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We present a straightforward approach to well-defined 1D patchy particles utilizing crystallization-induced self-assembly. A polystyrene- block -polyethylene- block -poly(methyl methacrylate) (PS- b -PE- b -PMMA) triblock terpolymer is cocrystallized in a random fashion with a corresponding polystyrene- block -polyethylene- block -polystyrene (PS- b -PE- b -PS) triblock copolymer to yield worm-like crystalline-core micelles (wCCMs). Here, the corona composition (PMMA/PS fraction) can be easily adjusted via the amount of PS- b -PE- b -PMMA triblock terpolymer in the mixture and opens an easy access to wCCMs with tailor-made corona structures. Depending on the PMMA fraction, wCCMs with a mixed corona, spherical PMMA patches embedded in a continuous PS corona, as well as alternating PS and PMMA patches of almost equal size can be realized. Micelles prepared by cocrystallization show the same corona structure as those prepared from neat triblock terpolymers at identical corona composition. Thus, within a certain regime of desired corona compositions the laborious synthesis of new triblock terpolymers for every composition can be circumvented.

The thermo-reversible formation of wormlike micelles from a polystyrene-block-polyethylene-block-poly(methyl methacrylate) (PS-b-PE-b-PMMA) triblock terpolymer with a crystallizable middle block in organic media is presented. The formation of wormlike micelles is rather unexpected, because PE containing diblock copolymers usually form platelet-like structures. Transmission electron microscopy (TEM) investigations revealed a core−corona structure for the wormlike micelles. The core is formed by crystalline PE domains, and the soluble corona exhibits a patched structure composed of microphase-separated PS and PMMA chains. Microphase separation of the coronal chains was proven by 2D 1H nuclear Overhauser effect spectroscopy (NOESY) and TEM investigations of selectively stained samples. A combination of various techniques, such as differential scanning calorimetry (DSC), dynamic light scattering (DLS), and scanning force microscopy (SFM), indicated that the wormlike micelles might be formed by crystallization...

We present a general mechanism for the solution self-assembly of crystalline-core micelles (CCMs) from triblock copolymers bearing a semicrystalline polyethylene (PE) middle block. This approach enables the production of nanoparticles with tunable dimensions and surface structures. Depending on the quality of the solvent used for PE, either spherical or worm-like CCMs can be generated in an easy and highly selective fashion from the same triblock copolymers via crystallization-induced self-assembly upon cooling. If the triblock copolymer stays molecularly dissolved at temperatures above the crystallization temperature of the PE block, worm-like CCMs with high aspect ratios are formed by a nucleation and growth process. Their length can be conveniently controlled by varying the applied crystallization temperature. If exclusively spherical micelles with an amorphous PE core are present before crystallization, confined crystallization within the cores of the preformed micelles takes place and spherical CCMs are formed. For polystyrene-block-polyethylene-block-poly(methyl methacrylate) triblock terpolymers a patch-like microphase separation of the corona is obtained for both spherical and worm-like CCMs due to the incompatibility of the PS and PMMA blocks. The structure of the patch-like corona depends on the selectivity of the employed solvent for the PS and PMMA corona blocks, whereby nonselective solvents produce a more homogeneous patch size and distribution. Annealing of the semicrystalline PE cores results in an increasingly uniform crystallite size distribution and thus core thickness of the worm-like CCMs.