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El presente trabajo es una contribución para dar a conocer a un nuevo sistema no convencional "Royal Building System" o RBS la traducción literal no es muy precisa en el sentido que se le quiere dar a la denominación del sistema, no es un sistema de construcción real sino un sistema de construcción que usaría la realeza en el mas amplio sentido del marketing. Esta tesis pretende analizar los componentes de los Sistemas convencionales y no convencionales, para la fabricación de ambientes, de características similares y las correspondientes normas aplicables.

The suspension polymerisation of vinyl chloride is the main industrial process used for the production of PVC. One of the key operations in this process is liquid-liquid agitation. The stability of the dispersion formed by such a system depends upon a number of parameters that have to be controlled. The present study clarifies drop behaviour in dispersion of vinyl chloride monomer, using poly(vinyl alcohol) stabilisers, before and during polymerisation. In order to carry out our experiments, a11. capacity pressurised reactor system connected to an external microscopic optical cell was designed along with a reflux system. Parameters affecting the initial VCM dispersion, prior to suspension polymerisation, such as residence time, agitation speed, volume fraction and type and concentration of suspending agent have been studied in some details and a correlation relating the Sauter mean diameter (D32) to the vessel geometry, the volume fraction and the Weber number has been proposed. Studies of drop coalescence using a tracer ( dye ) under different experimental conditions showed that the rate of coalescence between non-polymerising VCM droplets was relatively slow, proportional to the agitator speed and decreased by increasing PVA concentration. The PVA adsorption on VCM droplets during both dispersion and polymerisation was also studied. It was found that during polymerisation the rate of adsorption was relatively high at the early stages. The individual mechanisms of the droplets formation and subsequent droplet agglomeration processes in suspension polymerisation were also investigated. It was found that the method of addition of initiator was very important as it affects the morphology as well as the conversion of the final product. The influence of the condenser operation in the suspension polymerisation of vinyl chloride and its effects on the mechanism of droplet formation were also studied and the fate of monomer droplets returning from the condenser were investigated. The external morphology of the final PVC particles was studied using scanning electron microscopy (SEM) technique.

Diss. (sammanfattning) Linköping : Linköpings universitet, 2007. / Härtill 5 uppsatser.

A low molecular weight fraction was obtained from a mass polymerised PVC resin by using diethyl ether Soxhlet extraction followed by either preparative gel filtration or solvent fractionation. A gas chromatography - mass spectroscopy (GC-MS) analysis of this fraction revealed that, in addition to vinyl chloride (VC) oligomers, it contained a large number of other compounds, in particular a large concentration of phthalates. By using adsorption liquid chromatography it was possible to remove the phthalates, along with other contaminants having a similar or greater polarity, from the low molecular weight PVC fraction.

Free-radical solution polymerization techniques have been used to prepare carboxyl-terminated poly(methyl methacrylate) and poly(2- ethyl hexyl acrylate) homopolymers. The molar masses of these prepolymers were readily controlled and they were found to be approximately monofunctional with respect to carboxy I groups. These carboxyl-terminated prepolymers were converted to methacrylate-terminated macromonomers via acyl chlorideterminated intermediates. The macromonomer functionalities obtained by this procedure were high, typically 0.90-1.05 methacrylate groups per molecule on average. The prepolymers and macromonomers were characterized using End-group analysis (EGA). Infra-red spectroscopy (IR), 1H Nuclear Magnetic Resonance spectroscopy (lH NMR) and Gel-permeation Chromatography (GPC). Polystyrene-graft-poly(methyl methacrylate) and polystyrene-graft-poly(2-ethyl hexyl acrylate) copolymers were prepared by the free-radical solution copolymerization of macromonomers (M2) with styrene (M1). A dual detector GPC method was used to estimate macromonomer conversions. Unreacted macromonomer and styrene were removed and the purified graft copolymers were characterized by Thin-layer Chromatography (TLC) , GPC, IR and 1H NMR. It was shown that efficient grafting had occurred by copolymerization of the macromonomer end-group and that ungrafted polystyrene backbone was not produced. The graft copolymer chemical compositions and physical architectures were controlled by changing the comonomer feed composition or the macromonomer molar mass. Reactivity ratios (r1) were determined by the Jaacks, Finnemann-Ross and Kelen-TUdos methods. It was shown that the reactivities of the methacrylate-terminated macromonomers were approximately similar to conventional methacrylates and independent of the macromonomer molar mass or composition within the limits investigated. The polystyrene-graft-poly(2-ethyl hexyl acrylate) copolymers have been used as stabilizers in the free-radical non-aqueous dispersion polymerization of methyl methacrylate in aliphatic hydrocarbons. The poly(methyl methacrylate) particles were characterized by Transmission Electron Microscopy (TEM) in order to determine their size, shape and state of aggregation. Ultraviolet spectroscopy (UV) was used to determine the graft copolymer content of the particles, from which an estimate of surface coverage was made. The effects of varying the polymerization method, and both the composition and concentration of stabilizers used, were studied. The average particle size, particle size distribution and the state of aggregation were found to be dependent upon these parameters.

