low comonomer reactivity ratio and produces high-crystallinity blocks (hard-blocks), while the other catalyst has high comonomer reactivity ratio and makes low-crystallinity blocks (soft-blocks). The CSA is the special component because it shuttles living polymer chains between the two catalysts, making chains with alternating hard and soft blocks. [1][2][3][4][5][6][7] OBCs have higher heat and abrasion resistances, and better processability than conventional polyolefin elastomers. [8][9][10][11] Because OBC may have many blocks, mathematical models are needed to quantify how polymerization conditions affect their microstructures. A detailed mathematical model describes how the complex OBC microstructure evolves during polymerization, providing useful insights on how to control these microstructures. Models for chain-shuttling polymerization in continuous stirred-tank reactors (CSTRs) were first developed using the method of moments to describe polymerization kinetics and average chain microstructures. [12,13] Because this approach cannot generate detailed microstructural distributions, Monte Carlo (MC) models were later developed for OBCs made in CSTRs operated at steadystate. [14][15][16] Subsequently, Mohammadi et al. developed Chain-shuttling polymerization with dual catalysts has introduced a new class of polyolefins called olefin block copolymers (OBCs). A dynamic Monte Carlo model to describe the kinetics of chain-shuttling copolymerization in a semi-batch reactor is developed, and used it to study how the microstructure of OBCs with different numbers of blocks per chain evolves during polymerization. The model also describes how chain-shuttling rate constants and concentration of chain-shuttling agent affect populations of OBCs with different numbers of blocks per chain. These model predictions are useful to make OBCs with precisely designed microstructures.

5-hydroxymethylfurfural (5-HMF) is one of the key bio-based platform chemicals for the production of high-value chemicals and fuels. The conventional production of 5-HMF from biomass is confronted by the relatively low yield and high production cost. In this work, the enhancement of a continuous catalytic synthesis of 5-HMF in a biphasic-dispersed flow reactor was proposed. Glucose, hydrochloric acid, and methyl isobutyl ketone (MIBK) were used as a low-cost raw material, catalyst, and organic solvent, respectively. The main factors (reaction temperature, residence time, solvent amount, and catalyst concentration) affecting the yield and selectivity of 5-HMF were studied. The 5-HMF yield of 81.7% and 5-HMF selectivity of 89.8% were achieved at the residence time of 3 min, reaction temperature of 180 • C, the volumetric flow rate of aqueous phase to organic phase of 0.5:1, and catalyst concentration of 0.15 M. The yield and selectivity of 5-HMF obtained from the biphasic system were significantly higher than that obtained from the single phase system. The superior 5-HMF production in our system in terms of operating conditions was presented when compared to the literature data. Furthermore, the continuous process for removing HCl from the aqueous product was also proposed.

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Living ethylene/1‐olefin copolymerization with multiple comonomer feeding stages allows the production of living block copolymers (LBCs) with well‐controlled microstructures. A dynamic Monte Carlo model is developed to simulate the production of LBCs in a semibatch reactor, and it is used to study how the polymer microstructure evolves during the polymerization. The model also describes how chain transfer reactions affect the microstructure of LBC blocks. These model predictions provide useful guidelines for producing LBCs with precisely designed microstructures.