A5089108911- Advanced Sensor and Energy Harvesting Materials
- Surfactants and Colloidal Systems
- Surface Modification and Superhydrophobicity
- Polymer Surface Interaction Studies
- Water Treatment and Disinfection
- Membrane Separation Technologies
- Advanced Polymer Synthesis and Characterization
- Thermal properties of materials
- Advanced Cellulose Research Studies
- Graphene research and applications
- Lignin and Wood Chemistry
- Proteins in Food Systems
- Nanocomposite Films for Food Packaging
- Adhesion, Friction, and Surface Interactions
- Polymer composites and self-healing
- Recycling and Waste Management Techniques
- Water Systems and Optimization
- Urban Stormwater Management Solutions
- Microplastics and Plastic Pollution
- Geotechnical Engineering and Underground Structures
- Pickering emulsions and particle stabilization
- Flame retardant materials and properties
- Infrastructure Maintenance and Monitoring
- Block Copolymer Self-Assembly
- biodegradable polymer synthesis and properties
Purdue University West Lafayette
2016-2025
National Institute of Standards and Technology
2010-2022
National Institute of Standards
2012-2022
Colorado School of Mines
2022
University of Delaware
2010
Thin films of 3-aminopropyltriethoxysilane (APTES) are commonly used to promote adhesion between silica substrates and organic or metallic materials with applications ranging from advanced composites biomolecular lab-on-a-chip. Unfortunately, there is confusion as which reaction conditions will result in consistently aminated surfaces. A wide range conflicting experimental methods researchers often assuming the creation smooth self-assembled monolayers. film morphologies based on deposition...
The wetting character of surfactant based polymer brushes is examined. unique ability for the brush surfaces to be both hydrophilic and oleophobic rendered self-cleaning materials.
Abstract Due to their high surface energy, hydrophilic surfaces are susceptible contaminations which difficult remove and often ruin the surface. Traditional anti‐fog coatings especially limited by contaminants, as prevention of fogging is enhanced hydrophilicity increases. Thus, advanced solutions required incorporate some degree self‐cleaning ability without significant losses in character. Potential next generation characterized with particular emphasis on extended lifetime...
Cellulose nanomaterials are promising materials for the polymer industry due to their abundance and renewability. In packaging applications, these may impart enhanced gas barrier performance high crystallinity polarity. this work, low superior pristine nanocellulose films were produced using a shear-coating technique obtain range of anisotropic films. Induction anisotropy in film can control overall free volume system which effectively controls diffusion path; hence, controlled results...
CO2 and O2 gas permeability are paramount concerns in food packaging. Here, the of cellulose nanocrystals (CNCs) polyvinyl alcohol (PVA) coatings was explored as it relates to varied CNC content. Specifically, this work focuses on role PVA rheology barrier performance films. Results show that shear-casted films transparent have a high-order parameter, which is attributed shear-thinning behavior CNCs. The improved because synergistic effect having both alignment CNCs lower free volume....
Abstract Nanocomposites of cross‐linked methacrylate polymers with silver nanoparticles have been synthesized by coupling photoinitiated free radical polymerization dimethacrylates in situ ion reduction. A polymerizable bearing a secondary amino functional group was used to increase the solubility salt hydrophobic resin system. Fourier transform infrared spectroscopy (FTIR) revealed that reduction had no significant effect on degree vinyl conversion methacrylate. X‐ray photoelectron (XPS)...
Architecturally similar monomers were copolymerized with a water–oil discriminate fluorosurfactant to create hydrophilic–oleophobic coatings. Acrylic acid, hydroxyethyl methacrylate, and methyl methacrylate used as comonomers the macromer. The homopolymers of selected are water-soluble, water-swellable, water-insoluble, respectively, thus coupling surfactant monomer in varying concentration within polymers hydrophilicity. Wetting behavior water hexadecane examined function copolymer...
Abstract A molecular layer‐by‐layer (mLbL) deposition process is demonstrated to synthesize conformal coatings of crosslinked polyamide. This controls the rapid reaction trimesoyl chloride and m ‐phenylene diamine, unlike interfacial polymerization techniques which produce rough films poorly defined network structure. Layer‐by‐layer polyamide appear structurally similar interfacially polymerized with a linear film growth rate ≈0.9 nm per cycle. Films made by mLbL show 70‐fold decrease in...
Cellulose nanocrystals (CNCs) are of increasing interest for packaging applications because their biodegradability, low cost, high crystallinity, and aspect ratio. The objective this study was to use positron annihilation lifetime spectroscopy (PALS) investigate the free volume CNC films with different structural arrangements (chiral nematic vs shear-oriented films) relate information gas barrier performance. It found that sheared higher alignment have lower hence more tortuosity than chiral...
