摘要
聚酰亚胺具有许多优异的性能,因此在工业中得到了广泛应用。目前对聚酰亚胺玻璃化转变的研究都局限于实验法,但由于实验条件的限制如高温、高压等,通过实验方法难以得到实验数据,影响人们对聚酰亚胺玻璃化转变的认识。利用Materials Studio v7.0对聚酰亚胺玻璃化转变进行模拟,计算出4种不同聚酰亚胺在不同温度下的密度,从而得到比体积与温度关系图,再根据Fox和Flory提出的自由体积理论得到聚酰亚胺的玻璃化转变温度。模拟计算出的玻璃化转变温度与实验值基本一致,表明可以通过动力学模拟研究聚酰亚胺玻璃化转变。
Due to their excellent properties such as excellent thermal stability, environmental resistance, good mechanical strength and so forth, polyimides are used in a wide range of field. Polyimides have attracted much attention for the past few years. Glass transition temperature （Tg） directly influence the usage temperature of polyimidesl Therefore the study of Tg is significant for production and utilization of polyimides. So far, experimental study is the most common method to measure the Tg of polyimide. However, there are many shortcomings including operation error and instrument error. In this work, the molecular dynamics simula- tion was employed to predict T, for polyimides with different structure. At first, the amorphous cell model of polyimide was built up with AC module in Materials Studio, and then the simulation was performed in NPT ensemble at 425--650 K. Finally, the specific volume was sketched out as function of temperature, and the least-square method was used to obtain the Tg.
出处
《材料导报》
EI
CAS
CSCD
北大核心
2017年第12期136-139,144,共5页
Materials Reports
基金
西南石油大学引进人才项目(201331010015)
关键词
聚酰亚胺
玻璃化转变温度
分子动力学模拟
polyimide, glass transition temperature, molecular dynamics simulation
