INVESTIGATION OF THE WATER ABSORPTION PROPERTIES OF PULTRUDED HYBRID COMPOSITE PROFILES

Pultrusion is a continuous process for the manufacture of fiber reinforced polymer matrix composite products having a constant cross section, such as rod stock, structural shapes, beams, channels, pipe and tube. Pultruded profile products have high structural integrity and mechanical properties. The water absorption characteristics of composite materials give serious concern, especially for their potential outdoor applications. It is also known that having a high water absorption tendency has negative effects on the mechanical, physical, chemical and optical properties of composite materials. This is why; it is undesirable that the polymer matrix, which is used in the production of the composite profiles by the pultrusion method, has high water absorption values. Fiber content is also a leading parameter and has a significant influence on the mechanical properties of composite materials. In this study; the water absorption characteristics and fiber contents of pultruded glass-carbon fiber reinforced polyester and vinylester hybrid composite profiles were experimentally investigated. Water absorption tests were performed by immersing composite specimens into water conditions according to ASTM D 570 standard. The fiber contents of composite specimens were determined by calcination method according to TS 1177 EN ISO 1172 standard. The results obtained from the experiments were analyzed and explained with necessary comments.