Block-Copolymer Assisted Fabrication Of Anisotropic Plasmonic Nanostructures,
2018
Missouri State University
Block-Copolymer Assisted Fabrication Of Anisotropic Plasmonic Nanostructures, Calbi J. Gunder
Graduate Theses/Dissertations
The anisotropic nanostructures of noble metals are of great interest for plasmonic applications due to the possibility of tuning the localized surface plasmon resonance (LSPR) across the UV-VIS-NIR without sacrificing the linewidth as well as to achieve larger local field enhancement. Here, we report a simple and promising fabrication method of anisotropic gold nanostructures film using polystyrene-b-2vinylpyridine (PS-b-P2VP) block copolymers (BCP) as a template. In this approach, PS-b-P2VP spherical micelles were first synthesized as a template followed by selective deposition of Au precursor inside P2VP core of the micelles using ethanol solution of Au salt. Subsequently, heat treatment of the …
Characterization Of Coacervate Systems Using Redox Sensitive Dyes,
2018
Central Washington University
Characterization Of Coacervate Systems Using Redox Sensitive Dyes, Caleb Kaiser
All Master's Theses
Coacervates are systems that spontaneously form when two oppositely charged polyelectrolytes are mixed in a concentrated salt solution. When coacervates form, a biphasic equilibrium occurs in the sample with two phases present in the solution. The two phases are described as the dense phase and the lean phase, named after the amount of polyelectrolyte material in each phase. Coacervates have been topics of interest to researchers in a variety of fields including biomedical applications, drug delivery devices, and more. This thesis worked towards the characterization of coacervate systems on the molecular level by investigating the interaction of the polyelectrolytes and …
Fabrication Of Superhydrophobic Gold Film On Polymer Substrates,
2018
Faculty of Sciences
Fabrication Of Superhydrophobic Gold Film On Polymer Substrates, Siriwan Boonmeewiriya
Chulalongkorn University Theses and Dissertations (Chula ETD)
Superhydrophobic surface was fabricated by a reduction reaction between chloroauric acid (HAuCl4) and sodium formate (HCOONa) on polydimethylsiloxane (PDMS) substrate without any further surface modification. This generated gold films with superhydrophobic properties examined by water contact angle (WCA) and contact angle hysteresis measurement. Wettability of the fabricated gold film on PDMS substrate can be controlled by the deposition time which provides the WCA > 160o and it could be up to 164.41o with a contact angle hysteresis of 1.93o when the deposition time was prolonged at least 2 hours. To propose the deposition mechanism, the morphological structure and chemical characters of …
Functionalizing Titanium Implants With Bioactive Peptides To Increase Osseointegration,
2018
The University of Akron
Functionalizing Titanium Implants With Bioactive Peptides To Increase Osseointegration, Neil Bernard
Williams Honors College, Honors Research Projects
Orthopedic surgeries have continued to increase, but the material of choice remains constant: titanium. Titanium has become the benchmark implant material due to its durability and non-immunogenic properties. However, while high rates of success are correlated with joint replacement surgery, certain patients with predisposed diseases such as diabetes or arthritis may have increased complications.1 This can be due to lack of osseointegration due to decreased bone formation and mineralization,2 which will lead to increased rates of infection or aseptic loosening of the implant from the bone. 3 Current methods to alleviate these complications include invasive revisional surgeries, which …
