Effect of Ca3(PO4)2 doped to basalt on the structure, electrical characteristics and spinnability

Ca3(PO4)2 is selected to be added to the basalt to simulate basalt mixed sludge in order to produce glass and continuous fiber. XRD and Raman are used to analyze basalt glass with varied Ca3(PO4)2 additions. Basalt glass is amorphous, according to XRD measurements. However, Ca3(PO4)2 alters the Raman spectra of basalt glass noticeably. Raman results show Ca3(PO4)2 increases the degree of polymerization of the glass, but the degree of polymerization decreases with the further increase of Ca3(PO4)2 content. The dielectric characteristics are tested at a frequency of 1 MHz. When the addition amount of Ca3(PO4)2 is 1 g, it has the lowest dielectric constant of 6.567. When the addition amount is 2 g, it has the lowest dielectric loss of 0.0026. The volume resistivity of the sample without Ca3(PO4)2 is 4.227 × 1013 Ω· cm (25 °C). With the increase of Ca3(PO4)2 content, the volume resistivity decreases, reaching the lowest 1.78 × 1013 Ω·cm when the addition amount is 2 g (25 °C). With the increase of Ca3(PO4)2 content, the fiber diameter becomes larger, the crack decreases and the fracture frequency decrease. So the sludge can be considered as an addition in the continuous fiber production.