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In this study, high density polyethylene (PE) has been reinforced with a side chain LCP by graft copolymerization of p-benzophenoneoxycarbonylphenyl acrylate (BPOCPA). The mechanical and thermal behavior of the graft coproducts were investigated in relation to the structural changes (in unit cell parameters) of PE matrix. The crystalline melting temperature of PE, varying consistently with the poly(BPOCPA) content in the coproducts, significantly increased (from 131°C to 132-138°C). The unit cell dimensions, a and b, of the orthorhombic structure, the ab basal area and particle size of PE crystals initially expanded, and then consistently contracted with the graft content. The c parameter, however, remained relatively unchanged. Remarkable improvements were achieved in the tensile properties of the material; with the maxima of 38 % increase in tensile strength and 67 % increase in Young's modulus with the coproduct comprising 9.3 % poly(BPOCPA). These developments were found to be explained by the advances in the orientation and alignment of PE chains, conduced by greater chain mobility in the larger ab basal area and intensifying cohesive forces arising from the glassy nematic structured graft units.

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Aggregates are one of the most important raw materials used in the construction industry. It is almost impossible to create a structure without using aggregates. The worldwide mining industry generates 16·5 billion tons of aggregates annually. An increase in domestic and industrial areas limits the regional aggregate resources, and highlights the need to find new sources of aggregate. Difficulties in using regional resources force aggregate suppliers to transport aggregate over long distances, resulting in additional time and expense, as well as rapid deterioration of highway infrastructures. Thus, it is vitally important to use available aggregate resources effectively and to find new environmentally friendly potential aggregate resources to meet the increasing demand. Therefore, aggregate samples taken from two different aggregate resources in the Afyonkarahisar–Seydiler region of Turkey were examined. In order to determine the physical properties of crushed aggregate samples, standard tests were carried out to evaluate whether the volcanic aggregate samples were suitable to use in bituminous pavement layers. In the present study, four different aggregate samples were used: volcanic aggregate 1 (V1), volcanic aggregate 2 (V2), limestone 1 (L1) and limestone 2 (L2). The V1 and V2 samples were volcanic rocks taken from the Tekerek and Kepez areas, respectively. These samples had trachy-andesite composition based on their geochemical and petrographical observations. The L1 and L2 samples were provided from quarries in the Karacaoglan and Cobanlar areas, respectively. Both L1 and L2 samples have been currently used in hot-mix asphalt pavements. The test results indicate that the sample V1 made of volcanic aggregates displayed adequate performance on a wearing course with heavy traffic. Sample V2 did not display enough deformation resistance as a bituminous mix; however, it could be used for surface courses because of its good friction properties.