Multi-Dimensional Mass Spectrometry For The Characterization Of Glycopolymers,
2018
The University of Akron
Multi-Dimensional Mass Spectrometry For The Characterization Of Glycopolymers, Maria Ganios
Williams Honors College, Honors Research Projects
Several glycopolymers synthesized by Activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP), were characterized by mass spectrometry to elucidate their microstructure and architecture. Analyses were performed using Matrix Assisted Laser Desorption Ionization- Time of Flight/ Time of Flight (MALDI-ToF/ToF) and Electrospray Ionization Mass Spectrometry (ESI-MS) instruments. The linear isopropylidenated glycopolymer (P65B1) analyzed with ESI-MS also was examined with multi-stage mass spectrometry (MSn) using collision induced dissociation (CID) to examine the tetramer parent ion. This glycopolymer was found to be either cyclic or linear (sans end groups) due to the data being fit for both forms …
Preparation Of Polyurethane And Polyisocyanurate Foams Catalyzed By Metal Acetate-Ammonia Complexes,
2018
Faculty of Sciences
Preparation Of Polyurethane And Polyisocyanurate Foams Catalyzed By Metal Acetate-Ammonia Complexes, Benjatham Sukkaneewat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Metal acetate-ammonia complex solutions, namely Cu(Amm) and Zn(Amm), were synthesized and characterized by UV-visible spectroscopy and MALDI-TOF mass spectrometry. Cu(Amm) and Zn(Amm) were used as homogeneous catalysts for accelerating gelling (urethane formation) and blowing reactions (CO2 generation) of rigid polyurethane (RPUR) and polyisocyanurate (PIR) foams. Potassium octoate solution in diethylene glycol, which was used as a trimerization catalyst, was mixed with Cu(Amm) or Zn(Amm) to give a catalyst mixture which can catalyze gelling, blowing and trimerization reactions for the preparation of PIR foams. The catalytic activity of Cu(Amm) and Zn(Amm) in gelling and blowing reactions was compared to that of …
Pdms-Silver Nanocomposite For Bendable And Stretchable Conductive Stripes,
2018
Faculty of Science
Pdms-Silver Nanocomposite For Bendable And Stretchable Conductive Stripes, Porapak Suriya
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, a simple and low-cost protocol for fabricating PDMS-silver composite as flexible conductive polymer is presented. Rod-shaped silver acetate (RS-AcOAg) was synthesized and fabricated into a solvent-cast RS-AcOAg film. The film was thermally decomposed into porous silver structures at 300ºC. The thermal decomposition of RS-AcOAg film induced the formation of silver microparticles (AgNPs) on the surface of RS-AcOAg with the expense of RS-AcOAg rod. AgNPs sintered into bigger particles and turned RS-AcOAg film into porous silver film consisting of interconnected quasi-sphere silver microparticles (AgMPs). The sintered structures transformed porous silver into rigid structures and affected the electrical resistivity …
Enhanced Analysis Of Lignin Dehydrogenation Oligomers Via Mass Spectrometry,
2018
University of Kentucky
Enhanced Analysis Of Lignin Dehydrogenation Oligomers Via Mass Spectrometry, Amber Suzanne Bowman
Theses and Dissertations--Chemistry
