| 摘要 |
PURPOSE:To obtain a flame-retarding polyester composition improved in flame retardancy, mechanical properties and residence stability during molding by mixing a melt-anisotropic polyester with a specified polybromostyrene and a filler. CONSTITUTION:A bromostyrene monomer comprising 60wt.% or above dibromostyrene and optionally monobromostyrene and tribromostyrene is polymerized to obtain a polybromostyrene (A) mainly consisting of structural units of the formula and having a number-average molecular weight of 1X10<3>-30X10<4>, a weight-average molecular weight of 2X10<3>-120X10<4>, an apparent density of 1.0g/cm<3> or above, a compression density of 1.1g/cm<3> or above, and an average pore diameter of 2.5mum or below. 100 pts.wt. melt-anisotropic polyester comprising units selected from among aromatic hydroxycarboxylate units, aromatic dioxy units, aromatic dicarbonyl units, ethylenedioxy units, etc., is mixed with 0.5-60 pts.wt. polymer A and 0-200 pts.wt. filler desirably glass fiber. |
