As a promising material to replace corrosive steel reinforcements in concrete, glass fiber reinforced plastics (GFRP) have received enough interest as well as debates relating to their long term performance under moisture penetrating/alkali attack environment and their susceptibility to higher temperatures. The study presented in this thesis utilized vinyl ester/clay nanocomposites to alleviate the above concerns by combining unique barrier properties and thermostability of matrix nanocomposites with excellent mechanical performance of GFRPs. To verify the validity of hybridizing these two materials, GFRP composites with/without nanoclay in the matrix were fabricated and subjected to alkaline solutions for different exposure times of ageing. The effects of clay layered structure on the...[ Read more ]

As a promising material to replace corrosive steel reinforcements in concrete, glass fiber reinforced plastics (GFRP) have received enough interest as well as debates relating to their long term performance under moisture penetrating/alkali attack environment and their susceptibility to higher temperatures. The study presented in this thesis utilized vinyl ester/clay nanocomposites to alleviate the above concerns by combining unique barrier properties and thermostability of matrix nanocomposites with excellent mechanical performance of GFRPs. To verify the validity of hybridizing these two materials, GFRP composites with/without nanoclay in the matrix were fabricated and subjected to alkaline solutions for different exposure times of ageing. The effects of clay layered structure on the residual mechanical and thermomechanical properties and the barrier resistance to moisture and alkali ion were specifically studied. In addition to bundled GFRP composites, the residual strength and morphological change on the fiber surface was further investigated by ageing single glass fibers with neat polymer/nanocomposites coatings in an alkaline environment. Moreover, thermal decomposition and flame retardance of GFRP-clay nanocomposites was studied with the aid of thermogravimetric and cone calorimeter analysis. Results indicated significantly enhanced resistance to moisture/alkali after clay incorporation in the GFRP matrices. With MMT-vinylester nanocomposites as a coating, both improved residual properties and deflated eroding rate of single glass fiber were obtained. Regarding to thermal / flammable performance of the hybrid composites, although there’s no big change in the thermal decomposition behavior, flame retarding effects were remarkably observed after clay was introduced into the FRP matrix.

Key words: Glass fiber; FRP; Vinylester; Nanoclay; Nanocomposites; Alkaline environment; Residual properties; Thermal stability; Flame Retardance.