Effective analytical techniques need to be developed to characterize the products of lignin degradation experiments to be able to generate renewable products from lignin. Mass spectrometry is an valuable analytical approach for lignin characterizaion, but it is hindered by lignin’s poor ionization efficiency, especially in the positive ion mode. In this work, we attempt to improve lignin’s ionization by utilizing electrospray and laser desorption mass spectrometry coupled with the addition of cations and chemical derivatives. We confronted the ionization problem from both a top-down and bottom-up analytical approach by analyzing synthesized monomers, dimers, and polymers along with natural lignin extracts …
Study Of The Effect Of Steric Bulk Of Side Chains On The Properties Of Conjugated Polymers,
2018
University of Kentucky
Study Of The Effect Of Steric Bulk Of Side Chains On The Properties Of Conjugated Polymers, Bei Zhang
Theses and Dissertations--Chemistry
Donor-acceptor conjugated polymers opened a new era for conjugated polymer research due to the abundant selection and combination of different conjugated units. This class of polymers function as semiconductor materials with potential application in plastic consumer electronics. The frontier molecular orbital energies of the polymers are generally determined by the selection of donor and acceptor units in the backbone structure, and their substituents. The side chains attached to the backbone not only affect the solubility of the materials, but also their self-assembly and morphological characteristics, which indirectly govern optoelectronic properties. It is important therefore to consider backbone architectures and the …
Modification Of Screen-Printed Carbon Electrode With Mxene/Conductive Polymer Composites For Hydrogen Peroxide Detection,
2018
Faculty of Science
Modification Of Screen-Printed Carbon Electrode With Mxene/Conductive Polymer Composites For Hydrogen Peroxide Detection, Supawat Neampet
Chulalongkorn University Theses and Dissertations (Chula ETD)
MXene (Ti3C2), a two-dimensional material consisting of transition metal carbides, nitrides or carbonitrides was prepared by etching method for modification electrode of a novel nanocomposites consisting of platinum nanoparticles (PtNPs) and polyaniline (PANI) via electrodeposition and electropolymerization, respectively. The fabricated MXene/PANI/PtNPs nanocomposite modified on surface screen-printed carbon electrode (SPCE) were characterized by scanning electron microscopy SEM) with energy dispersive X-rays spectroscopy (EDX), X-ray powder diffraction (XRD), and transmission electron microscopy (TEM) to verify the presence of nanocomposite materials and indicate their morphologies. This electrode was applied for the detection of hydrogen peroxide (H2O2), which is a common electroactive product from …
Polyisocyanurate Foams Preparation Catalyzed By Mixtures Of Copper-Amine Complexes/Potassium 2-Ethylhexanoate,
2018
Faculty of Science
Polyisocyanurate Foams Preparation Catalyzed By Mixtures Of Copper-Amine Complexes/Potassium 2-Ethylhexanoate, Teeraporn Suwannawet
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, a new catalyst system for the preparation of polyisocyanurate (PIR) foam was developed. The mixture of copper-amine complex:potassium 2-ethylhexanoate (K-15) and metal-ethanolamine complex:K-15 were used as catalysts. Two copper-amine complexes and two metal-ethanolamine complexes, namely Cu(OAc)2(en)2, Cu(OAc)2(trien), Cu(OAc)2(EA)2 and Zn(OAc)2(EA)2, respectively; where en = ethylene diamine, trien = triethylenetetramine and EA = ethanolamine, were used as catalyst for blowing and gelling reactions. K-15 was used as a catalyst for trimerization reaction. These catalysts could be further used in the preparation of PIR forms without purification. Characterization of catalysts were done by using UV-visible spectroscopy. The factors investigated …
