Impact of Nanoscale Confinement on Crystal Orientation of Poly(ethylene oxide)

✍ Scribed by Haopeng Wang; Jong K. Keum; Anne Hiltner; Eric Baer

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 514 KB
• Volume: 31
• Category: Article
• ISSN: 1022-1336
• DOI: 10.1002/marc.200900653

✦ Synopsis

Abstract

Using a layer‐multiplying coextrusion process to fabricate films with thousands of alternating polymer nanolayers, we report here a new crystalline morphology in confined polymer nanolayers and an abrupt transition in the crystallization habit. At higher temperatures, poly(ethylene oxide) crystallizes as large, in‐plane lamellae. A 5 °C change in the crystallization temperature produces an on‐edge lamellar orientation. The results point to a transition from heterogeneous nucleation to substrate‐assisted nucleation. This may be a general phenomenon that accounts for previously unexplained differences in the preferred chain alignment of confined polymer crystals.

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