A spinning method based on radiation-induced UV-curing reduces the technical requirements to a minimum. The spinning mass is applied in the form of UV-curable solvent-free resins.

Nanoporous SiO₂ hollow fibers derived from ORMOCER^® (hollow) fibers

The ORMOCER^® hollow fiber is an ideal initial point for purely inorganic silicate hollow fibers. The three-dimensional inorganic Si-O-Si network created within the fiber forms the backbone for the SiO₂ hollow fiber.

Pyrolysis causes a tightly constrained distribution of the pore radii in the nm range (0.7 to 3 nm). Apart from a high specific BET surface of up to 700 m2/g and a porosity of up to 60 percent by volume, these fibers also feature good resistance up to 100 MPa and relatively good flexibility.

Application

Possible applications of the new ORMOCER^® hollow fibers range from semipermeable membranes for the separation of substances to microcapillaries or tubes with variable mechanical properties that are used solely for transport purposes. One of the most likely applications for nanoporous hollow fibers is in the field of gas separation at elevated temperatures (up to 400°C).