Various polymer surfaces were analyzed for reactivity toward 3-aminopropyltriethoxysilane (APTES). Results indicate that the method described here is useful as a general surface-selective modification technique polar polymers such polyesters, polyamides, polycarbonates, polyimides, cellulosics, polyacrylics, etc. X-ray photoelectron spectroscopy (XPS) showed an average of 10% silicon and nitrogen atomic concentrations at 75° takeoff all successfully modified surfaces. The APTES multilayers...
Aromatic polyamide thin-film composite membranes are widely used in reverse osmosis (RO) and nanofiltration (NF) due to their high water permeability selectivity. However, these undergo biofouling can degrade eventually fail during free chlorine exposure. To better understand this effect, the reactivity of monomer (benzanilide (BA)) with was tested under varying pH chloride (Cl-) conditions. The kinetic results indicated that current existing mechanisms, especially Orton rearrangement, were...
Cellulose nanocrystals (CNCs) are promising materials for the packaging industry due to their nontoxicity, abundance in nature, biodegradability, and high gas barrier properties. Unfortunately, CNC films coatings suffer from brittleness, water sensitivity, and, similar polar polymers, loss of performance at elevated humidity. Citric acid is an inexpensive, nontoxic additive, a potential cross-linking agent, which can be utilized decreasing moisture sensitivity cellulose-based coating...
Cured-in-place-pipe (CIPP) technology has begun to be adopted for drinking water pipe repairs, and limited information exists about its quality impacts. CIPP involves the manufacture of a new plastic inside buried damaged pipe. In this study, chemical composition raw materials impacts were examined. Numerous (47) VOCs SVOCs found in resin two hardeners studied. TGA results indicated that CIPPs contained 3.2–4.8 wt% VOC. A controlled static headspace analysis using PTR-TOF-MS detected eight...
The development of polymers that are both bactericidal and biocompatible would have many applications currently research interest. Following the strongly copolymers 4-vinylpyridine poly(ethylene glycol) methyl ether methacrylate, biocompatibility assays been completed on these materials to measure their potential biocompatibility. In this article, a new methodology for measuring protein interaction was developed water-soluble by coupling proteins surfaces then adsorption onto surfaces....
Mechanical instabilities such as wrinkles, creases, and folds have long been viewed a source of frustration for engineers often point curiosity among scientists. Scientists aspire to understand the underlying physics behind formation mechanical how manipulate them various endeavours, while use this same understanding design materials that inhibit or impede in critical applications. In recent years, new movement community has emerged: harnessing these provide insight into properties soft...
Chemical emissions were characterized for steam-cured cured-in-place-pipe (CIPP) installations in Indiana (sanitary sewer) and California (stormwater). One pipe involved a low-volatile organic compound (VOC) non-styrene resin, while all other CIPP sites used styrene resins. In Indiana, the uncured resin contained styrene, benzaldehyde, butylated hydroxytoluene (BHT), unidentified compounds. Materials emitted from worksites condensed characterized. An chemical plume was complex multiphase...
ABSTRACT Epoxy thermosets have revolutionized the coating, adhesive, and composite industries but chemicals from which they are synthesized significant effects on environment human health not only precure also after crosslinking has occurred. In this study, we propose tannic acid (TA) as an alternative epoxy hardening agent for commercially available resin, diglycidyl ether of bisphenol A (DGEBA). The resulting were characterized by Fourier transform infrared spectroscopy, optical...
ABSTRACT Lignin was used as a biobased fill material to create epoxy composites. incorporated into diglycidyl ether of bisphenol A–based using hydration and Mannich functionalization. The effects chemical functionalization on the interfacial chemistry lignin are examined, corresponding changes in materials properties examined. Several types lignin–epoxy composites were formed through dissolution aliphatic amine. Lignin–amine solutions modified reaction cure epoxy. resulting exhibited...
Sustainable, non-halogenated flame retardants are desired for a variety of industry applications. Lignin, an industrially processed wood derivative, has been examined as potential sustainable retardant additive to polymer systems. Here, the lignin is phosphorylated using pyridine-catalysed esterification reaction with diphenyl phosphoryl chloride improve its char-forming abilities. The chemical modification was characterised by nuclear magnetic resonance spectroscopy and showed formation...
Ultraviolet light cured-in-place pipe is a popular trenchless rehabilitation technology used to repair existing buried pipelines without soil excavation. A polymer composite liner manufactured directly in the field. After curing complete, new placed service convey flowing water. Long-term water exposure has potential degrade fiber reinforced liners. Like other composites, hygrothermal stability could be major challenge, especially for undercured materials. The objective of this study was...