Conjugation through Si-O-Si bonds, silsesquioxane (SQ) half cage copolymers, extended examples SiO/SiO units: multiple emissive states in violation of Kasha's rule.

We previously reported that phenyl- and vinyl-silsesquioxanes (SQs), [RSiO] (R = Ph or vinyl) functionalized with three or more conjugated moieties show red-shifted absorption- and emission features suggesting 3-D conjugation a cage centered LUMOs. Corner missing [PhSiO](OSiMe) and edge opened, end capped [PhSiO](OSiMe) (double decker, DD) analogs also offer red shifted spectra again indicating 3-D conjugation and a cage centered LUMO. Copolymerization of DD [PhSiO](OSiMevinyl) with multiple R-Ar-Br gives copolymers with emission red-shifts that change with degree of polymerization (DP), exhibit charge transfer to FTNCQ and terpolymer averaged red-shifts suggesting through chain conjugation even with two (O-Si-O) end caps possibly a cage centered LUMO.

Efficient Depolymerization of Glass Fiber Reinforced PET Composites.

The transition to an eco-friendly circular materials system for garbage collected after use from end-users is a serious matter of concern for current society. One important tool in this challenge to achieve a truly circular economy is the chemical recycling of polymers. It has previously been demonstrated that chemical recycling is a feasible alternative to reach carbon circularity, which promotes the maximization of carbon recovery through all possible means.

Ultrafast Simultaneous and Selective Depolymerization of Heterogeneous Streams of Polyethylene Terephthalate and Polycarbonate: Towards Industrially Feasible Chemical Recycling.

Mixed plastic waste-streams are a main obstacle to a more extensive implementation of polymer recycling. Separating mixed-plastic waste streams demands time and effort at collection or in the recycling plant, while many products consist of multiple polymers that cannot be readily separated. Chemical recycling could provide the key to overcome this issue by targeting specific chemical bonds, enabling selective depolymerization of a single polymer class in a mixture.

Influence of Phyllosilicate Structure on Performance of Polypropylene Nanocomposites Prepared via Polymerization.

This work explores the use of two different phyllosilicate structures (muscovite mica and bentonite) as co-support for polymerization of propylene using Ziegler-Natta catalyst based on MgCl₂/TiCl₄ with electron donor for isotacticity control. It was observed along the experiments that the mass ratio MgCl₂:mica needs to be at least 3:1 in order to maintain a feasible catalyst activity. It was found through XRD, TEM, SEM and DMA that crystallinity of polypropylene composites is different according to the nature of phyllosilicates used and the mechanical performance of mica composites, as long as wettability and thermal stability were in general higher than those of PP/bentonite composites.