Improved Barrier Properties Of Pp/Ldpe Composite Film: Effect Of Montmorillonite And Poly (Lactic Acid),
2018
Faculty of Sciences
Improved Barrier Properties Of Pp/Ldpe Composite Film: Effect Of Montmorillonite And Poly (Lactic Acid), Supornpat Mooninta
Chulalongkorn University Theses and Dissertations (Chula ETD)
In this research, the properties of polypropylene (PP) were improved for single layer film application by incorporating low density polyethylene (LDPE), poly(lactic acid) (PLA) and montmorillonite (MMT). The polymer composites was prepared by melt blending using a twin screw extruder and the film was produced by cast film extruder. The addition of LDPE in PP improved the elongation at break and tear strength. The PP/LDPE blend at the ratio of 80:20 (w/w) was selected for blending with PLA and MMT and the PP/LDPE/PLA/MMT composite showed the increased tensile modulus while the elongation at break decreased with increasing PLA and MMT …
Surface-Enhanced Raman Scattering Technique For Polycyclic Aromatic Hydrocarbons Detection Using Thiol-Functionalized Silver Nanoparticle Films,
2018
Faculty of Science
Surface-Enhanced Raman Scattering Technique For Polycyclic Aromatic Hydrocarbons Detection Using Thiol-Functionalized Silver Nanoparticle Films, Sathita Taksadej
Chulalongkorn University Theses and Dissertations (Chula ETD)
The detection of polycyclic aromatic hydrocarbons (PAHs) is developed based on surface-enhanced Raman scattering (SERS) using silver nanoparticle films as SERS substrates. The films are fabricated by a Langmuir Blodgett (LB) method and the surface of AgNP films are functionalized with various types of aromatic and aliphatic thiols, i.e., naphthalenethiol, phenylethanethiol, pentanethiol, octanethiol, and dodecanethiol, to create a hydrophobic layer for PAHs to attach on and stay in hot spot. The results indicate that nine kinds of PAHs with different structures, i.e., anthracene, chrysene, naphthacene, naphthalene, phenanthrene, pentacene, perylene, pyrene, and triphenylene, can attach on the surfaces of thiol-modified AgNP …
Preparation And Characterization Of Starch Films Reinforced With Citrate Cellulose Nanocrystals,
2018
Faculty of Sciences
Preparation And Characterization Of Starch Films Reinforced With Citrate Cellulose Nanocrystals, Prapaporn Nakarat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Citrate-modified bacterial cellulose nanocrystals (citrate CNCs) were prepared by a green one-pot dual acid (citric and hydrochloric acids) method and used them to reinforce three types of starch films; corn, wheat and rice starch films. The average length and width of citrate CNCs were 583 and 46 nm, respectively. The degree of citrate substitution on CNCs was 0.075 and its crystallinity index was closely to the original bacterial cellulose. The effect of various amount of citrate CNCs (0-20%wt of starch) on film property was study. Three starch films showed the same trend of examination results. The film thickness of most …
Preparation Of Alginate Capsule Using Two Coaxial Glass-Tube,
2018
Faculty of Sciences
