𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Thickness–direction thermal-expansion measurements

✍ Scribed by Ravi F. Saraf; Ho-Ming Tong; Tze W. Poon; B. David Silverman; Paul S. Ho; Angelo R. Rossi

Publisher
John Wiley and Sons
Year
1992
Tongue
English
Weight
490 KB
Volume
46
Category
Article
ISSN
0021-8995

No coin nor oath required. For personal study only.

✦ Synopsis

Thermal expansivity in the thickness direction for three commercially synthesized and processed polyimide films, PMDA-ODA, BPDA-ODA, and BPDA-PDA, have been measured. The expansivity in the thickness direction is significantly higher than that in the in-plane direction. The observed anisotropy is explained by the orientation texture of the films. The differences in the expansivity is explained by the molecular conformation of the chain. The latter is calculated by energy minimization excluding the entropic effects. The conformation analysis reveals a helical-like conformation for ether-linkage-containing chains, which explains the higher expansivity in PMDA-ODA as opposed to BPDA-PDA. The possibility of helical conformation in PMDA-ODA and BPDA-ODA is novel.

📜 SIMILAR VOLUMES

Measurements of thermal expansion in YMn
Measurements of thermal expansion in YMn2H1
✍ H. Figiel; J. Żukrowski; E. Gratz; M. Rotter; A. Lindbaum; A.S. Markosyan 📂 Article 📅 1992 🏛 Elsevier Science 🌐 English ⚖ 154 KB
Interferometric measurement of thermal e
Interferometric measurement of thermal expansion
✍ V. Kurzmann; J. Stöhr; M. Tochtrop; R. Kassing 📂 Article 📅 1989 🏛 Elsevier Science 🌐 English ⚖ 282 KB

The temporal and spatial propagation of heat in a dielectric medium has been studied by observing the thermal expansion using a differential laser interferometer which was initially built for profilometry. It is demonstrated that topographical and thermal information can be obtained simultaneously.