Coupling agent for reinforced polyolefines

Abstract

Ac electrical conductivity, DSC calorimetry and density measurements have been done on glass and crystalline phases for different compositions of the binary Na2MoO4−UO2SO4 system. The conductivity data show a positive dependence on Na2MoO 4 reaching a maximum at ca. 3:2 mole ratio Na2MoO4:UO2SO4. In contrast with the Na2SO4:UO2SO4 binary system where σglass>σcrystal for the 2:1 mole ratio, the Na2MoO4−UO2SO4 composition exhibits a higher σ for the crysta lline phase. The higher σcrystal versus σglass correlates with the increase in “free volume” for the crystal. The σ-T behavior for the glass of composit ion 0.63Na2MoO4:0.37UO2SO4 shows three distinct conductivity regimes or discontinuities prior to complete devitrification. The onset temperatures of these regimes correlate with the observed DSC thermal effects. These regimes and thermal effects prior to complete devitrification suggest the existence of stable higher energy intermediate, mixed crystal-glass, structural states in the glass phase. These results are discussed relative to results of parallel studies on Na4UO2(SO4)3, Na2O·2CaO·3SiO2, LiTi2(PO4)3 and Li2O·BaO·Nb2O5 systems already reported in the literature.