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Xiong, Cher. "A study of two-component clear casting urethanes, urethane catalysts, and related processes". Online version, 1998. http://www.uwstout.edu/lib/thesis/1998/1998xiongc.pdf.
Pełny tekst źródłaClayton, Anthony Brian. "Photopolymerised urethane acrylates /". Title page, contents and summary only, 1992. http://web4.library.adelaide.edu.au/theses/09PH/09phc622.pdf.
Pełny tekst źródłaAlshuiref, Abubaker. "Synthesis and characterization of two novel urethane macromonomers and their methacrylic/urethane graft copolymers". Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4022.
Pełny tekst źródłaENGLISH ABSTRACT: Polymethacrylates are well known adhesives and can carry specific functionality, but have the disadvantage that their flexible backbones impart limited thermal stability and mechanical strength. Polyurethanes (PUs) are finding increasing application and use in many industries due to their advantageous properties, such as a wide range of flexibility combined with toughness, high chemical resistance and excellent weatherability. PUs do however have some disadvantages, for instance, PU is considered an expensive polymer, especially when considered for solvent based adhesives. the focus of this study was to consider a largely unstudied area of PU chemistry, namely combining PUs with polymethacrylates. Two types of linear urethane macromers (UMs) UM1 and UM2 were synthesized by the polyaddition polymerization of 4,4'-methylenediphenyl diisocyanate (MDI) with ethylene glycol (EG), and MDI with neopentylglycol (NPG), via a pre-polymer method, followed by termination with 2-hydroxy ethylacrylate (2-HEA) and methanol (MeOH) to yield UMs having specific urethane chain lengths, and which have to be predominantly monofunctional. Structural identification of the UMs was verified by MALDI-TOF-MS, FTIR, 13C-NMR and 1HNMR spectroscopy.Various percentages of the respective UMs (0_55 wt % of methacrylate monomers) were then incorporated into polymethyl methacrylate (PMMA) and poly n-butyl methacrylate (PnBMA) backbones via solution free-radical copolymerization. The resulting methyl methacrylate-g-urethane and n-butyl methacrylate-g-urethane copolymers were characterized by 1H-NMR,13C-NMR, FTIR, SEC with double detectors (UV and RI), light scattering, UV-Vis, HPLC, TGA, DSC, DMA and TEM. Weight percentages of UM incorporated into the methyl methacrylate-g-urethane copolymers were calculated using FTIR, UV-Vis and 1H-NMR techniques. Phase separation which occurred between the urethane segment and methacrylate segment in the graft copolymerization products was investigated by DMA, DSC and TEM analysis. Microphase separation occurred in all PMMA-g-UM1 and PnBMA-g-UM1 copolymers: two glass transitions temperatures corresponding to the PMMA or PnBMA and UM1 fractions, respectively, were observed. On the other hand, DMA and DSC results showed that in most graft copolymer products the two respective component parts PMMA-g-UM2 or PnBMA-g- UM2 were compatible, because only one Tg was observed. Two glass transitions occurred for PMMA or PnBMA and UM2 when the amount of UM was increased to 55 wt % during copolymerization and microphase separation was evident in DSC, DMA and TEM measurements. Thermal stability and storage modulus (stiffness) of all the synthesized PMMA-g-urethane and PnBMA-g-urethane copolymers increased as the concentration of urethane macromonomer in the copolymerization feed increased, as confirmed in TGA and DMA results. The surface and adhesive properties of the synthesized graft copolymer were studied by measuring the static contact angle and peel strength. Adhesion increased as the content of UMs increased in the graft copolymer. The graft copolymers prepared using a high UM2 feed for both PMMA and PnBMA showed improved in adhesion compared to the pure methacrylate polymers. The adhesion was better for both leather and for vinyl.
