Using a model colloidal system of alumina and polyacrylic acid (PAA), the kinetics of flocculation was investigated at low polymer concentrations and short durations (on the order of seconds). The polymer-induced flocculation processes obeyed Von Smoluchowski's bimolecular rate equation. Increases in the concentration of the polymer resulted in higher rate constants for the flocculation process. At a fixed concentration (say 50 ppb, parts per billion), the rate constant values showed a maximum value for 250,000 g mol(-1) polyacrylic acid. At this polymer concentration, calculations of the surface coverage of alumina by PAA molecules of different molecular weights show that for all the cases the coverage is nearly the same, approximately 1x10(-3), but the flocculation response and the rates are significantly different. This trend in flocculation characteristics is attributed to the critical polymer number density requirement for effective flocculation (at least partial charge neutralization and initiation of flocculation). The mechanism governing the flocculation at ultralow concentrations (50 ppb) is the synergistic effect of partial patch neutralization and bridging.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.jcis.2003.11.010 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Double-Dynamic-Bond Cross-Linked Hydrogel Adhesive with Cohesion-Adhesion Enhancement for Emergency Tissue Closure and Infected Wound Healing.
Adv Healthc Mater
January 2025
College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu, 610065, China.
The hydrogel adhesives with strong tissue adhesion and biological characteristics adhm202404447are urgently needed for injury sealing and tissue repair. However, the negative correlation between tissue adhesion and the mechanical strength poses a challenge for their practical application. Herein, a bio-inspired cohesive enhancement strategy is developed to prepare the hydrogel adhesive with simultaneously enhanced mechanical strength and tissue adhesion.
View Article and Find Full Text PDFIncreasing the waterproof performance of fatliquored leather by silane modification: a simple and feasible green treatment method.
RSC Adv
January 2025
Zhejiang Province Key Lab of Leather Engineering, College of Chemistry and Materials Engineering, Wenzhou University Wenzhou 325035 Zhejiang China
Waterproof fatliquoring agents can transform leather from a hydrophilic state to a hydrophobic state in the wet process of leather production. However, traditional waterproof fatliquoring agents may cause environmental pollution. Fluorocarbons in fluorinated fatliquoring agents are difficult to degrade, and polyacrylic acid fatliquoring agents require chromium powder fixation.
View Article and Find Full Text PDFPrimary Dentin Conditioning with Methylene Blue Activated Photodynamic Therapy, Phytic Acid, and Er,Cr:YSGG to Resin-Modified Glass Ionomer Cement in Comparison to Conventional Polyacrylic Acid.
Photobiomodul Photomed Laser Surg
January 2025
Department of Preventive Dental Sciences, College of Dentistry, Dar Al Uloom University, Riyadh, Saudi Arabia.
Impact of surface conditioner phytic acid (IP6) Er,Cr:YSGG laser (ECYL) methylene blue photodynamic therapy (MB-PDT) on the microleakage and shear bond strength (SBS) of resin-modified glass ionomer cement (RMGIC) to primary sound dentin. Overall, 80 extracted sound primary molars were collected followed by their submergence in self-cure acrylic resin. The dentin surface was exposed and made flat and was assigned into four groups based on the surface conditioning.
View Article and Find Full Text PDFPhytic Acid-Induced Gradient Hydrogels for Highly Sensitive and Broad Range Pressure Sensing.
Adv Mater
January 2025
Laboratory of Advanced Theranostic Materials and Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, 315201, P. R. China.
Ionic conductive hydrogels have emerged as an excellent option for constructing dielectric layers of interfacial iontronic sensors. Among these, gradient ionic hydrogels, due to the intrinsic gradient elastic modulus, can achieve a wide range of pressure responses. However, the fabrication of gradient hydrogels with optimal mechanical and sensing properties remains a challenge.
View Article and Find Full Text PDFNanoarchitectonics of a Skin-Like Polymeric Hydrogel with High Anti-Swelling and Self-Adhesion Performance for Underwater Communication.
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 PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!