L'objectif de ce travail est d'étudier la faisabilité d'ajout de sel nylon à un polyamide (PA) par un procédé d’extrusion réactive. Dans ce cadre, l'ajout de sel 6T comprenant des motifs aromatiques à du PA 66 est réalisé dans le but de synthétiser du PA 66/6T. En effet, ce dernier répond à la demande actuelle en polymères à haute résistance thermique. Le taux d'avancement de la réaction et le taux de motifs 6T insérés doivent dès lors être maximisés.Le travail comprend les synthèses et les analyses du sel 6T, du PA 6T et du PA 66/6T. Le sel 6T est produit puisqu'il n'est pas commercialisé. Le PA 6T est synthétisé pour permettre l’identification des hydrogènes aromatiques du PA 66/6T. Le travail sur ce dernier nécessite la mise au point et l'étude du procédé d'extrusion. Pour ce faire, les influences d'un certain nombre de paramètres opératoires sont étudiées comme, par exemple, le niveau de vide sur les évents de l'extrudeuse.Les meilleures conditions opératoires du procédé permettent d’obtenir un taux d'avancement de 93 mol% et un taux d'insertion de motifs 6T de 15,3 mol%. Néanmoins, le PA 66/6T produit présente un fort excès de fonctions terminales acides / The aim of this work is to study the feasibility of addition of nylon salt to polyamide (PA) by a reactive extrusion process. As example, the addition of 6T salt, which includes aromatic monomers, to PA 66 is performed in order to synthesize PA 66/6T. This latter replies to demand of high resistance temperature polymer. Consequently, the progress rate of the reaction and the rate of 6T motifs insertion have to be maximized.This work includes the synthesis and the analysis of 6T salt, PA 6T and PA 66/6T. 6T salt synthesis is performed since it is not commercialised. PA 6T is synthesized in order to identify aromatic hydrogen in PA 66/6T molecule. About this latter, it is necessary to adjust and to study the extrusion process. So, the influences of few process parameters are studied as, for example, pressure level on vent gas of the extruder.With the best process parameters, the progress rate is 93 mol% and the rate of 6T motifs insertion is 15,3 mol%. Yet, PA 66/6T presents a significant excess of acidic end group

Made available in DSpace on 2016-04-18T21:35:58Z (GMT). No. of bitstreams: 2 Marcela Nakashima1.pdf: 1850822 bytes, checksum: 69c5b87f6956346c1ed15ad9ab1b6e1d (MD5) Marcela Nakashima2.pdf: 2687336 bytes, checksum: 5bd7fea84f09339364cda3948f2b8e27 (MD5) Previous issue date: 2009-02-13 / This work is about a nanocomposite compound made with a ceramic material and a polymer used as matrix. The purpose of this work is evaluating the influence of the addition of the nanoparticles of the ceramic material in the nanocomposite. The ceramic material used was pseudoboehmite obtained by sol-gel process The pseudoboehmite was obtained from aluminum nitrate and ammonium hydroxide using poly-vinyl alcohol during the precipitation. The polymer nylon 6,12 has used in this process. Mechanical properties also will be analyzed: tensile strength, compression strength, impact thoughness, melt flow, SHORE hardness and density. The results has showed that increased values of the mechanical properties, was compared with the material without adding nanoparticles. / O presente trabalho trata-se do estudo de um nanocompósito à base de cerâmica (fase dispersa) + polímero (matriz), que tem como objetivo de analisar as propriedades mecânicas nanocompósito em relação às propriedades mecânicas do mesmo polímero sem a adição das nanopartículas de material cerâmico. As nanopartículas utilizadas foram de pseudoboemita, obtida pelo processo sol-gel. Na obtenção da pseudoboemita utilizou-se nitrato de alumínio como precursor e hidróxido de amônio com a adição de álcool polivinílico durante a precipitação. A matriz polimérica utilizada foi o nylon 6,12. As propriedades mecânicas avaliadas foram: resistência à tração, resistência a compressão e resistência ao impacto, índice de fluidez, dureza SHORE e densidade. Os resultados mostram que houve um aumento nos valores de propriedades mecânicas do material obtido em relação ao polímero sem adição de nanopartículas.