AFRIKAANSE OPSOMMING: Polimetakrilate is bekende kleefstowwe. Hulle het egter die tekortkoming dat hulle buigbare ruggraat beperkte termiese en meganiese stabliteit besit. Poliuretane (PUs) word deesdae al hoe meer gebruik in baie nywerhede as gevolg van hulle baie voordele, insluitend hul wye buigsaamheid tesame met sterkte, hoë chemiese weerstand en uitstekende weerbaarheid. PUs het egter ’n paar nadele: hulle is baie duur, veral wanneer hulle gebruik word in oplosmiddel-gebaseerde kleefstowwe. Die doel van hierdie studie is om die kombinering van PUs met polimetakrilate te bestudeer, 'n onderwerp wat tot dusver baie min aandag-getrek het. Twee tipes liniêre uretaanmakromere (UMs), UM1 en UM2, is gesintetiseer deur gebruik te maak van poliaddisiepolimerisasie van 4,4'-metileendifeniel diisosianaat (MDI) met etileenglikol (EG), en MDI met neopentielglikol (NPG), via ‘n prepolimeermetode, gevolg deur terminering met 2-hidroksiëtielakrilaat (2-HEA) en metanol (MeOH). Die produk hiervan is UMs met spesifieke kettinglengtes (hoofsaaklik monofunksioneel). Die samestelling van die UMs is met behulp van die volgende gevorderde analitiese tegnieke bepaal: MALDI-TOFMS, FTIR, 13C-NMR en 1H-NMR. Verskillende hoeveelhede van die UMs (0_55 gewIing% metakrilaatmonomere) is dan in die polimetielmetakrilaat (PMMA) en poli-n-butielmetakrilaat (PnBMA) ruggrate geïnkorporeer deur middel van oplossing-vryradikaalpolimerisasie. Die samestelling van die kopolimeerprodukte, metiel-metakrilaat-g-uretaan en n-butiel-metakrilaat-g-uretaan, is met behulp van die volgende gevorderde analitiese tegnieke bepaal: 1H-NMR, 13C-NMR, FTIR, SEC met dubbele detektors (UV en RI), ligverstrooiing UV-Vis, HPLC, TGA, DSC, DMA en TEM. Die hoeveelheid UM geïnkorporeer in die metielmetakrilaat-g-uretaan kopolimere is bereken deur gebruik te maak van FTIR, UV-Vis en 1H-NMR data. Die faseskeiding wat plaasgevind het tussen die uretaansegment en die metakrilaatsegment in die produkte van die entpolimerisasie is met behulp van DMA, DSC en TEM ondersoek. In alle PMMA-g-UM1 en PnBMA-g-UM1 kopolimere het mikrofaseskeiding plaasgevind: twee verskillende glasoorgangstemperature vir die PMMA of PnBMA en UM1 fraksies is waargeneem. Hierteenoor het DMA en DSC resultate getoon dat in die meeste entkopolimeerprodukte (PMMA-g-UM2 of PnBMA-g-UM2) was die twee komponente verenigbaar, aangesien net een Tg waargeneem is. In die geval van die kopolimere waar die hoeveelheid UM in die kopolimerisasiereaksies tot 55 gew% verhoog is, is twee glasoorgangstemperature vir PMMA of PnBMA, en UM2 waargeneem. Mikrofaseskeiding is met behulp van DSC, DMA en TEM bewys. Termiese stabiliteit en stoormodulus (styfheid) van alle gesintetiseerde PMMA-g uretaan en PnBMA-g-uretaan kopolimere het toegeneem namate die uretaankonsentrasie in die kopolimerisasiereaksie toegeneem het soos deur middel van TGA en DMA resultate bewys is. Die oppervlakte- en kleefeienskappe van die bereide entkopolimere is bestudeer deur die statiese-kontakhoek en skilkrag te meet. Adhesie het toegeneem namate die UMinhoud toegeneem het. Die entkopolimere berei met hoë PMMA en PnBMA inhoud het uiteindelik beter adhesie getoon as die suiwer metakrilaatpolimere. Die adhesie was beter vir beide leer en viniel.
Cobaj, Anisa. "The Effects of Urethane Methacrylates on the Film Properties of Acrylic-Urethane Hybrid Latexes". University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1560335362557041.
Pełny tekst źródłaKitson, Sean Leslie. "The mechanism of carcinogenesis by urethane". Thesis, University of Newcastle Upon Tyne, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242359.
Pełny tekst źródłaZhang, Xiangcheng. "Fracture of modified urethane-methacrylate resins". Thesis, Cranfield University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358297.
Pełny tekst źródłaVan, Clack Ralph Vincent. "Non-isocyanate routes to urethane-polymers". Thesis, University of Central Lancashire, 2007. http://clok.uclan.ac.uk/20700/.
