| Summary: | 碩士 === 國立中正大學 === 光機電整合工程所 === 95 === In this thesis, we studied glass transition temperature of polymer film by coarse-grained molecular dynamic simulation.
We divided simulation into two parts. The first part was no-wall simulation and used the calculated mean-square displacement to decide glass transition temperature. This result was compared with existing literature. The second part was single-wall simulation. We observed the effect of wall potential function and tried to use this result to explan the experimental phenomenon.
According to the no-wall simulation result, we found that when using staggered reflective boundary condition, we can get the glass transition temperature of polymer bulk even if the thickness below 10 s. ( The mean square of the radius of gyration about 4~5 s.) As the thickness change, the glass transition temperature in surface region also change.
At single-wall simulation, we created a wall has high value of interfacial energy. According to the single-wall simulated result, we found that the glass transition temperature of polymer film is higher than that of the bulk polymer.
|
|---|
