Abstract: A thermal insulation and fire protection felt product is provided. The felt product includes a first layer including a first plurality of nonwoven mechanically entangled oxidized polyacrylonitrile (PAN) precursor fibers bonded together by a first plurality of melted thermoplastic polyphenylene sulfide (PPS) fibers homogeneously mixed with the first plurality of mechanically entangled PAN precursor fibers. The first plurality of melted thermoplastic PPS fibers form a matrix of bond points between individual fibers of the first plurality of mechanically entangled PAN fibers. A second layer includes a second plurality of nonwoven mechanically entangled oxidized PAN precursor fibers bonded together by a second plurality of melted thermoplastic PPS fibers homogeneously mixed with the second plurality of mechanically entangled PAN precursor fibers.