Effect of the aggressive environment on the damage of a glass polyester composite developed by hand layup process

This work treats the behavior of a glass fibre/unsaturated polyester (UP) composite with structural deffects subjected to the attack of two corrosive solutions: H2SO4 and NaOH. The gravimetric analysis, the uptake mass of the resin, and the interfaces in the composite are established according to the proportion of the matrix/composite. The obtained results showed that, in the acidic solution, the glass fibre and the fibre/matrix interface absorption share is more significant than the alkaline solution. While the Fourier transform infrared analysis (FT-IR) of the UP resin revealed the presence of chemical degradation phenomenon (hydrolysis), the fibre corrosion was characterized by the atomic absorption analysis (AAS). The fibres/matrix interfaces degradation was confrmed by microscopic observations (SEM). The difusion kinetics of the both acid and alkaline solutions and chemical and mechanical degradation are afected by the presence of the pores in elaborated materia

Procédé de fabrication de structure en composite verre/polyester

92 p. : ill. ; 30 cmCe travail consiste en une caractérisation analytique et expérimentale d’un matériau composite stratifié en verre/ polyester préparé par le procédé moulage au contact et utilisé dans la fabrication des bateaux (pèche et plaisance). Cette caractérisation a pris en compte l’influence de la séquence de stratification et du mode d’élaboration (taux de catalyseur et température d’élaboration). L’analyse spectrale FT-IR de la résine avant et après durcissement a confirmé que la réticulation s’est produite avec des conversions assez élevées. Les tests de réactivité ont montré que l’augmentation de la concentration en catalyseur et l’augmentation de la température augmentent la vitesse de la réaction et réduisent le temps de gélification et de maximum d’exothermie. Les propriétés mécaniques sont optimales pour les échantillons élaborés à 40°C avec 1% de catalyseur et pour ceux élaborés à 20°C avec 2% de catalyseur. L’emplacement du roving dans la séquence de stratification joue un rôle prépondérant dans le mode de comportement du stratifié surtout pour la sollicitation de flexio

Effect of temperature and initiator on glass fibre/unsaturated polyester composite : cross-linking, mechanical properties

The influence of temperature (20–60°C) and initiator ratio (1–3%) on the cross- linking and mechanical properties of the matrix resin and of gla ss fibre/unsaturated polyester composite; prepared by hand lay-up process and us ed in marine structures, is studied. Reactivity tests have shown that the effect of temperature in crease is similar to that of initiator ratio. They increase reaction rate and reduce the gelation tim e and exothermic peak. Conversely, the Fourier transform infrared spectroscopy analyses have sh own that the final conversions of styrene and polyester vinyl groups are almost co mplete, and that whatever the chosen operating conditions. Tensile and bending tests have shown that the m echanical properties (Elastic modulus, tensile strength...) are optimal for the samples operated at 40°C with 1% of initiator and those operated at 20°C with 2% of initiato

Effect of the Aggressive Environment on the Damage of a Glass Polyester Composite Developed by Hand Layup Process

This work treats the behavior of a glass fibre/unsaturated polyester (UP) composite with structural defects subjected to the attack of two corrosive solutions: H2SO4 and NaOH. The gravimetric analysis, the uptake mass of the resin, and the interfaces in the composite are established according to the proportion of the matrix/composite. The obtained results showed that, in the acidic solution, the glass fibre and the fibre/matrix interface absorption share is more significant than the alkaline solution. While the Fourier transform infrared analysis (FT-IR) of the UP resin revealed the presence of chemical degradation phenomenon (hydrolysis), the fibre corrosion was characterized by the atomic absorption analysis (AAS). The fibres/matrix interfaces degradation was confirmed by microscopic observations (SEM). The diffusion kinetics of the both acid and alkaline solutions and chemical and mechanical degradation are affected by the presence of the pores in elaborated material