bond cross-links, with cross-links dominating at low pH and weakening as pH increases. Small-angle neutron scattering (SANS) highlights the structural changes, with dense, PMAA-rich domains forming at low pH and breaking down at higher pH. This work provides valuable new insights for the design of hydrogels, whose properties are easily tuned by the polymer mixing ratio and pH, offering potential for various pharmaceutical applications.
期刊介绍：
Macromolecules publishes original, fundamental, and impactful research on all aspects of polymer science. Topics of interest include synthesis (e.g., controlled polymerizations, polymerization catalysis, post polymerization modification, new monomer structures and polymer architectures, and polymerization mechanisms/kinetics analysis); phase behavior, thermodynamics, dynamic, and ordering/disordering phenomena (e.g., self-assembly, gelation, crystallization, solution/melt/solid-state characteristics); structure and properties (e.g., mechanical and rheological properties, surface/interfacial characteristics, electronic and transport properties); new state of the art characterization (e.g., spectroscopy, scattering, microscopy, rheology), simulation (e.g., Monte Carlo, molecular dynamics, multi-scale/coarse-grained modeling), and theoretical methods. Renewable/sustainable polymers, polymer networks, responsive polymers, electro-, magneto- and opto-active macromolecules, inorganic polymers, charge-transporting polymers (ion-containing, semiconducting, and conducting), nanostructured polymers, and polymer composites are also of interest. Typical papers published in Macromolecules showcase important and innovative concepts, experimental methods/observations, and theoretical/computational approaches that demonstrate a fundamental advance in the understanding of polymers.
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