| 摘要 |
<p>1534192 Oxidized pitch fibres UNION CARBIDE CORP 26 March 1976 [27 March 1975] 12261/76 Heading C1A An oxidized pitch fibre having a high degree of flexibility and handleability is made by spinning a pitch fibre from a non-thixotropic carbonaceous pitch having a mesophase content of 40-90% by weight which under quiescent conditions forms a homogeneous bulk mesophase having large coalesced domains; and heating the spun fibre in an oxygen-containing atmosphere at from 250-500‹ C. for a time sufficient to oxidize the fibre to an oxygen content of from 17-30% by weight to produce a fibre having a tensile strength of at least 30,000 p.s.i. and a strain-to-failure of at least 5%. The oxidized pitch fibre, which may be of 6 to 14 microns diameter, may be knitted or woven into cloth which may be carbonized by heating in an inert atmosphere at from 1000-2500‹ C., and further heated if desired in an inert atmosphere to from 2500-3300‹ C. Carbon fibre may be made by spinning a pitch fibre as above and heating the spun fibre in the oxygen-containing atmosphere at from 250-500‹ C. for a time sufficient to render it infusible and carbonizing the infusible fibre by heating in an inert atmosphere; the said spun fibre being oxidized to an oxygen content of 17-30% by weight to produce a fibre having a tensile strength of at least 30,000 p.s.i. and a strain-to-failure of at least 5%.</p> |
