Polymer Chemistry Commons^™

Synthesis Of Poly(Styrene-Co-Butyl Acrylate) Pickering Emulsion With Montmorillonite Nanoparticles And Its Comparison With Sodium Dodecyl Sulfate Surfactant On Affecting The Water Barrier Properties Of Coated Paper, Chidubem H. Uchefuna

Electronic Theses and Dissertations

Water-borne barrier dispersion coatings on paper have emerged as an alternative to extrusion coatings on paper due to improved recycling, high application speed, and other end of life attributes. Pigments are often added to improve the performance of dispersion coatings. The use of pigments to form a Pickering emulsion during the polymerization step for the production of a barrier coating on paper has not been discussed in the literature.

In this study, montmorillonite (MMT) pigment varied from 0-6 % pigment volume concentration (PVC) was used to synthesize dispersion coatings consisting of poly(styrene-co-butylacrylate) latex and compared with sodium dodecyl …

Functionalized 𝜹-Hexalactones (Fdhls): Bio-Derivable Monomers To Synthesize Renewable Polyester Thermoplastics, Atik Faysal

Electronic Theses and Dissertations

Most thermoplastics are made from limited fossil-fuel sources and these plastics have very deleterious impacts on the environment. Finding a renewable source to synthesize new thermoplastic polymers with tunable properties like biodegradability, heat resistance, and moisture resistance are ongoing research interests. Lignocellulosic biomass is a promising renewable feedstock for biobased monomers and polymers production. In this work, functionalized 𝛿-hexalactone (FDHL) monomers are hypothesized to be synthesizable from lignocellulosic sourced hydroxymethyl furfural (HMF) and lignin-derived pendant groups, generating a variety of aliphatic polyesters and potentially overcome current polymer challenges. Achieving a higher glass transition temperature (T_g) is one of …

Polysaccharide And Silver Nanoparticles Based Hydrogels, Porous Materials, And Sensors, Muhammad R. Hossen

Electronic Theses and Dissertations

Cellulose based hydrogels and porous materials are gaining significant attention across a wide range of applications due to the natural abundance, biodegradability and physicochemical tunability of this polysaccharide. Cellulose nanofibrils (CNF) outperform cellulose fibers in terms of physicochemical tunability since CNF possess relatively high surface area. However, superior dispersibility of CNF in aqueous phase makes it challenging for traditional methods to dewater CNF suspensions to fabricate robust hydrogels and porous materials. In this dissertation, a novel scalable capillary based method to dewater CNF suspensions is invented as well as CNF hydrogels and porous materials with a broad range of porosity …

Biomass Based Monomers For Synthesis Of Renewably Sourced Polymers, Anushka E. Vithanage

Electronic Theses and Dissertations

Limited fossil resources have raised research focus on synthesizing novel, sustainable polymers and renewably sourcing existing petroleum based polymers. This work presents the synthesis and ring opening polymerization (ROP) of a new functionalized lactone monomer, methoxy-δ-hexalactone (MDHL), to yield a functionalized polyester (polyMDHL). MDHL can be renewably sourced from hydroxymethylfurfural, a renewable platform chemical. MDHL was synthesized from methyl cyclopentanone-2-carboxylate by a five-step synthesis with a global yield of 23%. ROP of MDHL was conducted with benzyl alcohol initiator, catalyzed by diphenyl phosphate. 1H Nuclear Magnetic Resonance spectroscopy verified polyMDHL chemical structure. Targeting higher molecular weights for polyMDHL by increasing …

Chemically Cross-Linked Polysaccharide-Based Hydrogels Via Thiol-Norbornene Reaction As Sustainable Biomaterials, Nayereh Dadoo

Electronic Theses and Dissertations

Hydrogels are 3D polymeric networks with high water content and are widely being investigated for biomedical applications such as tissue engineering. Polysaccharides have been used to fabricate hydrogels due to their natural abundance, biocompatibility, and immunogeniety. Additionally, polysaccharide-based hydrogels can provide mechanical and biological cues similar to those of the natural environments. In this work, thiol-norbornene chemistry was used to fabricate polysaccharide-based hydrogels including hyaluronic acid (HA), carboxymethyl cellulose (CMC), and cellulose nanofibrils (CNFs). Hydrogels with tunable physical and mechanical properties were achieved. The properties of these hydrogels were spatiotemporally modified by photopatterning. Also, high stem cell viability was achieved …