Preparation Of Alginate Capsule Using Two Coaxial Glass-Tube, Panida Watchanung
Chulalongkorn University Theses and Dissertations (Chula ETD)
TEMPO-Oxidized bacterial cellulose (TOBC) were obtained using TEMPO-mediated oxidation (TOBC) to produce carboxylate groups on bacterial cellulose surfaces. TOBC had lower crystallinity but better aqueous dispersion than bacterial cellulose. TOBC was used as a reinforcement agent for production alginate capsules. The alginate capsules for entrapping rice bran oil were made via a coaxial-glass tube. The factors that influenced on the shape and production efficiency of capsules were the gap between tube tip and the Ca2+ ions bath and the viscosity of shell solution. However, these factors had no effect on the size and shell thickness of capsules. Increasing of TOBC …
Sustained Release Of Antibiotics From Bone Spacer,
2018
Faculty of Science
Sustained Release Of Antibiotics From Bone Spacer, Miranda Oungeun
Chulalongkorn University Theses and Dissertations (Chula ETD)
Bone spacer is a device developed to temporarily insert into the body to treat infected tissue caused by bone replacement. Burst release and short-time release of antibiotics from bone spacer not only limits their ability to clear infection but also causes tissue inflammation. Therefore, here we have fabricated bone spacers containing antibiotic-loaded particles, studied their antibiotic release character, and measured the compressive strength of PMMA cements. Four biocompatible particles were investigated. Vancomycin and erythromycin were used as hydrophilic and hydrophobic model drugs, respectively. Rice granules and calcium citrate particles were loaded with vancomycin and gave the percent loading of 84.9 …
การเตรียมขั้วแอโนดเชิงประกอบของสังกะสี/พอลิพิร์โรล/รีดิวซ์แกรฟีนออกไซด์สำหรับแบตเตอรีสังกะสีไอออน,
2018
คณะวิทยาศาสตร์
การเตรียมขั้วแอโนดเชิงประกอบของสังกะสี/พอลิพิร์โรล/รีดิวซ์แกรฟีนออกไซด์สำหรับแบตเตอรีสังกะสีไอออน, วีระพงษ์ นวลวัฒน์
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้มีวัตถุประสงค์เพื่อศึกษาสัดส่วนที่เหมาะสมในการเตรียมขั้วแอโนดเชิงประกอบของสังกะสี/พอลิพิร์โรล/รีดิวซ์แกรฟีนออกไซด์ และศึกษาสมบัติทางไฟฟ้าเคมีของขั้วเชิงประกอบที่เตรียมได้เพื่อใช้เป็นขั้วแอโนดในระบบแบตเตอรีสังกะสีไอออนโดยทำการศึกษาจำนวนรอบในการสังเคราะห์พอลิพีร์โรลโดยเทคนิคไซคลิกโวแทมเมทรีที่จำนวนรอบ 0, 3, 5 และ 7 รอบ และความเข้มข้นของแกรฟีนออกไซด์ที่ใช้ในการฝังตัวร่วมทางเคมีไฟฟ้าที่ 0.01, 0.05 และ 0.1 กรัมต่อมิลลิลิตร ลักษณะสัณฐานวิทยาบริเวณพื้นผิวของขั้วแอโนดสังกะสีห่อหุ้มด้วยพอลิพิร์โรล/รีดิวซ์แกรฟีนออกไซด์ที่เตรียมได้ถูกตรวจสอบด้วยกล้องจุลทรรศน์อิเล็กตรอนแบบส่องกราด พบการปกคลุมผิวของพอลิพิร์โรลและการแทรกตัวของรีดิวซ์แกรฟีนออกไซด์อยู่บนพื้นผิวของผิวสังกะสี ระนาบผลึกของสังกะสี/พอลิพิร์โรล/รีดิวซ์แกรฟีนออกไซด์ถูกยืนยันด้วยเทคนิคเอกซ์เรย์ดิฟแฟรกชันสเปกโทรสโกปี สมบัติทางไฟฟ้าเคมีสามารถตรวจสอบได้โดยเทคนิคไซคลิกโวลแทมเมทรี จากการศึกษาพฤติกรรมการกัดกร่อนทางเคมีไฟฟ้า พบว่า ขั้วแอโนดสังกะสีห่อหุ้มด้วยพอลิพิร์โรลจำนวนรอบการสังเคราะห์ที่ 5 รอบ และใช้แกรฟีนออกไซด์ที่ความเข้มข้น 0.05 กรัมต่อมิลลิลิตร สามารถให้ค่าประสิทธิภาพการยับยั้งการกัดกร่อนที่ดีที่สุดถึงร้อยละ 69.88 และเมื่อนำไปทดสอบหาค่าความสามารถในการเก็บประจุโดยเทคนิคกัลป์วาโนสแตติกชาร์ท-ดิสชาร์ท ที่กระแสไฟฟ้า 0.1 แอมแปร์ต่อกรัม ในสารละลายซิงค์ซัลเฟต 2 โมลาร์ พบว่าสามารถในการเก็บประจุสูงถึง 325.69 มิลลิแอมแปร์ชั่วโมงต่อกรัม และเมื่อนำไปทดสอบเสถียรภาพต่อรอบ พบว่าขั้วไฟฟ้าแอโนดสังกะสีห่อหุ้มด้วยพอลิพิร์โรล/รีดิวซ์แกรฟีนออกไซด์ความเข้มข้นที่ 0.05 มีวัฎจักรชีวิตที่สามารถให้ประสิทธภาพต่อรอบสูงที่สุดโดยคงประสิทธิภาพอยู่ที่ร้อยละ 41.83 หลังการอัดและคายประจุพลังงานไฟฟ้าที่ 50 รอบ ผลการทดลองนี้ชี้ให้เห็นว่าวัสดุขั้วแอดโนดชนิดนี้สามารถนำไปประยุกต์ในแบตเตอรีสังกะสีไอออนที่มีประสิทธิภาพสูงได้
