Investigating the influence of free volume and temperature on time-temperature superposition principle by MD simulation
Polymers and their composites are extensively utilized in the aerospace, energy, and automotive industries due to their lightweight properties, ease of manufacturing, high impact resistance, and other advantages. These materials are crucial for applications where performance and durability under var...
Saved in:
| Main Authors: | , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
The Japan Society of Mechanical Engineers
2024-09-01
|
| Series: | Mechanical Engineering Journal |
| Subjects: | |
| Online Access: | https://www.jstage.jst.go.jp/article/mej/11/6/11_24-00242/_pdf/-char/en |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850251277403947008 |
|---|---|
| author | Shihong YUAN Takenobu SAKAI |
| author_facet | Shihong YUAN Takenobu SAKAI |
| author_sort | Shihong YUAN |
| collection | DOAJ |
| description | Polymers and their composites are extensively utilized in the aerospace, energy, and automotive industries due to their lightweight properties, ease of manufacturing, high impact resistance, and other advantages. These materials are crucial for applications where performance and durability under varying environmental conditions are critical. Accurately predicting the viscoelastic behavior of polymers is essential for ensuring their reliability and durability. The time-temperature superposition principle (TTSP) is widely used to predict long-term viscoelastic properties, such as creep and stress relaxation, by making a master curve from short-term experimental data at various temperatures. Despite its widespread application, the molecular mechanisms of TTSP are not fully understood. To approach this issue, molecular dynamics (MD) simulations were employed to investigate TTSP mechanisms at the molecular level. Creep analyses were conducted at various temperatures with both with constant density and pressure using polypropylene as the model polymer to examine the effect of density on TTSP. The purpose of the simulations is to explain the basic mechanisms causing viscoelastic behavior, including the effect of chain interactions, potential energy changes, and free volume changes. The results indicate that the change of free volume has an important role in the formation of the TTSP master curve. Additionally, torsional potential energy is highly responsive to temperature changes, whereas non-bonding potential energy is more influenced by density changes. Furthermore, a linear relationship was found between changes in internal molecular angles (bond angle and torsion angle) and molecular chain structures (kinks and entanglements) with shear creep compliance. |
| format | Article |
| id | doaj-art-ba00b5c9987c44caa07952f83daef119 |
| institution | OA Journals |
| issn | 2187-9745 |
| language | English |
| publishDate | 2024-09-01 |
| publisher | The Japan Society of Mechanical Engineers |
| record_format | Article |
| series | Mechanical Engineering Journal |
| spelling | doaj-art-ba00b5c9987c44caa07952f83daef1192025-08-20T01:57:55ZengThe Japan Society of Mechanical EngineersMechanical Engineering Journal2187-97452024-09-0111624-0024224-0024210.1299/mej.24-00242mejInvestigating the influence of free volume and temperature on time-temperature superposition principle by MD simulationShihong YUAN0Takenobu SAKAI1Graduate School of Science and Engineering, Saitama UniversityGraduate School of Science and Engineering, Saitama UniversityPolymers and their composites are extensively utilized in the aerospace, energy, and automotive industries due to their lightweight properties, ease of manufacturing, high impact resistance, and other advantages. These materials are crucial for applications where performance and durability under varying environmental conditions are critical. Accurately predicting the viscoelastic behavior of polymers is essential for ensuring their reliability and durability. The time-temperature superposition principle (TTSP) is widely used to predict long-term viscoelastic properties, such as creep and stress relaxation, by making a master curve from short-term experimental data at various temperatures. Despite its widespread application, the molecular mechanisms of TTSP are not fully understood. To approach this issue, molecular dynamics (MD) simulations were employed to investigate TTSP mechanisms at the molecular level. Creep analyses were conducted at various temperatures with both with constant density and pressure using polypropylene as the model polymer to examine the effect of density on TTSP. The purpose of the simulations is to explain the basic mechanisms causing viscoelastic behavior, including the effect of chain interactions, potential energy changes, and free volume changes. The results indicate that the change of free volume has an important role in the formation of the TTSP master curve. Additionally, torsional potential energy is highly responsive to temperature changes, whereas non-bonding potential energy is more influenced by density changes. Furthermore, a linear relationship was found between changes in internal molecular angles (bond angle and torsion angle) and molecular chain structures (kinks and entanglements) with shear creep compliance.https://www.jstage.jst.go.jp/article/mej/11/6/11_24-00242/_pdf/-char/entime-temperature superposition principlecreepfree volumepolypropylenemolecular dynamics simulation |
| spellingShingle | Shihong YUAN Takenobu SAKAI Investigating the influence of free volume and temperature on time-temperature superposition principle by MD simulation Mechanical Engineering Journal time-temperature superposition principle creep free volume polypropylene molecular dynamics simulation |
| title | Investigating the influence of free volume and temperature on time-temperature superposition principle by MD simulation |
| title_full | Investigating the influence of free volume and temperature on time-temperature superposition principle by MD simulation |
| title_fullStr | Investigating the influence of free volume and temperature on time-temperature superposition principle by MD simulation |
| title_full_unstemmed | Investigating the influence of free volume and temperature on time-temperature superposition principle by MD simulation |
| title_short | Investigating the influence of free volume and temperature on time-temperature superposition principle by MD simulation |
| title_sort | investigating the influence of free volume and temperature on time temperature superposition principle by md simulation |
| topic | time-temperature superposition principle creep free volume polypropylene molecular dynamics simulation |
| url | https://www.jstage.jst.go.jp/article/mej/11/6/11_24-00242/_pdf/-char/en |
| work_keys_str_mv | AT shihongyuan investigatingtheinfluenceoffreevolumeandtemperatureontimetemperaturesuperpositionprinciplebymdsimulation AT takenobusakai investigatingtheinfluenceoffreevolumeandtemperatureontimetemperaturesuperpositionprinciplebymdsimulation |