Pełny tekst źródłaDegrandi, Elise. "LATEX HYBRIDES URETHANE/ACRYLIQUE POUR APPLICATIONS ADHESIVES". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2009. http://tel.archives-ouvertes.fr/tel-00465348.
Pełny tekst źródłaWu, Yong Kang. "Biostability/biodegradation of poly(ether urethane)s". Case Western Reserve University School of Graduate Studies / OhioLINK, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=case1061314415.
Pełny tekst źródłaTodd, Jordana Louise. "UV-initiated synthesis of novel urethane polymers". Thesis, University of Central Lancashire, 2007. http://clok.uclan.ac.uk/20200/.
Pełny tekst źródłaHunt, Jason Patrick. "Synthesis and dynamic mechanical studies of a urethane-based polyrotaxane". Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/8553.
Pełny tekst źródłaAlshuiref, Abubaker. "Synthesis and characterization of urethane-acrylate graft copolymers". Thesis, Link to the online version, 2006. http://hdl.handle.net/10019/491.
Pełny tekst źródłaChristenson, Elizabeth. "Biostability and Biocompatibility of Modified Polyurethane Elastomers". Case Western Reserve University School of Graduate Studies / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=case1118268387.
Pełny tekst źródłaAbd, Elrehim Mona Hassan Mohammed. "Synthesis and characterization of hyperbranched poly(urea-urethane)s". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2004. http://nbn-resolving.de/urn:nbn:de:swb:14-1091096011203-44194.
Pełny tekst źródłaKiziltay, Aysel. "Biodegradable Poly(ester-urethane) Scaffolds For Bone Tissue Engineering". Phd thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613811/index.pdf.
Pełny tekst źródłahowever, there are only few applications of amino acid based PUs in tissue engineering. In this study, a biocompatible and biodegradable thermoplastic poly(ester-urethane) (PEU) based on L-lysine diisocyanate (LDI) and polycaprolactone diol (PCL) was synthesized and used for the preparation of two dimensional (2D) films and three dimensional (3D) scaffolds. The resulting polymer was casted as 2D films for full characterization purpose and it was found that it is highly elastic with modulus of elasticity ~12 MPa. Surfaces of 2Ds were modified via micropatterning and fibrinogen coating to check the material-cell interaction. The 3D scaffolds were obtained by salt leaching and rapid prototyping (bioplotting) techniques. The 3D scaffolds had various pore size and porosity with different mechanical strength. The bioplotted scaffolds had uniform pore size of ~450 µ
m and exhibited higher compressive modulus (~4.7 MPa) compared to those obtained by salt leaching (~147 kPa). Salt leached 3D scaffolds had inhomogenous pore size distribution in the range of 5 µ
m - 350 µ
m and demonstrated greatest degradation profile compared to 2D films and 3D bioplotted samples under enzymatic condition. Rat bone marrow stem cells (BMSCs) were used to investigate the biocompatibility of the polymer and suitability of fabricated scaffolds for osteogenesis. Presence of micropatterns on 2D matrices did not show any influence on osteoblastic function, but presence of fibrinogen enhanced cell attachment and proliferation. All of the fabricated 3D PEU matrices supported proliferation, osteoblastic differentiation and extracellular matrix (ECM) deposition with highest osteoblastic activity on bioplotted scaffolds which confirmed by von Kossa staining and EDX analysis. The results indicated that the synthesized PEU based scaffolds were able to induce osteoblastic differentiation and mineralization of BMSC and therefore these scaffolds can be good candidates to be used in bone tissue engineering
Preston, Christopher M. L. "Poly(dimethylsiloxane) : blends with poly(urethane) & radiation chemistry /". [St. Lucia, Qld.], 2000. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16169.pdf.
Pełny tekst źródłaHsu, Tze-Chien Jeffrey. "Urethane-based IPNs and polyureas in reactive polymer processing /". The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487331541711679.
Pełny tekst źródłaLau, Soo-Khim. "The structure-property relationships of urethane-acrylic thermosetting systems". Thesis, Loughborough University, 1995. https://dspace.lboro.ac.uk/2134/27415.
Pełny tekst źródłaWintersgill, S. "Reactions of group IV metal compounds with isocyanates, and their catalytic applications". Thesis, University of Newcastle Upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311171.
Pełny tekst źródłaGibb, Jack Nicholas. "The competing reactions of polyurethane foam formation : a computational and experimental study". Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648568.
