| 摘要 |
(57) Sintered compacts made of aromatic polyesters, produced from diphenols such as 1,1-bis(4-hydroxyphenyl)-1-phenyle-thane or 9,9-bis(4-hydroxaphenyl)fluorene, as well as phthalic acid halides, have one or several glass transition temperatures between 220 and 400 .degree.C and a tensile strength above 40 N/mm2, preferably above 60 N/mm2. In order to produce the sintered compacts, the polyester powder is subjected to a pressure above 3000 N/cm2 in a closed mould. The mould is slowly heated, then maintained for a longer period above the glass temperature and slowly cooled down once again. While it cools, pressure can be reduced. Cross linking occurs in the polyester mass during sintering, increasing the fastness to solvents. These sintered compacts are generally useful as semi-finished products or preformed prefabricated elements, from which the desired articles can be produced by machining.
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