Patent ID: 8759474
Filing Date: 2014-06-24
Classification: C07C,C08G,C09K,Y10T

Abstract:
1. A method for producing a liquid crystal polyester, which comprises the following steps of: (1) polycondensing a mixture of 70.5 to 71.5 mol % of a compound represented by the formula (I) with 28.5 to 29.5 mol % of a compound represented by the formula (II) (the total of both compounds is 100 mol %) at 260 to 350° C. to form a prepolymer, wherein the prepolymer has a flow initiation temperature of 200° C. or higher, and the mixture is polycondensed until reaching the temperature which is at least 30° C. lower than the polycondensation temperature; (2) removing the prepolymer in a molten state, followed by solidification and further grinding to produce prepolymer particles having a particle size of 3 mm or less; and (3) subjecting the prepolymer particles to a heat treatment at 200 to 310° C. under circulation of an inert gas while remaining in a solid phase state; wherein R wherein R