申请人:Sumitomo Chemical Company, Limited
公开号:EP1081173A2
公开(公告)日:2001-03-07
Provided is a process for producing an aromatic liquid crystalline polyester comprising the steps of:
charging into a reaction vessel 80 to 20 mol% of a compound of formula (I) and 20 to 80 mol% of a compound of formula (II):
wherein R1 represents a hydrogen atom, formyl group, acetyl group, propionyl group or benzoyl group, R2 represents a hydrogen atom, methyl group, ethyl group, propyl group, benzyl group or phenyl group, the R1 groups in formulae (I) and (II) may be the same as or different from each other, and the R2 groups in formulae (I) and (II) may be the same as or different from each other;
conducting a polycondensation reaction of the charged mixture at a temperature from 270 to 350°C to produce an aromatic liquid crystalline polyester having a flow temperature of 210°C or more and lower than the polycondensation reaction temperature by 30°C or more;
discharging the aromatic liquid crystalline polyester in a molten state from the reaction vessel and solidifying;
then, pulverizing the solidified polyester into particles having a particle size of 3 mm or less; and
heat-treating at a temperature from 200 to 310°C still in the solid state under an inert gas atmosphere;
wherein the flow temperature means the temperature (°C) at which the melt viscosity measured by a capillary type rheometer is 48,000 poise when a resin which has been melted by heating at a temperature raising rate of 4°C/min is extruded through a nozzle having an internal diameter of 1 mm and a length of 10 mm under a load of 100 kgf/cm2.
The aromatic liquid crystalline polyester has improved low temperature molding processability, and the film thereof has sufficient heat-resistance and excellent gas barrier properties.
本发明提供了一种生产芳香族液晶聚酯的工艺,包括以下步骤
在反应容器中加入 80 至 20 摩尔%的式 (I) 化合物和 20 至 80 摩尔%的式 (II) 化合物:
其中 R1 代表氢原子、甲酰基、乙酰基、丙酰基或苯甲酰基,R2 代表氢原子、甲基、乙基、丙基、苄基或苯基,式 (I) 和 (II) 中的 R1 基团可以相同或不同,式 (I) 和 (II) 中的 R2 基团可以相同或不同;
在 270 至 350°C 的温度下对加料混合物进行缩聚反应,生成芳香族液态结晶聚酯,其流动温度为 210°C 或以上,并比缩聚反应温度低 30°C 或以上;
将熔融状态的芳香族液态结晶聚酯从反应容器中排出并凝固;
然后,将凝固的聚酯粉碎成粒径为 3 毫米或以下的颗粒;以及
在惰性气体环境下,以 200 至 310°C 的温度对仍处于固态的聚酯进行热处理;
其中,流动温度是指在 100 kgf/cm2 的载荷下,以 4°C/min 升温速率加热熔化的树脂,通过内径为 1 毫米、长度为 10 毫米的喷嘴挤出时,用毛细管流变仪测得的熔体粘度为 48,000 poise 的温度(°C)。
这种芳香族液晶聚酯改善了低温成型加工性,其薄膜具有足够的耐热性和优异的气体阻隔性。