The catalytic depolymerization/pyrolysis of nylon 6 and 66 were investigated with the prospect of helping to curb the amount of carpet landfilled. Thermogravimetric analysis was used to determine which catalysts (and their nylon/catalyst ratio) were most suited for the depolymerization. By adding bases, the onset of degradation for some bases was 100 aC lower than that of the pure nylons. Potassium hydroxide and sodium hydroxide were found to be the most effective catalysts at a catalyst ratio of 100:1 of nylon 6 and nylon 66 to catalyst, respectively. After determining the most efficient catalyst, kinetic models/parameters from the TGA data were determined. These parameters were used in a reactive extrusion model for depolymerizing nylon 6 in carpet. Data from the model was then used to do cost analysis for the process. It was found that to get a Present Value Ratio greater than 1, the flow rate has to be greater than or equal to 500 lb/hr. At even higher flow rates up to the model¡¦s limit (1500 lb/hr), the Net Present Value shows that this process is economically viable. Extrusion of a 100:1 ratio of pure N6 and KOH was done in a 30 mm counter-rotating non-intermeshing twin screw extruder. The material collected from the vents of the extruder was tested with a gas chromatograph- mass spectrum (GC-MS) in tandem. There was only one significant peak from the GC and the primary molecular weight on the MS was 113, the molecular weight of caprolactam. This shows that the process could be profitable and require little purification if done industrially.

Call number: LD2668 .T4 1985 P68 / Master of Science

Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1982. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING / Includes bibliographical references. / by John Hainsworth. / B.S.

Polymer materials stand on a very significant position in the materials industry area. The presence of organoclay nanocomposites reinforces polymer materials on many properties like strength, tensile and so on. Most previous studies on the characteristics of organoclays and polymer nanocomposites were based on the experimental approaches such as XRD (X-ray Diffraction) and NMR (Nuclear Magnetic Resonance). These methods have achieved successfully on the basic analysis of chains and layering structures of polymer nanocomposites. However, information on the molecular level cannot be provided by those approaches. MD (Molecular Dynamic) simulation method could be employed to develop further information on the molecular level about organoclays and interlayer structure polymer nanocomposites. In the research of ODTMA-MMT (Octadecyltrimethylammonium-Montmorillonite) organoclay simulation, we find that the strong layering behaviour of interlayer ODTMA molecules is present with the same minimum distance between nitrogen atoms and MMT surface in different T/O (Tetrahedral vs. Octahedral) ratio cases. Nitrogen atoms sit right above the corresponding hexagonal cavities, which is in agreement with the previous research. The interaction energy between surfactants and MMT clay will reach the lowest point when substitution ratio of tetrahedral and octahedral (T/O) is equal to 1:1. Moreover, MSD (Mean Square Displacement) and diffusion coefficient of different models under same CEC (Charge Exchange Capacity) condition are inverse ratio to the T/O proportion. In nylon6 polymer nanocomposites, sodium cations which exist originally in ensemble as charge balancer are absorbed much closer to MMT surface than the organic components in the nylon 6 ODTMA-MMT ensemble. Sodium atoms or nitrogen atoms in surfactants both have higher MSD and coefficients than those atoms in the organic-modified clays. In the exfoliated nylon 6 ODTMA-MMT nanocomposites, pair correlation has been analysed instead of density profile. Layering packing structure is also shown through this analysis, which is also consistent with previous work.

Se han sintetizado nylons 1,n (n=5,6,7,8,10 y 12); nylons 2/n estadísticos con distintas proporciones de glicina (n=6, 11 y 12) y nylons m,n (m=6,12; n=6) con glicina incorporada secuencialmente y al azar. Los productos se han caracterizado por los métodos fisicoquímicos habituales y se han estudiado estructuralmente por difracción de rayos x, microscopia electrónica y refino mediante la metodología Lals. Se proponen estructuras cristalinas diferentes de las convencionales derivadas de las preferencias conformacionales del grupo metileno aislado entre grupos amida. La introducción de baja proporción de glicina en los nylons n y m,n con elevado numero de metilenos, da lugar a polímeros que pueden procesarse en forma de fibras con aceptables propiedades mecánicas y buenas posibilidades como materiales biomédicos.

Conductive and flexible nanocomposites can have wide applications in textiles, including wearable sensors, antenna, electrodes, etc. The objective of this research is to develop electrically conductive fibers and films that are flexible and deformable for use in textile structures able to accommodate the drape and movement of the human body. To achieve this objective, we evaluate the electrical properties of PEDOT:PSS/nickel nanostrand as well as nylon 6/nickel nanostrand nanocomposites. Nickel nanostrands (NiNS) were first used to reinforce an intrinsically conductive polymer, Poly(3,4-ethylenedioxythiophene) (PEDOT:PSS), in order to fabricate nanocomposite films with high electrical conductivity. The electrical properties of the films were evaluated by the Van der Pauw method. The addition of 10 wt% nanostrands in PDOT:PSS provided a two order of magnitude improvement in electrical conductivity. In addition to PDOT:PSS, nylon 6/NiNS nanocomposite fibers were produced using electrospinning and exhibited diameters in the sub-micron range. The NiNS-reinforced fibers had electrical conductivity that exceeded the ESD range, which offers the potential for use in protective textile applications. / text

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