Pełny tekst źródłaFallon, Jake Jeffrey. "Structure-Process-Property Relationships of Cellulose Nanocrystal Thermoplastic Urethane Composites". Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/103053.
Pełny tekst źródłaDoctor of Philosophy
Bakhshi, R. "Coating stent materials with polyhedral oligomeric silsesquioxane-poly(carbonateurea)urethane nanocomposites". Thesis, University College London (University of London), 2009. http://discovery.ucl.ac.uk/18987/.
Pełny tekst źródłaHullard, Stephen Mark. "Studies towards siloxane-urethane elastomers for upper extremity prosthesis cosmetic gloves". Thesis, Cardiff University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316357.
Pełny tekst źródłaAnderson, Gabriel Donn. "Long-term Durability Characterization and Prediction of a Urethane-based Adhesive". Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/98825.
Pełny tekst źródłaMaster of Science
Polymeric adhesives play an increasingly critical role in today's engineering designs. When used, adhesively bonded components reduce or eliminate the need for bolted or welded connections, reducing their weight in the process. With adhesives, noise and vibration reduction are possible, as is the use of unique or complicated designs that could not otherwise be constructed. Adhesive properties, however, can vary greatly with time, temperature, and other environmental exposure conditions such as moisture. It is therefore critical to understand the behavior of adhesives over the range of conditions that a bonded component might experience. In this work, the behavior of a urethane-based adhesive was characterized in order to develop long-term durability predictions. Numerous test methods have been developed to characterize the behavior of adhesively bonded joints. In this work, T-peel specimens were used consisting of two aluminum sheets (the adherends), bonded together with tabs bent back in the shape of a "T" for gripping in a universal load frame. During testing, the load required to propagate a crack in the adhesive layer is measured. An outcome of this measurement and subsequent data analysis is the fracture energy—a measure of the effectiveness of the adhesive in transferring loads. If we perform these tests at different temperatures and loading rates, we can determine fracture energy values which span a wide range of possible material behavior. Using principles from basic polymer physics, the collected data can be shifted to different times or temperatures enabling us to accurately predict the behavior of the adhesive over years or even decades. In this work, nearly 200 T-peel samples were tested in four different studies. A preliminary set of unaged specimens was used to develop testing and data analysis methodologies. Unaged and cyclically (temperature) aged samples were tested over a wide range of temperatures and rates. The fourth set of specimens was subjected to 20 separate isothermal aging conditions and also tested at different temperatures and rates. The experimental data showed that the 400+ temperature cycles were insufficient to damage these samples significantly. Additionally, samples aged for up to 2000 hours in a dry environment, or 500 hours in a wet environment showed no reduction in performance in comparison with unaged samples. Specimens aged for more than 500 hours in a wet environment however, demonstrated a significant decreases in fracture energy values. Strong correlations between the thickness of the adhesive layer and estimated fracture energy values were found in this study, and new analysis techniques were developed to analyze the effect of these thickness variations on the joint performance.
Klepáč, Patrik. "Výroba mělkého výtažku pryží". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228146.
Pełny tekst źródłaBass, Roger Wesley. "Synthesis and Characterization of Self-Healing Poly (Carbonate Urethane) Carbon-Nanotube Composites". Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/2999.
Pełny tekst źródłaTipton, Allison Breanne. "An investigation into the imaging properties of semi-rigid urethane casting resin". Thesis, University of Iowa, 2011. https://ir.uiowa.edu/etd/1271.
Pełny tekst źródłaMeng, Lei. "Investigation of non-isocyanate urethane functional latexes and carbon nanofiller/epoxy coatings". University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1445733724.
Pełny tekst źródłaQUINI, JOSUE G. "Adesivos estruturais uretânicos aplicados a combinações de compósitos plásticos e metais". reponame:Repositório Institucional do IPEN, 2011. http://repositorio.ipen.br:8080/xmlui/handle/123456789/9995.
Pełny tekst źródłaMade available in DSpace on 2014-10-09T14:04:04Z (GMT). No. of bitstreams: 0
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
Barnes, Dunstan Henry. "Calcium phosphate coatings on polycarbonate urethane substrates for artificial spinal disc replacement devices". Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608917.
Pełny tekst źródłaO'Sickey, Matthew J. "Characterization of Structure-Property Relationships of Poly(urethane-urea)s for Fiber Applications". Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/26792.
Pełny tekst źródłaPh. D.
