Repositori URV

Identificador: TDX:769

Handle: https://hdl.handle.net/20.500.11797/TDX769

Autors:
Espinosa Fernandez, Manuel Alejandro

Resum:
Natural and synthetic organic polymers are inherently combustible and in presence of heat and oxygen source burn easy and quickly. Although in the last years there has been an increment in the number of heteroatoms used in flame retardant compounds, the market is still dominated especially by compounds that contain halogens, like chlorine and bromine. These compounds are exceptionally troops but they have the shortcommings as the increase in the quantities of smoke and toxic gases and corrosive decomposition products that come off during the polymer combustion. As alternative to these a new class of thermostable resins chemically based in 3,4-dyhidro-2H-1,3-benzoxazines has arisen. Its synthesis is of great simplicity and it is carried out by formaldehyde condensation with phenols in presence of aromatic amines in a fixed molar relationship. At the same time another of the approaches used recently has been the use of organophosphorated compounds that have demonstrated good capacity like flame retardants for epoxy resins because they generate less toxic gases and smoke that the halogenated compounds. The general objective of this work has been the development of new fire retardant thermosettings systems, keeping the material properties and environmentally friendly. The goals is to improve the good properties of some standard materials, phenolic and epoxy resins, but introducing the non inflammability character by means of new ignifugation systems, based on phosphorous and nitrogen, alternative to the classic halogenated systems widely used at the present time. The synthesis and characterization of novolac resin systems modified in different proportions with benzoxazine rings, using a new synthetic method based on the use of 1,3,5-triphenilhexahydro-1,3,5-triazine has