Cellulose Nanofiber-Reinforced Impact Modified Polypropylene: Assessing Material Properties From Fused Layer Modeling And Injection Molding Processing, Jordan Elliott Sanders

Electronic Theses and Dissertations

The purpose of this research was to investigate the use of cellulose nanofibers (CNF) compounded into an impact modified polypropylene (IMPP) matrix. A IMPP was used because it shrinks less than a PP homopolymer during FLM processing. An assessment of material properties from fused layer modeling (FLM), an additive manufacturing (AM) method, and injection molding (IM) was conducted. Results showed that material property measurements in neat PP were statistically similar between IM and FLM for density, strain at yield and flexural stiffness. Additionally, PP plus the coupling agent maleic anhydride (MA) showed statistically similar results in comparison of IM and …

Exfoliated Graphite Nanoplatelet-Filled Impact Modified Polypropylene Nanocomposites, Alex Duguay

Electronic Theses and Dissertations

Exfoliated graphite nanoplatelets (xGnP)-filled polymer composites have demonstrated superior electrical, mechanical, physical and thermal properties and are becoming a major focus for both academic and industrial research and development (R&D) activities. The main objective of this study was to characterize the influence of xGnP particle diameter, filler loading and the addition of coupling agents on the mechanical, rheological and thermal properties of xGnP-filled impact modified polypropylene (IMPP) composites. IMPP is currently being used at the AEWC Advanced Structures and Composites Center in polymer impregnated (pre-preg) fiber reinforced polymer (FRP) tapes consisting of an IMPP matrix polymer and E-glass continuous fibers. …

Sger: Supercritical Levitation Polymerization And Processing, Erdogan Kiran

University of Maine Office of Research Administration: Grant Reports

In supercritical polymerization processes, polymer chains grow to molecular weights determined by their solubility under the prevailing density (or pressure and temperature) conditions of the solvent. Further growth in the chain length results in phase separation and leads to precipitation. In this project, polymerizations will be conducted under isopycnic conditions by adjusting the density of the solvent environment to be identical to the density of the polymer formed. This iso- density operation is expected to insure levitation by buoyancy and prevent precipitation of the phase-separated polymer. Density adjustments are readily achievable for supercritical solvents through manipulation of either the pressure …

Ir Studies Of The Interaction Of Surfactants And Polyelectrolytes Adsorbed On Tio2 Particles, Haiyan Li

Electronic Theses and Dissertations

Polymers/surfactants are used to control and modify the interfacial properties of particulate suspensions. The resulting properties are dependent on the amount of adsorbed surfactants/polymers on the surface as well as the nature of the aggregated structures. Often these interactions are complex and not well understood. In this thesis we have used Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) to identify surfactant, mixed surfactant, polyelectrolyte and mixed polyelectrolyte surfactant structures formed on charged Ti0₂ particles. In addition, the change occurring to the structure of an adsorbed polymer layer on Ti0₂ to flowing suspension of silica particles was studied. A …

Impact Of Preservative Treatments And Fungal Exposure On Phenolic Fiber Reinforced Polymer (Frp) Composite Material Utilized In Wood Reinforcement, Cihat Tascioglu

Electronic Theses and Dissertations

When wood products are exposed to environmental conditions conducive to biodeterioration, wood preservation becomes a necessity, especially when long-term utilization is desired. Although considerable literature exists on the treatment of laminated timbers and wood composites with wood preservatives, almost no information is available on the exposure of Fiber Reinforced Polymer (FRP) composites to wood preservative chemicals. In this work, FRP material was treated with common preservative chemicals and the effect of wood preservative treatments on mechanical properties of FRP material were investigated. Although the longitudinal elastic modulus was unaffected, some longitudinal strength losses were recorded for CCA and CDDC (water …