| Abstract
| - To probe the effect of junction point functionality in miktoarm star block copolymerarchitecture on chain conformation and morphology, a series of AnBn miktoarm star copolymers where Aarms are PS blocks and B arms are PI blocks were investigated. The overall series including a diblockand the star block copolymers can be represented by AnBn, where n = 1, 2, 4, and 16. These materialswere produced by synthesizing a single batch of living PS arms and a single batch of living PI arms andthen linking them together with chlorosilane coupling agents of different functionality. Thus, all PS armsare identical and all PI arms are identical across the entire series of materials. All stars in the serieshave equal numbers of PS and PI arms, and the volume fractions of all the samples in the series (nearly0.50 PS by volume) are identical within experimental error. All the materials were found, via small-angle X-ray scattering and transmission electron microscopy, to form lamellar morphologies. A significantincrease in lamellar spacing with increasing junction point functionality (n) was found in this series ofmaterials and can be attributed to molecular crowding near the junction point.
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