Asplund, Basse. "Biodegradable Thermoplastic Elastomers". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-7434.
Pełny tekst źródłaNebipasagil, Ali. "Chemically and Photochemically Crosslinked Networks and Acid-Functionalized Mwcnt Composites". Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/42703.
Pełny tekst źródłaMaster of Science
Cornish, Martyn Christopher. "Role of chemical architecture on the physical properties of model poly(urethane-urea) elastomers". Thesis, University of Manchester, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.705546.
Pełny tekst źródłaBOHN, VERONIQUE. "Contribution a l'etude du carbamate d'ethyle (urethane) dans les eaux de vie de fruits". Strasbourg 1, 1987. http://www.theses.fr/1987STR10771.
Pełny tekst źródłaNishioka, Marcia G. "Identification of Carcinogenic Di-amines in the Indoor Environment from Common Urethane Polymer Products". The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu148344608670484.
Pełny tekst źródłaBorth, David J. "Non-Destructive Evaluation of Urethane-Ester Coating Systems Using the Scanning Kelvin Probe Technique". University of Dayton / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1524749968517527.
Pełny tekst źródłaSasubilli, Ramakrishna Gutheil William G. "Solid-phase synthesis of peptides and peptide mimetics using urethane and backbone amide linker strategies". Diss., UMK access, 2006.
Znajdź pełny tekst źródła"A thesis in pharmaceutical sciences." Typescript. Advisor: William G. Gutheil. Vita. Title from "catalog record" of the print edition Description based on contents viewed Nov. 9, 2007. Includes bibliographical references (leaves 63-73). Online version of the print edition.
Carpenter, Phillip P. "Examination of the surface and interfacial properties of an epoxide-urethane resin for surface coatings". Thesis, Loughborough University, 1997. https://dspace.lboro.ac.uk/2134/32637.
Pełny tekst źródłaIurzhenko, Maksym. "Electrical, thermomechanical and sorption properties of hybrid organic-inorganic systems based on urethane oligomers and silicates". Phd thesis, Université Claude Bernard - Lyon I, 2009. http://tel.archives-ouvertes.fr/tel-00689865.
Pełny tekst źródłaLi, Mei. "Preparation of urethane-acrylic hybrid miniemulsion nanoparticles /". Diss., 2002. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3048964.
Pełny tekst źródłaLin, Yo-Shao, i 林育劭. "Phase Transitions and Morphology Siloxane-Ether Urethane Copolymer". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/19563698741778077006.
Pełny tekst źródła萬能科技大學
工程科技研究所
93
Siloxane-ether urethane (PDMS/PTMG-PUBD) and siloxane-ether-imide urethane (PDMS/PTMG-PUIM) copolymers prepared from a one step method in the N,N-Dimethyformamide(DMF)/tetrahydrofuran(THF) mixed solvent. The soft-segment of PDMS/PTMG-PU copolymers consist of polydimethylsiloxane (PDMS) and polytetramethylene glycol (PTMG) and hard-segment is urethane segment reacting from 1,4-butane diol(1,4-BD) and 4,4-diphenylmethane diisocyanate(MDI). The soft segment of PDMS/PTMG-PUIM was similar to PDMS/PTMG-PUBD but hard-segment is a imide segment consisting of 3,3', 4,4'-Diphenylsulfone-tetracarboxylic Dianhydride(DSDA) and MDI. The phase-separation degree of copolymers was lower than that the non-polar PDMS polyurethane because the copolymers incorporated PTMG in the soft-segment to increased the miscibility between soft segment and hard segment. The PDMS/PTMG-PUBD and PDMS/PTMG-PUIM in the differential scanning calorimeter (DSC) exhibited soft- and hard-segmented phase-transition. The soft-segmented phase-transition PDMS/PTMG-PUBD and PDMS/PTMG-PUIM including the PDMS and PTMG amorphous phase-transition but the crystal phase-transition only presented on the melting-quenched PDMS/PTMG-PUIM copolymers. There were two endothermal regions, which were respectively the short-range ordering and the long-range ordering of hard segment domains(Region I and II), displaying at around 100℃ and 160℃. The endothermic behavior was demonstrated by annealing measurement displaying was a enthalpy relaxation resulting from prolonged physical aging. Furthermore, the hard-segmented crystal (Region III) appeared on the high hard-segment content of PDMS/PTMG-PUBD sample annealing for a period.
