Thesis (M.Eng)--Chulalongkorn University, 2009

In this study, the influences of gasohol on physical and mechanical properties of glass fiber reinforced polyamide 6 (PA6) composites were investigated. The pellets of neat PA6 and PA6 compound with 15 wt% and 30 wt% glass fiber were used. Test specimens were prepared by compression and injection molding machines.These specimens were immersed in 4 different test fuels, namely, C(E0)A, C(E20)A, C(E85)A, and C(E100)A at room temperature for 16 weeks. The test fuels were changed every 3 weeks. Morphology, water absorption, mass and dimension change, tensile, flexural, compressive and impact properties were examined by scanning electron microscope (SEM), balance, universal testing machine (INSTRON) and impact tester, respectively. The experimental results showed that the PA6 matrix had an excellent adhesion to glass fiber reinforcement. The glass fiber could improve the mechanical properties of the composites and mass and dimensional stability of specimens by reducing amorphous region while increasing crystalline region. Test fuels containing alcohol, i.e. C(E20)A, CE(85)A and C(E100)A affected the tensile strength, flexural strength and Young’s modulus of both unreinforced and reinforced PA6 composites more than C(E0)A due to adsorption of water and alcohols from C(E20)A, CE(85)A and C(E100)A by both unreinforced and reinforced PA6 composites.