Green reinforcement in polymer systems have shown great promise in reducing cost, negative environmental effects, and dependency on nonrenewable resources. Both natural fillers and composite regrind can increase mechanical performance, while reducing new resin inputs for polymer based components. PVC and Polyurethane foam are widely used in North America in high volumes. Ground corn cob greatly increased the modulus of a flexible PVC system while minimally reducing maximum strength. The corn cob also showed signs of being a suitable filler in a polyurethane foam composite panel at low concentrations with minimal changes in mechanical performance. Polyurethane composite regrind illustrated great potential being used in new polyurethane composite panels with acceptable material properties. Replacing just a few percent of polyurethane and PVC with green reinforcement could reduce new production of these polymers by millions of pounds per year in North America alone.

Indiana University-Purdue University Indianapolis (IUPUI) / A Polyvinylchloride surface was modified by coating a biocompatible, hydrophilic and antibacterial polymer by a mild surface modification method. The surface was first activated and then functionalized, followed by coating with polymer. The surface functionality was evaluated using cell adhesion, bacterial adhesion and bacterial viability for polymers with antibacterial properties. 3T3 mouse fibroblast cells were used for cell adhesion, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus were used for bacterial adhesion in the first study, Pseudomonas aeruginosa and Staphylococcus aureus were used for bacterial adhesion and antibacterial activity in the second study. Chapter 2 reports how we synthesized, immobilized and evaluated a novel hydrophilic polymer with anti-fouling properties onto surface of polyvinylchloride via an effective and mild surface coating technique. The polyvinylchloride surface was first activated by azidation as well as amination, and then tethering a newly synthesized hydrophilic and biocompatible polyvinylpyrrolidone having pendent reactive succinimide functionality onto the surface. Results show that the coated hydrophilic polymer significantly reduced the 3T3 fibroblast cell adhesion as well as the adhesion of the three bacterial species. Chapter 3 reports how we prepared, immobilized and evaluated an antibacterial and anti-fouling polymer onto polyvinylchloride surface following an efficient and simple method of surface modification. The surface coated with a terpolymer constructed with N-vinylpyrrolidone, 3,4-Dichloro-5-hydroxy-2(5H)-furanone derivative and succinimide residue was evaluated with cell adhesion, bacterial adhesion and bacterial viability. Surface adhesion was evaluated with 3T3 mouse fibroblast cells and two bacterial species. Also, antibacterial activity was evaluated by bacterial viability assay with the two bacterial species. Results showed that the polymer-modified polyvinylchloride surface exhibited significantly decreased 3T3 fibroblast cell adhesion and bacterial adhesion. Furthermore, the modified polyvinylchloride surfaces exhibited significant antibacterial functions by inhibiting bacterial growth with bactericidal activity. Altogether, we have successfully modified the surface of polyvinylchloride using a novel efficient and mild surface coating technique. The first hydrophilic polymer-coated polyvinylchloride surface significantly reduced cell adhesion as well as adhesion of three bacterial species. The second hydrophilic and antibacterial polymer-coated polyvinylchloride surface demonstrated significant antibacterial functions by inhibiting bacterial growth and killing bacteria in addition to significantly reduced 3T3 fibroblasts and bacterial adhesions.

As blendas poliméricas são importante alternativa ao mercado para se conseguir de forma economicamente vantajosa ou sob o ponto de vista de processabilidade produtos com propriedades otimizadas para aplicações específicas. Blendas com razões de composição variadas entre diferentes polímeros atendem aplicações muitas vezes com requisitos intermediários entre materiais. Este trabalho revisa sucintamente a literatura sobre blendas poliméricas, a produção em laboratório de uma blenda mecânica de poli(cloreto de vinila) PVC e poli(metacrilato de metila) - PMMA, avalia as propriedades de blendas com frações variadas de PVC/PMMA e discute o potencial de aplicação no mercado. A blenda miscível caracterizada tem custo, resistência à chama e propriedades mecânicas e térmicas intermediárias aos dois polímeros puros. / Polymer blends are an important alternative in the market for achieving, in an economically and advantageous way or just considering processability products with optimized properties for specific applications. Blends with variable composition ratios, between two different polymers, fit to applications with intermediate requirements between two different materials. This paper reviews slightly the literature about polymer blends, the lab scale production of a mechanical blend of poli(vinylene vhloride) - PVC and poly(methyl metacrylate) - PMMA with different PVC/PMMA ratios and the application potential. The miscible blend shows intermediate cost, flame resistance, mechanical and thermal properties then those shown by its neat polymers.