Chiu, Hsien-Chang, i 邱憲章. "Thermal Degradation Characteristics of Siloxane-Ether Urethane Copolymer". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/36760374872465685986.
Pełny tekst źródła萬能科技大學
工程科技研究所
94
Siloxane-ether urethane (PDMS/PTMG-PU) and siloxane-ether-imide urethane (PDMS/PTMG-PUIM) copolymers were synthesized in this study. The hard segments consisted of 4,4-diphenylmethane diisocyanate (MDI) and 1,4-butane diol (1,4-BD) or MDI and 3,3’,4,4’-diphenylsulfone tetracarboxylic dianhydride (DSDA). The soft segments were mixture of poly(tetramethylene glycol) (PTMG) and polydimethylsiloxane diol (PDMS). TGA measurement indicated that the degradations of copolymers were obviously distinguished into two stages. The degradation in the first stage was the decomposition of urethane hard segments. The urethane segments were composed of urethane-B (MDI and 1,4-BD ), urethane-S (MDI and PDMS) and urethane-G (MDI and PTMG) due to the various structures. The TG and DTG curves showed individual degradation region of these urethane segments. They also presented various activation energies calculated by Ozawa method. The degradation in the second stage was breakdown of PDMS and PTMG soft segments. The degradation of two soft segments was unable to discriminate absolutely due to the mixing ratios of PDMS and PTMG. The degradation of PDMS produced cyclics by interaction of siloxane bonds. The interactions among cylics formed macrocyclics. The degradation of copolymers with high PDMS content in the range of high temperature emerged the degradation behavior of macrocyclics. TG-IR analysis exhibited that the degradation of PDMS/PTMG-PU copolymer were along the sequences of urethane-B and urethane-G, PTMG and PDMS, macrocyclics. These for PDMS/PTMG-PUIM copolymer were urethane-G, imide, PTMG and PDMS, macrocyclics.
Cheng, Wei-Yuan, i 鄭磑元. "Study of Aliphatic Urethane Acrylate UV-curing Coatings". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/b38ybp.
Pełny tekst źródła國立臺北科技大學
有機高分子研究所
105
This purpose is discussed the physical properties of the radical light-cured coating performance on ABS materials. Use with different acrylic monomers and acrylic resin light curable coatings reach on the physical properties of ABS materials adhesion, hardness, abrasion more improved. Radical curing system having acrylic group 1,6-Hexanediol Diacrylate(HDDA)、Dipentaerythritol Hexaacrylate(DPHA), added photoinitiator (1-hydroxycyclohexyl phenyl ketone) and leveling agent(Polyether modified silicone), and is to 600mj/cm2 of UV light energy. Cross hatch test paint adhesion on ABS materials, In pencil hardness meter test paint on ABS materials, In RCA abrasion meter test paint on ABS materials, In Fourier transform infrared spectrometer (FTIR) to test for different coating composition, In Dynamic Mechanical Analysis (DMA) to test Glass Transfer Temperature (Tg), In Thermogravimeteric Analysis (TGA) to test Degraded Temperature (Td), With a variety of match to reach the photo curable coating properties can be improved. As test results, DPHA were improved properties of hardness and abrasion obviously.
Jang, Shin-Cheng, i 張欣程. "Synthesis and Physical Properties of Siloxane-Urethane Copolymer". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/22519219672495032590.
