摘要
以超临界CO2 为发泡剂 ,用自行研制的电磁动态发泡模拟机 ,将机械振动力场引入到PS微孔塑料成型过程中 ,初步研究了稳态剪切力场和动态剪切力场对微孔塑料气泡成核的影响。实验发现 ,提高转速可以提高熔体的剪切应力 ,从而提高气泡成核率 ,但不如施加振动效果明显。施加振动后 ,泡孔直径随振幅和振频的增加而减小 ,泡孔密度随振幅和振频的增加而提高。在低温 (13 0℃ )、低压 (9MPa)下制备出泡孔直径约为 2 0 μm、泡孔密度约为6× 10 7个 /cm3 的微孔塑料。
The effects of steady and dynamic shear stress fiel d on bubble nucleation for microcellular plastics were analyzed during the molding process of microcellular PS using supercritical carbon dioxide as the foaming a gent. The results showed that the imposed vibration may increase effectively the bubble nucleation rate, which was better than that via increasing rotation spee d. With vibration imposed, cell diameter decreased and cell density increased wi th increasing amplitude and frequency. The microcellular plastics with cell diam eter about 20 μm, cell density about 6×107 cells/cm3 were prepared under a low temperature (130 ℃) and a low pressure (9 MPa).
出处
《中国塑料》
CAS
CSCD
北大核心
2004年第11期63-66,共4页
China Plastics
基金
教育部科学技术研究重点项目 (教技司 [0 1] 2 2 4号
0 113 8)
高等学校博士学科点专项科研基金 (2 0 0 2 0 5 610 0 2 )
EYTP
关键词
微孔塑料
超临界二氧化碳
振动
成核
microcellular plastics
supercritical carbon diox ide
vibration
nucleation