Tesis doctoral de Erica María Vallejo Ortiz
The objective of this tesis is the set up of a chemical-physical test using the iodine sorption technique. The application of this technique on polyamide 6 fibers has detected differences of fine structure between the following substrates: fibers of the same type and different origin, substrates from different spinning speeds and with different stretch ratios and finally thermo sealing substrates to different temperatures. the interaction between iodine and the polyamide 6 fibers by means spectroscopy ftir were studied. finally the dyeing behavior of the substrates has studied to compare the differences of dye absorption with the differences of microstructure calculated by iodine sorption. the development of the iodine sorption for polyamide 6 fibers has detected differences of fine structure in substrates that differ in their process of manufacture or textile processing. the iodine sorption tests realized on continuous thread of the same characteristics coming from different producers indicated the existence of small differences among them. the iodine sorption realized in threads poy is slightly superior to the realized to threads fdy (totally stretched). The iodine sorption is superior for coming from poy that stops coming from loy. in the experimental conditions of this work, the variation of the stretch ratio in continuous threads does not modify the sorption iodine values, which suggests very similar global structures. The iodine sorption of staple fiber studied is very sensible to the variations of stretch ratios, being observed a good correlation of negative sign between this variable and the iodine sorption to the different temperatures. a thermal sealed treatment to 160ºc produces a diminution of the iodine sorption respect to the original weave, however increases in the thermal sealed temperature (170, 180 and 190ºc) do not produce appreciable changes. the dyeing tests realized on continuous threads of the same characteristics coming from different producers indicate the existence of small differences among them when they are dyed individually with an acid dye, with a combination of acid dyes or with a disperse dye. in a competitive dyeing with all the substrates, majors take place differences between threads of different producers. The substrate that absorbs more acid dye (a3) is one of those of smaller cristalinidad, also is one of those of smaller orientation and the one than has minor amount of amino-terminals groups. the dyeing behavior of a thread poy and two threads fdy (coming from a thread poy and of loy) with an acid dye only and with the combination of the acid dyes used in individual dyeing, gives differences of dye absorption very small. in competitive dyeing with the three together substrates, the thread poy is the one that it dyes more, agreeing that is the one of smaller cristalinidad and the one than more groups amino-terminals contains. in the experimental conditions of this work, the variation of the stretch ratio in continuous threads does not modify the values of dye absorption. It is valid in individual dyeing and competitive dyeing, whatever the type of dye. The same happens with the combination of the acids dyes. the stretch ratio of staple fiber studied has a great influence in the dyeing behavior, mainly in competitive dyeing with acids dyes. The dye absorption diminishes when increasing the stretch ratio. the thermal sealing substrates dye in separated dyeing present differences of absorption, that depend of the dyeing system applied. In the case of disperse dye the difference is only 0.7%, imperceptible for the human eye. the influence of the thermal sealed temperature is much greater in competitive dyes. Concretely the differences between the extreme values of the dye absorption oscillate between the 27 and 39%. the competitive dyeing of weaves thermo sealing to different temperatures with an acid dye indicates that the smaller dye absorption takes place in the weave thermo sealing to 160ºc. When it is dyed with a combination of acids dyes, the behavior is similar but the smaller dye absorption appears to 170ºc, which means the presence of a minimum of absorption. mainly in competitive dyeing, the evolution of the dye absorption according to the thermal sealed temperature depends of the dyeing system used. It is probable that is probable that in this aspect influences the molecular size of dyes used. a good linear relation between the iodine sorption and the dye absorption exists for the majority of the substrates and with all the applied dyeing systems.
Datos académicos de la tesis doctoral «La sorcion de yodo como metodo fisico-quimico de caracterizacion de la estructura fina de las fibras de poliamida 6.comparacion con las propiedades tintoreas«
- Título de la tesis: La sorcion de yodo como metodo fisico-quimico de caracterizacion de la estructura fina de las fibras de poliamida 6.comparacion con las propiedades tintoreas
- Autor: Erica María Vallejo Ortiz
- Universidad: Politécnica de catalunya
- Fecha de lectura de la tesis: 16/07/2008
Dirección y tribunal
- Director de la tesis
- Josefina Maillo Garrido
- Tribunal
- Presidente del tribunal: joaquín Gacén guillén
- pilar Erra serrabasa (vocal)
- albert Manich bou (vocal)
- milena Dimtchova tzvetkova (vocal)