2005 Fiscal Year Final Research Report Summary
Time and Temperature Dependence of Cell Number and Cell Size of Foamed Plastics
| Project/Area Number |
16560082
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Materials/Mechanics of materials
|
|---|
| Research Institution | KANAZAWA INSTITUTE OF TECHNOLOGY |
|---|
Principal Investigator |
SHIMBO Minoru Kanazawa Institute of Technology, Faculty of Engineering, Professor, 工学部, 教授 (70142552)
|
|---|
| Project Period (FY) |
2004 – 2005
|
| Keywords | Foamed plastics / Cell number / Cell size / Foaming time / Decompression time / Foaming temperature / Viscoelastic behavior / Time-temperature eauivalency |
|---|
| Research Abstract |
The equivalency between the foaming temperature and the decompression rate (decompression time) of the cell number in foamed plastics will be discussed. The blowing agent was soaked into the resin as a solid state at high pressure under temperatures higher than the glass transition temperature of the resin. After foaming agent reached its saturation state, cell nucleation and cell growth were accelerated by decompression. Finally, cell growth was halted by cooling. The following results were obtained. (1)The cell density increases when the decompression rate is quick, i.e. the decompression time is shortened under the condition of low foaming temperature, and cell density decreases when the decompression rate is slow, i.e. decompression time is lengthened under the condition of high foaming temperature. (2)Equivalency is maintained between the temperature dependence and time dependence of the cell density of foamed PS, and it can express with one master curve.
Next, the equivalency betw
… More
een the foaming time and foaming temperature of the cell number in foamed plastics will be discussed. The blowing agent was soaked into the solid resin at high pressure under temperature lower than the glass transition temperature of the resin. After the blowing agent reached its saturation state, cell nucleation and cell growth were induced by heating various foaming temperatures higher than glass transition temperature and various foaming times after decompression. Finally, cell growth was halted by cooling. The following results were obtained. (1)Cell density of foamed PS and PC plastics shows time and temperature dependence as the cell density becomes large when foaming temperature is low and foaming time is short. (2)Equivalency is maintained between the foaming time and foaming temperature dependence of the cell density of PS and PC foamed plastics, and they can be expressed with one master curve respectively. These results seem to become one technique to select the foaming condition of foamed plastics having required cell densities. Less
|
