알칼리 환경에 대한 GFRP 복합재료의 내구성 향상에 관한 연구(1)

Study on the durability improvement of GFRP composites in alkaline environment (1)

The effect of alkaline environmental condition on durability of GFRP composites according to additives has been investigated. Additives used were polyvinyl alcohol (PVA), kaolin and alumina powder. Weight gains increased with immersion time in all GFRP composites at $80^{\circ}C$. But weight gain of specimen added PVA did not differ through the whole immersion time in both tap water and alkaline solution at 20 and $80^{\circ}C$. Tensile strength decreased with immersion time in all environment conditions. Tensile strength of GFRP composites regardless of additives decreased rapidly up to 5 days of immersion and then decreased slowly up to 30 days in alkaline solution environment at $80^{\circ}C$. The weight gains were not much difference in both tap water and alkaline solution at $20^{\circ}C$. But the ones of GFRP composites added PVA was smaller than the composites without additive in all aqueous at $20^{\circ}C$. Test strength of GFRP composites added polyvinyl alcohol has improved through the whole immersion time in both tap water and alkaline solution environment at $20^{\circ}C$.