การพัฒนาผ้าที่มีสมบัติป้องกันการรบกวนทางแม่เหล็กไฟฟ้า,
2018
คณะวิทยาศาสตร์
การพัฒนาผ้าที่มีสมบัติป้องกันการรบกวนทางแม่เหล็กไฟฟ้า, สิรภพ ถาวร
Chulalongkorn University Theses and Dissertations (Chula ETD)
งานวิจัยนี้ศึกษาประสิทธิภาพปิดกั้นสนามแม่เหล็กไฟฟ้าผ่านการวัดค่าความต้านทานไฟฟ้าของพอลิอะนิลีนที่เคลือบลงบนซับสเตรตสองชนิดอันได้แก่ ผ้าเอ็มอะรามิดและผ้าเอ็มอะรามิดที่ถูกดัดแปรผ่านปฏิกิริยาไนเตรชัน/รีดักชัน โดยใช้ความเข้มข้นของอะนิลีนมอนอเมอร์ที่ 1% ถึง 20% โดยปริมาตร อีกทั้งศึกษาผลของการซักและการโดปที่ภาวะต่างๆ แล้วนำไปทดสอบสมบัติต่างๆ คือการวัดค่าความต้านทานไฟฟ้า ความแข็งกระด้างเมื่อดัดโค้ง และความคงทนของสีต่อการซัก จากผลการทดลองได้ภาวะที่เหมาะสมที่ทำให้ได้ผ้าที่มีสมบัติป้องกันการรบกวนทางแม่เหล็กไฟฟ้าคือการเคลือบพอลิอะนิลีน ที่ความเข้มข้นอะนิลีนมอนอเมอร์ 10% ลงบนผ้าเอ็มอะรามิดที่ไม่ได้ดัดแปร ให้ค่าความต้านทานที่ผิวอยู่ที่ 0.034 กิโลโอห์มต่อตาราง คิดเป็นประสิทธิภาพปิดกั้นสนามแม่เหล็กไฟฟ้าอยู่ที่ 20.99 เดซิเบล ภายหลังการซักและการโดปซ้ำ ประสิทธิภาพปิดกั้นมีแนวโน้มลดลงในทุกกรณี ในกรณีที่เคลือบที่ความเข้มข้น 10% โดยปริมาตร ความแข็งกระด้างดัดโค้งมีค่า 204.60 มิลลิกรัมเซนติเมตร การเปื้อนติดภายหลังการซักอยู่ที่ระดับ 5
Preparation Of Coating Materials With Antifungal Property From Hemp Nanocellulose And Clove Essential Oil Nanoemulsions,
2018
Faculty of Science
Preparation Of Coating Materials With Antifungal Property From Hemp Nanocellulose And Clove Essential Oil Nanoemulsions, Papatsorn Rattanapet
Chulalongkorn University Theses and Dissertations (Chula ETD)
This research aimed to offer an alternative solution to solve Black stripe disease in rubber tree which causes by Phytophthora palmivora by preparing antifungal coating materials from hemp nanocellulose and clove essential oil nanoemulsion. Hemp nanocellulose was used as a matrix which prepared by chemi-mechanical method that hemp was treated with alkaline and bleaching solution before being reduced hemp fibers into nanoscale by microfluidization. Antifungal property of coating materials was developed by the addition of clove essential oil nanoemulsion which prepared by spontaneous emulsification. Tween 20, Span 20, and coconut oil were used as main surfactant, co-surfactant, and carrier oil. …
Halogenated Parabens And Halogenated Phenoxyethanols As Antibacterial Agents In Cushion Products,
2018
Faculty of Science
Halogenated Parabens And Halogenated Phenoxyethanols As Antibacterial Agents In Cushion Products, Lalisa Dechnitirat
Chulalongkorn University Theses and Dissertations (Chula ETD)
Halogenated compounds are interesting as antimicrobial agents for cosmetic product. The bromination of methyl paraben and 2-phenoxyethanol were carried out under mild conditions using NaBr and 30% H2O2 yielding methyl 3,5-dibromo-4-hydroxybenzoate and p-bromo-2-phenoxyethanol, respectively. Three parameters including the ratio of brominating agent and oxidizing agent, type of solvents, and temperature were optimized. These synthesized products were used as antibacterial agent in cushion product as individual or blend. The challenge test results revealed that methyl 3,5-dibromo-4-hydroxybenzoate and p-bromo-2-phenoxyethanol could effectively inhibit Staphylococcus aureus, Candida. albicans, and Aspergillus brasiliensis more than their parents. For stability test, there was no change of the …
