A Study Into Some Thermal Properties of Novolak and its Composites


The research involves using phenol-formaldehyde (novolak) resin as amatrix for making composite material, while glass fiber type (E) and asbestos fibertype chrysolite were used as reinforcing materials. The specimens of compositematerials were prepared from each type of all the fibers mentioned above withweight fraction of (60%) of their weight. After that the hybrid composite materialwas made by the addition of different types of these fibers in the same weightfraction, these specimens were made in different ratios of hexamethylenetetraminecontent including (10%) and (14%). Then the study on some thermal propertieswas carried out on all composites which were prepared and the results werecompared with those of novolak resin alone. The effect of reinforcement withfibers on the properties of resin was studied, too. Thermal properties were studiedincluding heat distortion temperature (HDT), thermal gravimetric analysis (TGA),erosion resistance by use of oxyacetylene burner and thermal conductivity. Ingeneral, the results have shown that after the reinforcement with differentfibers and types of improvement factors improve the thermal properties. Thepositive effect of increasing the hexamethylenetetramine is to increase mostproperties of resin and its composites have shown a new case, which combinesbetween the other reinforcement cases i.e. the possibility of combining propertiesin one material in a balanced form.