Hypothesis: The rheological behavior and frictional properties (macroscopic level) of systems containing a hydrophobically modified polymer and phospholipids depend on the hydrophobic association that occur between the hydrophobic moiety of the polymer and the phospholipid tails (molecular level). The hydrophobicity of the polymer can thus be used to control its interactions with phospholipids, and manipulate complex gel macroscopic behavior.
Experiments: By using systems composed of a crosslinked hydrophobically modified polyacrylic acid (HMPAA) or a crosslinked polyacrylic acid polymer (PAA) and phospholipids, we examine the underlying mechanisms through which the components interact using isothermal titration calorimetry (ITC) and their effect on rheological and tribological characteristics of complex gels.
Findings: We find the systems containing HMPAA and phospholipid exhibit gel-like behavior with the elastic modulus increasing substantially upon phospholipid addition due to hydrophobic interactions that result in a more interconnected network formation, as evidenced by ITC measurements. Similar experiments with a crosslinked polyacrylic acid polymer (PAA) show no interactions, lending credence to our hypothesis. In addition, soft tribological behavior shows lower friction coefficients at low entrainment speeds with HMPAA concentration and the addition of phospholipid, while no change in friction coefficient was observed in the case of increasing PAA concentration, indicating HMPAA and phospholipids to be interacting with the soft PDMS contacts.
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http://dx.doi.org/10.1016/j.jcis.2020.09.113 | DOI Listing |
Macromol Rapid Commun
January 2025
Qingdao Innovation and Development Center, Harbin Engineering University, Qingdao, 266000, China.
Hydrogels are flexible materials characterized by a 3D network structure, which possess high water content and adjustable physicochemical properties. They have found widespread applications in tissue engineering, electronic skin, drug delivery, flexible sensors, and photothermal therapy. However, hydrogel networks often exhibit swelling behavior in aqueous environments, which can result in structural degradation and a loss of gel performance.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
Chemistry Department, Lomonosov Moscow State University, Moscow 119991, Russia.
Polymer-based aqueous redox flow batteries (RFBs) are attracting increasing attention as a promising next-generation energy storage technology due to their potential for low cost and environmental friendliness. The search for new redox-active organic compounds for incorporation into polymer materials is ongoing, with anolyte-type compounds in high demand. In response to this need, we have synthesized and tested a range of new water-soluble redox-active s-tetrazine derivatives, including both low molecular weight compounds and polymers with different architectures.
View Article and Find Full Text PDFCarbohydr Polym
March 2025
State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, 15 North Third Ring Road East, Chaoyang District, Beijing 100029, China. Electronic address:
Conductive hydrogels have emerged as excellent candidates for the design and construction of flexible wearable sensors and have attracted great attention in the field of wearable sensors. However, there are still serious challenges to integrating high stretchability, self-healing, self-adhesion, excellent sensing properties, and good biocompatibility into hydrogel wearable devices through easy and green strategies. In this paper, multifunctional conductive hydrogels (PCGB) with good biocompatibility, high tensile (1694 % strain), self-adhesive, and self-healing properties were fabricated by incorporating boric acid (BA) and glucose (Glu) simultaneously into polyacrylic acid (PAA) and chitosan (CS) polymer networks using a simple one-pot polymerization method.
View Article and Find Full Text PDFBMC Oral Health
January 2025
Faculty of Dentistry, Basic Medical Sciences Department, Ankara University, Ankara, 06560, Turkey.
Background: This study aimed to comparatively evaluate the effects of different cavity conditioners on internal adaptation (IA) of glass ionomer-based restorative materials applied to primary teeth.
Methods: 80 extracted primary second molar teeth were randomly assigned to four different cavity conditioner groups [10% polyacrylic acid, 20% polyacrylic acid, 17% ethylene diamine tetraacetic acid (EDTA), 35% phosphoric acid]. Class V cavities were prepared on the buccal surfaces and relevant cavity conditioners were applied, and the samples in each cavity conditioner group were randomly assigned to glass hybrid (GHR) or conventional glass ionomer restoratives (CGIR).
Polymers (Basel)
December 2024
Department of Chemistry, University of Hannam, Daejeon 34430, Republic of Korea.
The chemical mechanical polishing/planarization (CMP) is essential for achieving the desired surface quality and planarity required for subsequent layers and processing steps. However, the aggregation of slurry particles caused by abrasive materials can lead to scratches, defects, increased surface roughness, degradation the quality and durability of the finished surface after milling processes during the CMP process. In this study, ceria slurry was prepared using polymer dispersant with zinc salt of ethylene acrylic acid (EAA) copolymer at different contents of 5, 6, and 7 wt% (denoted as D5, D6, and D7) to minimize particle aggregation commonly observed in CMP slurries.
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