CS198595B1 - Method of preparing heatproof fibres - Google Patents

Description

The invention relates to a process for preparing refractory carbonation fibers.

Specially treated fibers represent one of the modem technical materials, and the attention of the technology is still focused on the addition of high modulus fibers for stiffening. For its preparation, a number of carbonization processes are known which, in addition to the required high parameters, are carried out in complex high-temperature apparatuses and at the same time dispose of the carburizing products. Recently, refractory fibers have become of interest. production by known processes in complex high temperature, apparatus disadvantage economically.

Therefore, it has been found expedient to find a method for producing these refractory fibers using considerably simpler devices and thus more economically advantageous processes.

This object has been achieved by a process for preparing refractory fibers according to the present invention, which consists in that the carbonization is carried out by passing the burner flame at a fiber temperature of 1100 to 1500 ° C at a passage rate corresponding to a fiber inlet temperature of 500,000 to 3,000,000 Whereby the fiber is optionally blown with an inert gas such as nitrogen or argon or wetted with a non-flammable liquid such as chloroform prior to entering the flame.

By the process according to the invention, a fiber can be prepared both endless and finite using all types of carbizable fibers in the texmostabill state and the advantage of the method is

198 595 not only considerably inexpensive regulations and 1 operation, but 1 direct combustion of carbonization products, so there is no need for equipment for its likvidaoi.

Example 1

A refractory fiber according to the invention was produced with a polyacrylonitrile fiber stabilized at 300 ° C for air for 2 hours by passing it through a flamed Keeker burner at a fiber filament xy speed such that it corresponded to an increase in fiber temperature at 2,500,000 ° C / hour, was 1130 ° 0. The fiber was refractory and showed a tensile strength of 0.5 QPa and an elastic nodule of 65 ore

Example 2

A refractory fiber according to the invention was produced from a polyacrylonitrile fiber stabilized at air at 300 ° C for 2 hours by passing through a planenen Keoker burner, e.g. The rate of passage of the filament was such that it corresponded to an increase in the temperature of the filament at a rate of 1,800,000 / hour, while the filament was tolerated by chloroform before being introduced into the flame. The brewing temperature was 1100 ° 0. the fiber produced was refractory and exhibited a tensile strength of 0.5 OPa and an elastic nodule of 89 GPa

Example 3

Pyle made a refractory fiber according to the invention of a polyaczylonitsil fiber stabilized at air at 300 ° C for 2 hours by passing it through a planenen burner, while the rate of passage of the planenen was such that it corresponded to a rate of temperature increase of 835,000 ® / hr. argon flow at a flow rate of 0.01 l / nin was achieved and the process temperature was 1130 ®. The fiber produced was refractory and exhibited a tensile strength of 1 GPa and an elasticity of 104 GPa.

Example 4

The refractory fiber produced according to the invention was made from an oelulosic fiber of ternoetabilised weight from a catalytic lance of a crosslinking agent and its burner travel was such that it corresponded to the temperature increase at the fiber temperature of 1 800 000 ° C. The produced fiber was refractory and showed a tensile strength of 470 KPa

Example 5

The refractory fiber produced according to the invention was produced from the fiber obtained from the tar pulp fiber, temporarily stabilized by the expansion of the furnace, its throughput of the burner, the rate of increase in temperature of the fiber was 1,000,000 ° C / hour and the frying temperature was 1300 °. The produced fiber was refractory and showed a tensile strength of 500 KPa.

Claims (3)

CLAIMS 1. A method for preparing refractory fibers by carbonizing a stabilized carbonizable fiber, said fiber being passed through a burner flame at a fiber temperature of 1100 ° C to 1500 ° C at a flame passage rate which corresponds to a fiber temperature rise of 500,000 ° C to 3,000 000 ° C / co. 2. A method according to claim 1, characterized in that the fiber is blown with an inert gas such as argon or nitrogen before the flame enters. Method according to claim 1, characterized in that the fiber is wetted with a non-flammable liquid, such as chloroform, before entering the flame.