Pełny tekst źródła逢甲大學
紡織工程所
96
Siloxane-urethane copolymers and siloxane-urethane-imide copolymers were synthesized by one-step process. Siloxane-urethane copolymers prepared from polydimethylsiloxane diol (PDMS) with a molecular weight 1000 or 1800 which was used as a soft segment, 4,4''-diphenylmethane diisocyanate (MDI) and 1,4-butanediol (1,4-BD). Siloxane-urethane-imide copolymers prepared from PDMS with a molecular weight 1000 or 1800, MDI and pyromellitic dianhydride (PMDA). The hard segment of conventional polyurethane displayed one stage of degradation. Siloxane-urethane copolymers exhibited two types of urethane hard segments (urethane 1 and urethane 2). Urethane 1 consisted of MDI and 1,4-BD. Urethane 2 consisted of MDI and PDMS. The characteristics of degradation in the urethane hard segments demonstrated by TGA analysis and Ozawa method presented two types of temperature. Therefore, urethane hard segments of siloxane-urethane-imide copolymers were urethane 2. Their characteristics temperature of degradation in the first stage increased with the imide group contents. The degradation temperature of PDMS soft segment was higher than hard segment and the maximum temperature occurred at 480 °C. Furthermore, a cyclosiloxane of decomposition produce resulted from thermal decomposition of PDMS at the temperature, and subsequently produced macrocyclics beyond 480 °C. The siloxane-urethane-imide copolymers exhibited the degradation in the third stage. This degradation was the decomposition of imide group. The initial temperatures of degradation in the third stage were constant at various imide group contents. However, these maximum temperatures of degradation increased with the increasing in the imide group contents. Differential scanning of calorimetry (DSC) demonstrated that the position (Tgs) and breadth (ΔB) of soft-segment glass transition of siloxane-urethane copolymers remained constant as the hard-segment contents increased. Heat capacities at soft segment glass transition of copolymer (ΔCp) changed with the various hard and soft segment contents, leading to the various ΔCp/ΔCp0 ratios. The various heat capacities were attributed to the polar ether end-group of PDMS prepolymer. The result confirmed that the ether end-group of the soft segment led to interfacial mixing between soft and hard segments. The tanδ of the soft segment determined by dynamic mechanical testing (DMA) also identified the mixing of soft and hard segment. The Tgs and ΔB of soft-segment glass transition of siloxane-urethane-imide copolymers raised as the hard-segment contents increased. The ΔCp/ΔCp0 ratios were consistent with the Tg and �婿 shown. These results demonstrated the copolymers with higher imide group contents displayed less phase separation. The thermal behavior of amorphous hard segment for the copolymer with 62.3 % hard-segment content was studied by differential scanning calorimetry (DSC). Upon annealing at 100 °C, both the T1 temperature and magnitude of the T1 endotherm increased linearly with the increase in logarithmic annealing time. This phenomenon was typical of enthalpy relaxation resulting from the physical aging of amorphous hard segment. Upon annealing above 100 °C, the T1 endotherm shifted to high temperature until its merger with the T2 endothermic temperature. The T2 multiple endotherm appeared between 180 °C and 240 °C at 170 °C annealing temperature and its magnitude increased with the annealing time, indicating that the increase of range order.
Tzeng, Shr-Gung, i 曾士恭. "Studies on UV-curable Poly(urethane acrylate) Resin". Thesis, 2004. http://ndltd.ncl.edu.tw/handle/93735945589867174545.
Pełny tekst źródła國立臺灣大學
化學工程學研究所
92
UV curable polyurethane acrylate resins based on polyoxypropylene glycol(PPG) soft segment with different molecular weights were synthesized in this study. The kinetics of UV curing under different UV exposure doses, at various photoinitiator concentration was investigated and the kinetic equation was derived. In addition, UV curable urethane-acrylate resins were considered as reactive acrylate monomers as reactive diluents: Tripropylene Glycol Diacrylate(TPGDA) and Acrylic acid(AA). Further more, physical properties of this type of UV curable material, the effects on properties by varying the molecular weight of PPG and the effect of using various reactive diluents were discussed. The internal reference peak of acrylate group(=C-H Out-of-plane bending,990cm-1) was methyl group (CH3 bending~1375cm-1). The peak changes were tracked with FTIR. The results reveal that the kinetic rate equation for the concentration of acrylate group which UV exposure is first order, and for UV exposure dose is one-half order, and the UV exposure relationships is proportional to (1-exp(-2.303ε[PI]d))0.5. The tensile strength and elongation at break of UV curable films increased with increase of AA concentration .The thermal decomposition temperature of UV curable films decreased with increase of AA concentration .The glass transition temperature(Tg) of UV curable films shifted to a higher temperature as the content of AA increased .This was interpreted in terms of possible compatibility of urethane hard segments and carboxylic acid group of AA due to their similar polarity and hydrogen bonding. In the adhesion test, it reveals that resin with increase of AA concentration show higher adhesion to the PET film.
Lin, Shih Jyun, i 林士君. "Synthesis and Characterizations of New Poly(urethane-amine)Dendrimer". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/60691526534778373735.
