Cleavable Comonomers for Chemically Recyclable Polystyrene: A General Approach to Vinyl Polymer Circularity was written by Kiel, Gavin R.;Lundberg, David J.;Prince, Elisabeth;Husted, Keith E. L.;Johnson, Alayna M.;Lensch, Valerie;Li, Sipei;Shieh, Peyton;Johnson, Jeremiah A.. And the article was included in Journal of the American Chemical Society in 2022.Application In Synthesis of Methyl 2-bromo-4-fluorobenzoate This article mentions the following:
Many common polymers, especially vinyl polymers, are inherently difficult to chem. recycle and are environmentally persistent. The introduction of low levels of cleavable comonomer additives into existing vinyl polymerization processes could facilitate the production of chem. deconstructable and recyclable variants with otherwise equivalent properties. Here, we report thionolactones that serve as cleavable comonomer additives for the chem. deconstruction and recycling of vinyl polymers prepared through free radical polymerization, using polystyrene (PS) as a model example. Deconstructable PS of different molar masses (~20-300 kDa) bearing varied amounts of statistically incorporated thioester backbone linkages (2.5-55 mol %) can be selectively depolymerized to yield well-defined thiol-terminated fragments (<10 kDa) that are suitable for oxidative repolymn. to generate recycled PS of nearly identical molar mass to the parent material, in good yields (80-95%). A theor. model is provided to generalize this molar mass memory effect. Notably, the thermomech. properties of deconstructable PS bearing 2.5 mol % of cleavable linkages and its recycled product are similar to those of virgin PS. The additives were also shown to be effective for deconstruction of a cross-linked styrenic copolymer and deconstruction and repolymn. of a polyacrylate, suggesting that cleavable comonomers may offer a general approach toward circularity of many vinyl (co)polymers. In the experiment, the researchers used many compounds, for example, Methyl 2-bromo-4-fluorobenzoate (cas: 653-92-9Application In Synthesis of Methyl 2-bromo-4-fluorobenzoate).
Methyl 2-bromo-4-fluorobenzoate (cas: 653-92-9) belongs to organobromine compounds. Many of the organo bromine compounds are relatively nonpolar. Bromine is more electronegative than carbon (2.8 vs 2.5) and hence the carbon in a carbon–bromine bond is electrophilic in nature. In the pharmaceutical industry organo bromine derivatives are used as sedatives, vasodilators, antiseptic agents, and anticancer agents.Application In Synthesis of Methyl 2-bromo-4-fluorobenzoate
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary