Abstract
Block copolymers are of increasing interest because of their nanometer-scale morphologies, which can be utilized in a range of applications, including nanolithography. Orientation of the domains can be controlled by part design and processing conditions in injection molding. In this work the surface morphology and alignment of block copolymers by mechanical flow fields from injection molding was investigated using a styrene-ethylene/butylene-styrene triblock copolymer (SEBS) and compared with the morphology induced by spin coating. Compared with the isotropic morphology found by spin coating and annealing, the surface domains were oriented in the flow direction. Increasing mold temperature and injection velocity enhanced the degree of orientation, whereas melt temperature had little effect. Smaller characteristic lengths were produced with higher mold temperatures and injection velocities.
| Original language | English |
|---|---|
| Pages (from-to) | 5837-5845 |
| Number of pages | 9 |
| Journal | Polymer |
| Volume | 50 |
| Issue number | 24 |
| DOIs | |
| State | Published - Nov 16 2009 |
| Externally published | Yes |
Funding
The authors would like to thank the support of the National Science Foundation (Award # NSF-0425826). The authors wish to thank Kraton, Inc. for the SEBS material and Nissei America for the injection molding machine.
Keywords
- Block copolymer
- Injection molding
- Surface morphology orientation