An easy technique is developed to fabricate highly conductive and reflective double-surface-silvered polyimide films at room temperature by the incorporation of silver ions in surface-modified polyimide, and subsequently by the in situ reduction of silver ions in alkaline containing aqueous glucose solution. Surface properties of the silvered composite films were investigated as a function of treatment time and reducing environment, respectively. Sheet reflectivity and conductivity can be controlled by adjusting the potassium hydroxide (KOH) etching and reducing conditions. The excellent silver-polymer adhesive property is based on a "tree roots" like micro/nanostructure of the silver layers. The essential mechanical properties of the silvered films were maintained as their inside matrix is intact during the whole procedure. Different properties between one film's double-side surfaces were investigated during the fabricating process. Films were characterized by inductively coupled plasma (ICP), X-ray diffraction (XRD), contact angle (CA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), four point probe instrument, and ultraviolet (UV) spectrophotometer.

Although linear block copolymer assemblies derived from polymerization-induced self-assembly (PISA) have been prepared with a wide variety of structures, examples with hyperbranched block copolymer assemblies have remained elusive. In this work, efficient synthesis and self-assembly of segmented hyperbranched block copolymers (SHBCs) were achieved via reversible addition–fragmentation chain-transfer (RAFT)-mediated dispersion polymerization-induced self-assembly (PISA) using segmented hyperbranched macro-RAFT agents. Two different approaches including the R-RAFT approach and the Z-RAFT approach were employed to synthesize SHBCs with an important structural difference. Using the Z-RAFT approach, the solvophobic block always grows in the inner of SHBCs, allowing the efficient synthesis of colloidally stable SHBC assemblies with a variety of morphologies. Finally, further structural control over SHBCs and morphological control over SHBC assemblies were achieved by combining the R-RAFT approach and the Z-RAFT approach or adding a chain-transfer monomer into the RAFT-mediated PISA. This work not only develops a facile method for the efficient synthesis of SHBCs and SHBC assemblies but also provides important insights into the PISA process of nonlinear block copolymers.

Bottlebrush polymers exhibiting unique properties have attracted considerable attention for applications in many research areas. Herein, the first simultaneous synthesis and self‐assembly of bottlebrush block copolymers at room temperature via photoinitiated polymerization‐induced self‐assembly (photo‐PISA) using multifunctional macromolecular chain transfer agents (macro‐CTAs) is reported. Comparing with linear block copolymers, the bottlebrush block copolymers can promote the formation of higher‐order morphologies (e.g., vesicles) when targeting similar degrees of polymerization (DPs). Moreover, a higher polymerization rate is observed in the case of bottlebrush block copolymers. Gel permeation chromatography (GPC) analysis shows that good polymerization control is maintained when synthesizing bottlebrush block copolymers by photo‐PISA. Finally, the obtained bottlebrush block copolymer vesicles are used as seeds for further chain extension and multicompartment nanoparticles with a sponge internal structure are formed. It is expected that this study will not only expand polymer architectures employed in PISA, but also provide a new strategy to synthesize polymer nanoparticles with unique structures.

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Although reversible addition−fragmentation chain transfer (RAFT) dispersion polymerization-induced self-assembly (PISA) has become one of the most attractive methods for the synthesis block copolymer assemblies, the synthesis of well-defined graft copolymer assemblies has rarely been reported. Herein, multifunctional macro-RAFT agents with well-defined structures were synthesized by green light-activated photoiniferter RAFT polymerization and subsequently used in RAFT dispersion polymerization for the synthesis of graft copolymers as well as graft copolymer assemblies. A direct comparison between RAFT-PISA behaviors of linear block copolymers and graft copolymers was conducted by using a monofunctional macro-RAFT agent and a multifunctional macro-RAFT agent, respectively. Transmission electron microscopy (TEM) analysis demonstrated that the structure of graft copolymers facilitated the creation of polymer nanoparticles with higher-order morphologies. Multifunctional macro-RAFT agents with different distributions of RAFT groups were also synthesized via a two-step photoiniferter RAFT polymerization. The influence of the distribution of solvophobic side chains on the RAFT-PISA process as well as graft copolymer assemblies was also investigated. We anticipate that this work should not only shed some light on the synthesis of well-defined graft copolymers and graft copolymer assemblies but also be useful to understand the mechanism RAFT-PISA of graft copolymers.

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