Gerrit Ten Brinke

Involving supramolecular chemistry in self‐assembling block copolymer systems enables design of complex macromolecular architectures that, in turn, could lead to complex phase behavior. It is an elegant route, as complicated and sensitive synthesis techniques can be avoided. Highly grafted double‐comb diblock copolymers based on symmetric double hydrogen bond accepting poly(4‐vinylpyridine)‐block‐poly(N‐acryloylpiperidine) diblock copolymers and donating 3‐nonadecylphenol amphiphiles are realized and studied systematically by changing the molecular weight of the copolymer. Double perpendicular lamellae‐in‐lamellae are formed in all complexes, independent of the copolymer molecular weight. Temperature‐resolved measurements demonstrate that the supramolecular nature and ability to crystallize are responsible for the formation of such multiblock‐like structures. Because of these driving forces and severe plasticization of the complexes in the liquid crystalline state, this supramolecular approach can be useful for steering self‐assembly of both low‐ and high‐molecular‐weight block copolymer systems.

The formation of unusual multilayered parallel lamellae‐in‐lamellae in symmetric supramolecular double‐comb diblock copolymers is presented. While keeping the concentration of surfactant fixed, the number of internal layers was found to increase with molecular weight M up to 34 for the largest block copolymer. The number of internal structures n was established to scale as M^0.67 and therefore enables easy design of such structures with great precision.

The formation of unusual multilayered parallel lamellae‐in‐lamellae in symmetric supramolecular double‐comb diblock copolymers is presented. While keeping the concentration of surfactant fixed, the number of internal layers was found to increase with molecular weight M up to 34 for the largest block copolymer. The number of internal structures n was established to scale as M^0.67 and therefore enables easy design of such structures with great precision.

Linear poly(4-tert-butoxystyrene)-b-poly(4-vinylpyridine) (PtBOS-b-P4VP) diblock copolymers are synthesized using reversible addition–fragmentation chain transfer polymerization. The self-assembly of four different PtBOS-b-P4VP diblock copolymers is studied using small-angle X-ray scattering and transmission electron microscopy and a number of interesting observations are made. A tBOS₆₂-b-4VP₂₈ diblock copolymer with a weight fraction P4VP of 0.21 shows a disordered morphology of P4VP spheres with liquid-like short-range order despite an estimated value of of the order of 50. Increasing the length of the 4VP block to tBOS₆₂-b-4VP₁₉₉ results in a diblock copolymer with a weight fraction P4VP of 0.66. It forms a remarkably well-ordered lamellar structure. Likewise, a tBOS₁₄₆-b-4VP₁₂₀ diblock copolymer with a weight fraction P4VP of 0.33 forms an extremely well-ordered hexagonal structure of P4VP cylinders. Increasing the P4VP block of this block copolymer to tBOS₁₄₆-b-4VP₁₉₀ with a weight fraction P4VP of 0.44 results in a bicontinuous gyroid morphology despite the estimated strong segregation of . These results are discussed in terms of the architectural dissimilarity of the two monomers, characterized by the presence of the large side group of PtBOS, and the previously reported value of the interaction parameter, , for this polymer pair.

Controlled radical polymerization of 4-vinylpyridine (4VP) and N-acryloylpiperidine (API) by the RAFT process allowed preparation of well-defined double hydrogen bond accepting P4VP-b-PAPI diblock copolymers. The miscibility of this new monomer pair was studied via a random copolymer blend approach and resulted in a Flory–Huggins interaction parameter χ_4VP,API ≈ 0.03, which is higher than the commonly used styrene/MMA couple, but lower compared to styrene/isoprene. This value was found to support the bulk phase behavior of a series of diblock copolymers as evidenced by SAXS and TEM. Highly ordered structures, including cylinders, lamellae and spheres, were identified in these materials, even in diblocks of higher molecular weight and broader distribution, while a disordered morphology was indeed observed in a symmetric, low molecular weight analogue.

The phase behavior of block copolymer based supramolecular complexes polystyrene‐block‐poly(4‐vinylpyridine) (PS‐b‐P4VP) and amphiphilic pentadecylphenol (PDP) molecules resembles the phase behavior of conventional block copolymers. Several PS‐b‐P4VP(PDP) complexes are found to self‐assemble into gyroid nanostructures. Typically, the grains are randomly oriented with a maximal size of several micrometers. Here, the orientation of a gyroid PS‐b‐P4VP(PDP) complex upon shearing is reported. It is found that the (111) gyroid lattice direction orients parallel to the shear direction after only several seconds of large amplitude oscillatory shearing. Oriented gyroid complexes can be used as templates for the preparation of metal nanofoams with improved ordering with potentially superior properties. image

PVDF-based block copolymers have been employed as precursors for the construction of PVDF/PMAA/Ni nanocomposites. New poly(tert-butyl methacrylate)-block-poly(vinylidene fluoride)-block-poly(tert-butyl methacrylate) (PtBMA-b-PVDF-b-PtBMA) triblock copolymers were synthesized via atom transfer radical polymerization (ATRP) of tBMA from chlorine-terminated PVDF macroinitiators. The alternating crystalline–amorphous lamellar nanostructure and the spherulitic microstructure indicate the dominant role of crystallization of the PVDF segments during structure formation. The polar β-crystalline phase of PVDF has been detected within the block copolymer films. Hydrolysis of the tBMA segments and subsequent backfilling of the remaining polymer template with nickel through electroless metal deposition generated PVDF/PMAA/Ni nanocomposites. The β-polymorph was preserved during hydrolysis and electroless plating, as well as the lamellar morphology.