In this work, we achieved switching degradation of vinyl polymers made of a carbon–carbon bonded backbone. Crucial in this strategy was a small feed of methyl α-chloroacrylate (MCA) as the comonomer in radical polymerization of methyl methacrylate (MMA) so that the carbon–halogen bonds were introduced as the triggers for degradation. The “in-chain” trigger was activated by a one-electron redox metal catalyst as the chemical stimulus to generate the carbon-centered radical species, and subsequently, the neighboring carbon–carbon bond was cleaved via an electron transfer of the radical species giving the terminal olefin. Particularly, an iron complex (FeCl2) in conjunction with tributylamine (n-Bu3N) was effective as the chemical stimulus to allow the switching degradation, where the molecular weight was gradually decreased over time. The switching feature was confirmed by some control experiments.

Near-infrared (NIR)-responsive liquid marbles were prepared using carbon nanotube (CNT) and fullerene (C60) powders. The liquid marbles were transferred to the surface of bulk water. The liquid marbles immediately disintegrated upon NIR irradiation due to conversion of NIR energy to heat. The NIR-responsive liquid marbles can be used to induce chemical reactions, if a liquid marble containing one reactant was floated on bulk water containing another reactant. Upon NIR irradiation, the liquid marble burst and the two reactants came in contact, triggering the reaction.

Poly(dimethylsiloxane) (PDMS) surface was patterned by poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC)-containing photo-crosslinking diblock copolymers upon photo-irradiation.

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In this study, amphiphilic diblock copolymers (PMPC m -PTSM n ) composed of hydrophilic poly(2-methacryloylo xyethyl phosphorylcholine) (PMPC) and hydrophobic poly(3-(tris (trimethylsiloxy)silyl)propyl methacrylate) (PTSM) were prepared via RAFT-controlled radical polymerization. The subscripts m and n represent the degrees of polymerization of the PMPC and PTSM blocks, respectively. Thus, the m/n ratio represents the hydrophilic/hydrophobic balance of the block copolymer. We prepared PMPC m -PTSM n with m/n ratios of 12, 1.8, and 0.3 and studied their association behaviors in water. PMPC m -PTSM n with m/n ratios of 12 and 1.8 could dissolve in water. However, PMPC m -PTSM n with an m/n ratio of 0.3 did not directly dissolve in water. First, PMPC m -PTSM n with an m/n ratio of 0.3 dissolved in ethanol, whose solution was dialyzed in water to prepare the aqueous solution. The solubilizing state of these polymers in water was examined by light scattering, a fluorescence probe method, and TEM. These polymers took interpolymer aggregation state with various morphologies. The m/n ratios of 12, 1.8, and 0.3 yielded spherical shapes, cylindrical micelles, and vesicle interpolymer aggregate shapes, respectively.Polydimethylsiloxane (PDMS) is flexible and hydrophobic and is characterized by processability and low cytotoxicity. 7-10 Lowmolecular-weight siloxane surfactants are used to manufacture textiles, cosmetics, formulations, agricultural chemicals, paints, and other technologies. Amphiphilic diblock copolymers that contain siloxane groups, which act as a hydrophobic block, have been prepared in the previous studies. For example, diblock copolymers composed of hydrophilic PEO and PDMS 11,12 form spherical micelles, cylinders, and vesicles in water according to the hydrophilic/hydrophobic block chain length ratio, which is due to the hydrophobic interactions between siloxane blocks. Car et al. 13 prepared pH-responsive diblock copolymers composed of PDMS and poly(2-(dimethylamino)ethyl methacrylate) blocks and reported their pH-responsive behavior in an aqueous solution.Poly(2-(methacryloyloxy)ethyl phosphorylcholine) (PMPC) has pendant phosphorylcholine group, which is the same chemical structure as one of the polar parts of the phospholipids that constitutes the cell membrane. 14 PMPC is water-soluble polymer and the surfaces bound with the PMPC shows an excellent resistance for protein adsorption and cell adhesion. Seo et al. 15 reported the preparation of amphiphilic ABA triblock copolymers composed of PMPC as an "A" block and PDMS as a "B" block, as well as random copolymers composed of 2-(methacryloyloxy)ethyl phosphory lcholine (MPC) and 3-(tris(trimethylsiloxy)silyl)propyl methacrylate (TSM) units. ABA triblock copolymers could attach on the PDMS substrates, which are more stable than random copolymers. Since the PMPC unit located on the PDMS substrate surface, Additional supporting information may be found in the online version of this article.