The self-assembly of bottlebrush block polymers into a lamellar phase was investigated using a combination of experiment and self-consistent field theory (SCFT). Nine diblock bottlebrush polymers were synthesized with atactic polypropylene side chains (block A) and polystyrene side chains (block B) attached to poly(norbornene) backbones of various contour lengths, L, and the resulting lamellar structures were analyzed using small-angle X-ray scattering. The scaling of the lamellar period, d0 ∼ L(γ), exhibited an increasing exponent from γ ≈ 0.
View Article and Find Full Text PDFA series of bottlebrush polymers with atactic polypropylene side chains were synthesized via ring-opening metathesis polymerization using Grubbs' third-generation catalyst (HIMes)(3-BrPy)(Cl)Ru═CHPh. Polymers were prepared with fixed side chain length and variable backbone degree of polymerization (DP) ranging from 11 to 732 ( = 22-1500 kg/mol) and include the largest reported polyolefin-based bottlebrush polymers. The zero-shear viscosity of each polymer sample was measured using small-amplitude oscillatory shear measurements.
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