Stapler Strategies for Upcycling Mixed Plastics.

Mechanical recycling is one of the simplest and most economical strategies to address ever-increasing plastic pollution, but it cannot be applied to immiscible mixed plastics and suffers from property deterioration after each cycle. By combining the amphiphilic block copolymer strategy and reactive compatibilization strategy, we designed a series of stapler strategies for compatibilizing/upcycling mixed plastics. First, various functionalized graft copolymers were accessed via different synthetic routes.

Polymer Multi-Block and Multi-Block Strategies for the Upcycling of Mixed Polyolefins and Other Plastics.

Due to a continued rise in the production and use of plastic products, their end-of-life pollution has become a pressing global issue. One of the biggest challenges in plastics recycling is the separation of different polymers. Multi-block copolymers (MBCPs) represent an efficient strategy for the upcycling of mixed plastics via induced compatibilization, but this approach is limited by difficulties associated with synthesis and structural modification.

A new turn on coumarin-based fluorescence probe for Cr detection in aqueous solution.

Isatin-3-(7'-Methoxychromone-3'-methylidene) hydrazone (L) was synthesized based on chromone schiff base, and used to construct a novel sensor to detect Cr. Fluorescence detection experiments were carried out for a range of different concentrations of Cr in aqueous solutions. A concentration calculation model was built on the basis of eliminating interference of excitation spectrum in the fluorescence spectra with mathematical method.

A co-anchoring strategy for the synthesis of polar bimodal polyethylene.

Since polar groups can poison the metal centers in catalysts, the incorporation of polar comonomers usually comes at the expense of catalytic activity and polymer molecular weight. In this contribution, we demonstrate polar bimodal polyethylene as a potential solution to this trade-off. The more-polar/more-branched low-molecular-weight fraction provides polarity and processability, while the less-polar/less-branched high-molecular-weight fraction provides mechanical and melt properties.

A Cocatalyst Strategy to Enhance Ruthenium-Mediated Metathesis Reactivity towards Electron-Deficient Substrates.

Ruthenium-mediated olefin metathesis has been widely applied for the synthesis of various organic molecules and polymers. Inspired by the cocatalyst strategy for olefin polymerization, here we demonstrate that the abstraction of a chloride ion from various commercially available ruthenium catalysts significantly enhances their reactivity towards electron-deficient internal olefins. This cocatalyst strategy can be implemented in ethenolysis and cross-metathesis reactions of FG-CH=CH-FG type substrates bearing electron-withdrawing groups and the synthesis of telechelic polymers that can be converted to polyethylene-like materials with closed-loop recycling properties.

A general strategy for heterogenizing olefin polymerization catalysts and the synthesis of polyolefins and composites.

The heterogenization of homogeneous metal complexes on solid supports presents an efficient strategy for bridging homogeneous catalysts with industrially-preferred heterogeneous catalysts; however, a series of drawbacks restrict their implementation in olefin polymerization, particularly for copolymerization with polar comonomers. In this contribution, we report an ionic anchoring strategy that is highly versatile, generally applicable to different systems, and enables strong catalyst-support interactions while tolerating various polar functional groups. In addition to greatly enhanced polymerization properties, the supported catalysts achieved higher comonomer incorporation than their unsupported counterparts.