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Abstract
Polyhydroxynaphthalene (PHN) and polyresorcinol (PRS) are polymerized using the method developed by EI-Garf et. al. It is shown that the optimum conditions for polymerization are at a polymerization temperature of 150°C. Polymerization time of 4 hours and molar ratio of (polymer: AICh: FeCh) is (1: 1 :2).
DrA of po lyres orcinol shows an exothermic peak which begins at 407.7 °C and end at 432°C with average peak at 420.7°C which is due to decomposition which mean that drastic decomposition begins at this temperature. The heat evolved is 5910.925 J.lV/mg. Before this temperature there is an endothermic beak begin at 32.1 °C and end at 121.5 °C with average peak at 84.8 °C and heat absorbed is 338.683J.lV/mg.
The exothermic peak doesn’t show any crystallization because of there is no phase transition.
The dielectric constant is 48.275 for PHN and is 35.96 for PRS. Pure PHN and PRS have the highest dielectric constant when compared with those of well known dielectrics used in industry. Coating the PHN with polystyrene decreases the dielectric constant from 48.275 to 40.5. Further increase of percentage polystyrene coating to 2% decreases the dielectric constant to 20 Coating the PRS with polystyrene decrease the dielectric constant from 35.96 to 28.37. Further increase of percentage polystyrene to 3% decreases the dielectric constant to 12.38.PHN has a dielectric constant 19.3 times. 20.9 times, 14.6 times, 12 times, 12.1 times, 6 times, 22.9 times, 8.7 times, 3times and 8.7 times higher than that of polystyrene, polyethylene, PVC, nylon, rubber, phenolics, Teflon, porcelain, germanium and diamond, respectively But less than polypyrogallol by 0.83 times.
The pure PHN has an A.C and D.C electric strengths of 600 and 1000 V/mm respectively. And the pure PRS has an A.C and D.C electric strengths of 1100 and 500 V/mm respectively. Increasing the percentage coating of polystyrene increases both values for PHN and PRS to a maximum of 1000 V/mm for A.C electric strength and 1460 V/mm for D.C electric strength for PHN and to a maximum of 1500 V/mm for A.C for PRS. Increasing percentage coating with polystyrene will increase electric strength.
PHN has a large capacity to store a charge. The dissipation factor decreases with increasing percentage coating with polystyrene.
PRS has a dielectric constant 14.3 times. 15.6 times, 10.9 times, 8.9 times, 9 times, 5 times, 17.1 times, 6.5 times, 2.2times and 6.5 times higher than that of polystyrene, polyethylene, PVC, nylon, rubber, phenolics, Teflon, porcelain, germanium and diamond, respectively But less than polypyrogallol by 0.62 times.
PHN has a large capacity to store a charge of 60.4 PF which higher than PRS.l.34 time. The capacitance ofPHN and PRS are lower than that of PPG by 0.83 and 0.63 times Respectively.