Preparation, thermal stability and mechanical properties of inorganic continuous fibers produced from fly ash and magnesium slag.

A large number of industrial solid waste resources urgently need to be recycled, so, fast-expanding the utilization area of these waste resources is a pressing task in today's China. The production of various slag wool fibers is an effective way due to the huge demand of thermal insulation materials. Besides, the preparation of slag continuous fibers is also a good choice because of its wide application fields. Two fly ash-based continuous fibers were successfully prepared by fly ash and magnesium slag, or add less feldspar, through melting at high temperature, following spinning into continuous fibers. Their samples were treated at different temperatures from 100 to 700 °C, and then investigate tensile strength and thermal resistance. As the same fly ash-based fibers, the tensile strength of two fibers in this study increase 115% and 28.3% than the fibers previously reported. Their utilization rates of solid waste resources are up to 100% and 80%, and far higher than 45% of the same fiber reported. FT-IR, SEM, Solid-state NMR analysis indicates that thermal action makes the Si structure without Al(Q,Q, and Q) transfer to Si structure containing Al(Q(3Al),Q(2Al), Q(1Al)), meanwhile, Al (AlO octahedron) was destroyed completely and converted into Al (AlO) and Al (Al[SiO]). Only some Al atoms participated in the formation of network structure in fiber, they contributed to the strength of fibers.