Abstract Despite its potential in the production of polymers from renewable sources, D-limonene faces difficulties in its polymerization, resulting in low monomer conversion and molar mass. In order to investigate the non-ideality inherent kinetics, this work explores different modeling strategies for D-limonene radical polymerization, using benzoyl peroxide as initiator. The starting model considered the classical approach for conventional radical polymerization. This model was then corrected by including reaction orders different from the unit. After an analysis and choice of the best model, computer simulations were compared with experimental results from literature, validating the chosen approach. It was found that the process is drastically influenced by chain transfer reactions, presenting a non-ideal behavior. Finally, an analysis of distinct reaction conditions provided information on monomer conversion, molar mass and polymer dispersity, which could guide future research in the synthesis optimization. Higher molar mass poly(limonene) were obtained by simultaneously reducing the monomer and initiator concentrations.

Block copolymers based on tert-butyl methacrylate (tBMA) have many uses, such as thermo‐responsive polymers, amphiphilic copolymers, and many applications in the medical field. Atom-transfer radical polymerization (ATRP) is the main technique to produce these controlled macromolecular architectures. This paper provides a simplified kinetic modeling and computational study of tBMA ATRP. The main objective is to understand the behavior of chemical species in the reaction and its influence on polymer properties (molecular weight and dispersity). The proposed model presented good reproducibility of the experimental data, with average errors less than 10%. The simulations indicated a strong initiator and catalyst concentration dependence on the monomer conversion. Although the highest initiator proportion induced a dispersity increase in conversions less than 20%, in general, for tBMA ATRP, the range of operational condition cannot affect dispersity directly. In addition, our finds about the effect of Keq on polymer properties indicated that to conduct the reaction using catalyst systems with Keq around 10-5 - 10-6 would provide very low dispersity polymers in a fast reaction time.

Abstract This paper uses a new kinetic modeling and simulations to analyse the effect of temperature on the polystyrene properties obtained by atom-transfer radical polymerization (ATRP). Differently from what has been traditionaly published in ATRP modeling works, it was considered “break” reactions in the mechanism aiming to reproduce the process at high temperatures. Results suggest that there is an upper limit temperature (130 °C), above which the polymer architecture loses the control. In addition, for the system considered in this work, the optimum operating temperature was 100 °C, because at this temperature polymer with very low polydispersity index is obtained, at considerable fast polymerization rate. Therefore, this present paper provides not only a tool to study ATRP processes by simulations, but also a tool for analysis and optimization, being a basis for future works dealing with this monomer and process.