Stochastic modeling constitutes a powerful technique to obtain complete distributions of microstructural properties of polymer materials and may help to synthesize polymers with well-defined microstructure, as in the case of controlled radical polymerizations (CRP). However, these techniques have been often applied to describe polymerizations performed in batch or idealized continuous plug flow conditions. The present manuscript describes a Monte Carlo technique that can be used to calculate microstructural properties in polymerization systems performed continuously with arbitrary residence time distributions (RTD), under regime of complete micromixing segregation. The technique approximates the continuous system by a set of batch reactors, operated independently, whose volumes and batch times can be related to the discretized version of the RTD. The technique is applied successfully to describe a styrene-based CRP reaction carried out in an ideal continuous stirred tank reactor and a tubular non-ideal tubular reactor.

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Polymer materials are normally constituted by chains of different sizes and compositions due to the stochastic nature of most polymerization mechanisms. For this reason, dissipative particle dynamics (DPD) simulations are carried out in the present work to investigate the effect of chain length distribution (CLD), chemical composition distribution (CCD), and block length distribution (BLD) on the process of self‐assembly of diblock copolymers. Flory and Poisson distributions are used to study CLD and BLD effects and bidispersed distributions are used for the study of CCD effects. Visual inspection and the static structure factor S(q) are used to evaluate the obtained structures. The results show that high dispersion in the CCD and different levels of dispersion in the BLDs of different components of the system increase the sizes of the segregated domains and decisively affect the structure and the purity of the formed mesophases.

Blends prepared by mixing incompatible homopolymers with a compatibilizing copolymer attract high technological interest due to their self‐assembling behavior. In the present work, 281 dissipative particle dynamics (DPD) simulations are performed in order to evaluate the influence of copolymer microstructure and concentration on properties of these systems. The results show that alternate copolymers are arranged between the homopolymeric phases while nanodomains rich in each of the components are formed in the copolymeric matrix. Dispersion in block lengths increases the size of these nanodomains, so that they can properly allocate homopolymer chains. Besides, dispersions in chain lengths and chemical compositions of diblock copolymers, which can form self‐assembled mesostructures, also lead to development of larger mesophase domains. Larger dispersions of chain lengths and chemical compositions cause the increase of the amount of copolymers necessary to bring about changes in the mixing behavior, when compared to non‐dispersed copolymers. It can be concluded that microstructural properties of the copolymer exert a decisive impact on molecular interactions and, consequently, on the characteristics of the mesophases generated during the blending process. Therefore, microstructure control methods, stemming from both polymer‐reaction engineering and polymer‐purification techniques, are important for the design and resulting performance of the analyzed blends.