MODIFICATION OF MACROMOLECULES

Author: RIBERA LLONC GEMMA.
Year: 2004.
University: ROVIRA I VIRGILI [www.urv.cat].
Place of defense: FACULTAT DE QUÍMICA.
Place of preparation: FACULTAT DE QUÍMICA.

Summary: The organophosphorus compounds have proved to be good to flame retardants for materials with a high oxygen content, such as epoxy resins, in addition to generating less toxic fumes and smoke that halogenated compounds. It has been described as the introduction of phosphine oxide, both in the chain of epoxy resin as in the agemte cure, gives good properties to flame retardants and acting through a mechanism intumescencia, forming an insulating layer that is a physical barrier and ténnica to combustion. The objectives of this work are the synthesis and intersecting new epoxy resins fosforadas, and the study of mechanical properties, ténnicas and retardancia the flame. One way of obtaining epoxy resins fosforadas was the synthesis of derivatives prepolymers oxide isobutyl a (hidroxipropà ¼) phosphine (IHPO) And diglicidil ether of Bisphenol A (DGEBA) or IHPO and 1,6-hexildiglicidiléter (HEDGE), however in this case as they reacted occurred in the homopolimerización of prepolímero training. Attempts were also made to the reaction of phosphonate of dietil-N, N-bis (2-hidroxietil) aminometilo (Fyrol 6) with DGEBA or epiclorohidrina (CLD), but not the desired product was obtained in either case. An alternative is a synthesis of diglicidilos phosphorus by 10que was reacting IHPO with CLD amid core and preséncia of a phase transfer catalyst. This new diglicidilo, IHPOGly, experience and isomerization reactions of decomposition at high temperatures, 10 which requires the use of a catalyst that lowers the temperature of the reaction homopolimerización. Another way of introducing phosphorus in the epoxy resin is cured monomers diglicidilicos agents cured phosphorus. For this reason a synthesized two amines, the oxide of a (maminofenil) metilfosfina (BAMPO) and a diamina derived from the DOPO (2DOPO-A), which contains two molecules DOro in its structure. It is also synthesized oxide P-diamidafenilfosfina (DAPPO), which was not included in the study of the reactions of cured with glicidilos because it gave low grades intersecting in all cases. Once obtained the phosphorus was studied reaction curing DGEBA five amines primárias (hexametilendiamina, 1,2-diaminotolueno (DAT), Diaminodiphenylmethane (DBM), BAMPO and 2DOPO-A) and compared with results obtained from cured the IHPO-Gly and HEDGE with these five amines. The survey shows that there are no significant differences in the chemical structure of glicidilos since obtained similar results in all cases. Also, study the reaction of cured with DAT and DBM, mixtures of IHPO-Gly with DGEBA or HEDGE so that there would be a 1, 3, 5, or 7% of phosphorus in the final resin. In systems IHPO-Gly/HEDGE noted an increase in Tg to increase the percentage of phosphorus, while in systems IHPOGly / DGEBA affects more aromatic structure on the group Tg P = O. Using the technique of DMTA we could observe the Tg materials obtained, as well as a relaxation -50 ° C caused by segments of the rings oxiránicos open. By thermogravimetric analysis (TGA) was able to establish that the presence of phosphorus inhibits the oxidative degradation of the rest carbonado obtained at high temperatures in oxidizing atmosphere, causing the formation of a waste intumescente that protects the material of the fire. Finally, by applying the test UL-94 burning vertically, all materials obtained were classified as V-0.

Author: SÁNCHEZ SÁNCHEZ MARÍA DOLORES.
Year: 2005.
University: COMPLUTENSE DE MADRID [www.ucm.es].
Place of defense: FACULTAD DE CIENCIAS QUÍMICAS.
Place of preparation: FACULTAD DE CIENCIAS QUÍMICAS.

Summary: In this thesis explores information between graft copolymers of polypropylene atáctico, a-PP and each of the homopolymers matrix elected: HDPE, HDPE, low, LDPE and polypropylene isotáctico, i-PP, using as an indicator radical Dicumyl peroxide, attributed to a process of quimisorción extent of the reactions of graft chains on polyolefin. The homopolymers matrix selected prove to be major components (increased 90%) of the fractions of plastic materials in the municipal solid waste streams, while the polypropylene atáctico used as co-reactivo macromolecular reactor is a byproduct of industrial polymerization estereoespecífica of olefins. Characterization techniques used to assess the structural and morphological changes experienced by the original polyolefins them react a-PP in the presence of peroxide have been selective dissolution in various solvents, espectroscopís Infrared Fourier Transform, differential scanning calorimetry, reometría torque and accelerated aging techniques using UV-Vis irradiation. Based on the results obtained and by applying statistical tools has been able to complete the formation of such graft copolymers and that the optimal conditions for it are in the environment of 6.5% by weight concentration a-PP and 2.1% by weight concentration of peroxide.

Author: SANCHIS GISBERT MARÍA ROSA.
Year: 2006.
University: POLITÉCNICA DE VALENCIA [www.upv.es].
Place of defense: Dep. Ingenieria Textil y Papelera.
Place of preparation: Universidad Politécnica de Valencia.

Summary: In recent years there has been a significant growth in the use of polymeric films in technical applications because of the excellent combination of properties such as offering easy processing, versatility in the surface finishes, excellent performance barrier and a good balance of properties (mechanical , thermal, electrical ...). All this has contributed to a massive use of polymers in applications of high technology content in the form of film (packaging, automotive and aerospace, electrical and electronic equipment, medical sector ...). Some films have good adhesive properties, but the most common situation is that bad submit adhesive properties because they have low surface energy values are inert and very smooth surface. Therefore, polymeric films need, in most cases, some additional treatment to improve the surface activity to improve in this way humectabilidad and, consequently, the adhesive properties. In this paper, has been used by low-pressure plasma discharge luminescent with different gases (O2 and N2) to improve humectabilidad different polymeric films (low density polyethylene and polyurethane) for laminated with polyethylene foam for automotive applications. The improvement in the adhesive properties has been studied through changes in the surface energy through the determination of contact angles for different exposure times and different liquids. In addition, samples were treated with plasma subjected to a process of aging to estimate the durability of treatment as many of the species generated show high volatility.

Author: PÉREZ ÁLVAREZ LEYRE.
Year: 2006.
University: PAÍS VASCO [www.ehu.es].
Place of defense: FACULTAD DE CIENCIA Y TECNOLOGÍA.
Place of preparation: CIENCIA Y TECNOLOGÍA.

Summary: The microgeles are macromolecules entrecruzadas with colloidal dimensions, which are very advantageous compared to the more conventional materials that have common properties with both solid particles such as polymers linear or macrogeles. They have a porous structure that gives swelling properties similar to those of their counterparts macrogeles. In recent times have been extensively studied the microgeles able to respond to external stimuli, especially compared with pH, because of their potential applications in the controlled release and the recovery of contaminants from wastewater. These microgeles pH-sensibles comprise polymeric colloidal with parent groups ionizables acid or base. This report was the synthesis and characterization of microgeles reagents which were eventually transformed into pH -sensibles by funcionalización of them through chemical modification postsintética. Moreover, we know that there is a tumor specificity between molecules and folic acid and folate conjugates to be internalized in the cancerous cells originate acid pH (). Based on these data in this report has designed a nanoingenio consisting of a mikcrogel base for the release of anticancer drugs in the new forms of anti-cancer therapy. It proceeded to the vectorization of microgeles reagents with folic acid and funcionalización the same with cationic functional groups capable of responding to the pH differences between tumor and healthy tissue.