Pełny tekst źródła嘉南藥理科技大學
生物科技系
101
The aim of this study is preparation of polyurethane dendrimers (PUAD-EIA, PUAD-OH,PUAD-NH2) by divergent method.The chemical structure of the dendrimer was indentified by fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR).To evaluate their physical and chemical properties, we executed a series of experiments. The particles size was characterized by transmission electron microscopy (TEM). Zeta-potential analyzer was also performed to understand surface properties of polymer. Acid-base titration studies was performed to determine the buffering capacities.The MTT assay was used to assess the cytotoxicity of polymers, in addition, observed the hydrolysis ability and analysis of drug solubility. We found that the synthesized dendritic polymer is biodegradable, nano-sized,and can increase the solubility of poorly water-soluble drugs. From above data, polyurethane dendrimers can be used as an ideal gene and drug delivery system.
Chen, Yen-Jung, i 陳妍蓉. "Novel Urethane-acrylate Root Canal Sealer:Cytotoxicity and Antibacterial Effect". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/20050485394139068873.
Pełny tekst źródła國立臺灣大學
臨床牙醫學研究所
99
For sealing off of the root canal system after completely cleaning and shaping, the standard root canal filling is a combination of sealers with gutta-percha cone. The ideal root canal sealer needs good biocompatibility and antibacterial effect. Our research team has developed dual-cured urethane-acrylate (UA) sealer. Theses materials have good handling characteristics and bonding strength. For further research about the safety of urethane-acrylate sealer. The purposes of this study were to investigate the cytotoxicity and antibacterial effect of UA sealer. The results showed the PC-based UA sealer and Apexit have lower cytotoxicity than PBA-based UA sealer and commercial products such as Endorez, AHplus and Tubliseal. In antibacterial effect test, AHplus has higher antibacterial effect and UA sealers have lower antibacterial effect than other commercial products. We conclude that the cytotoxicity and antibacterial effect have correlations, and the higher bactericide effect may also kill the normal cell. PC-based UA sealer with higher conversion rate and good biocompatibility has high potential for clinical use.
WANG, HSING-LUNG, i 王興龍. "Study on Polyether Poly(urethane-urea) as Polymer Electrolyte". Thesis, 2000. http://ndltd.ncl.edu.tw/handle/95147117805778380880.
Pełny tekst źródła國立成功大學
化學工程學系
88
The behaviors of lithium ions in a polyether poly(urethane urea) (PEUU) were investigated by Differential Scanning Calorimetry (DSC), Fourier Transform Infra-Red (FTIR) spectroscopy, AC Impedance and magic angle spinning (MAS) solid state NMR measurements. The PEUU, used in this study, is composed of polyethylene glycol (PEG, mol. wt. 1000) as the soft segment and 4,4’-methylene bis(cyclohexyl isocyanate) extened with ethylene diamine (EDA) as hard segment. DSC experiments indicate the formation of transient cross links between Li+ ions and the ether oxygens on complexation with LiClO4, resulting in an increase in soft segment Tg. From the FTIR study, an appreciable change in the free as well as both of the hydrogen bonded —NH stretching bands has been observed, which suggests possible interactions of Li+ ions with both hard and soft segments of PEUU. The Arrhenius-like behavior of AC conductivity with reciprocal temperature suggests an activated hopping mechanism for transport of the charge carriers where the charge-carriers are decoupled from the segmental motion of the polymer chains. Significant line broadening, slight upfield chemical shift and short TCH, observed in the 13C NMR spectra for the carbons attached to the ether oxygens as the dopant was added into the polymer, indicates that a coordination between the Li cation and the ether oxygens in the soft segments. A systematic modeling analysis for composite electrolytes prepared by impregnating the ternary composites consisting polyethylene glycol based poly(urethane-urea) (denoted as PEUU(PEG)), polytetramethylene glycol based poly(urethane-urea) (PEUU(PTMG)), and polyethylene oxide (PEO) with LiClO4-PC. The results of swollen weight and conductivity at ambient temperature for composite electrolytes were fitted as empirical regression equations by using mixture design. These empirical equations were plotted as contour diagrams. The results indicates the composite electrolytes showed appropriate conductivities (liquid-like)only when swollen weight were over than 25 %.
Lin, Mai-Jane, i 林美珍. "Mechanistic Studies of Rhenium Complexes Catalyzed Urethane Formation Reaction". Thesis, 1995. http://ndltd.ncl.edu.tw/handle/00601543321349084470.
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