Mechanochemical tuning of molecular weight distribution of styrene homopolymers as postpolymerization modification in solvent‐free solid‐state

Abstract

Mechanochemical degradation by planetary ball milling (PM) is used for postpolymerization modification of styrene homopolymers (PS). A complete factorial design was chosen to study the effect of radical scavengers, milling time, initial molecular weight, and revolution radius (R p), on the shape of molecular weight distributions (MWDs) of PS. Size-exclusion chromatography analysis shows the feasibility of fine-tuning MWD of PS at up to 40% conversion. Distributions ranged from unimodal to bimodal in a PM with R p = 150 mm at different stage of milling, whereas in a PM with R p of 60.8 mm the adjustment of unimodal distributions is achieved. Initial polydispersity is more important to develop bimodal distributions when compared with initial molecular weight. Fourier transform infrared and X-ray electron spectrometry analysis show some suppression of PS degradation and complete oxidation inhibition of macromolecular radicals with the incorporation of radical scavengers, which we considered as additional aids when adjusting the MWDs.

Mechanochemically accessing a challenging-to-synthesize depolymerizable polymer

“…While ball milling has been extensively applied to mechanochemically degrade commercial polymers [38][39][40][41][42] , such as polystyrene, poly (ethylene terephthalate), and epoxy resin, its use in the context of Article https://doi.org/10.1038/s41467-023-35925-2 mechanophore activation is rare. To test the feasibility of activating the mechanophore through ball mill grinding, the film PN1 was subjected to ball milling (25 Hz, 10 min) followed by depolymerization (2 mol% G2, CDCl 3 , 30 °C, 16 h).…”

Force ahead: Emerging Applications and Opportunities of Polymer Mechanochemistry

“…4 Specifically, researchers within the mechanochemical trituration community investigated ball milling processes for sustainable polymer syntheses, 4 postsynthetic modification, 37 or tuning of molar mass distributions. 38 Notably, this line of research might lead to a convergence of the methods of trituration and polymer mechanochemistry.…”

“…Exploiting mechanical force to initiate a bond formation reaction can reach far beyond repair and healing functions, as Kim, Borchardt, and co-workers succinctly summarized . Specifically, researchers within the mechanochemical trituration community investigated ball milling processes for sustainable polymer syntheses, postsynthetic modification, or tuning of molar mass distributions . Notably, this line of research might lead to a convergence of the methods of trituration and polymer mechanochemistry.…”