Initiator Feeding Policies in Semi-Batch Free Radical Polymerization: A Monte Carlo Study

Type of content
Journal Article
Thesis discipline
Degree name
Publisher
MDPI AG
Journal Title
Journal ISSN
Volume Title
Language
en
Date
2020
Authors
Seyedi A
Najafi M
Russell GT
Mohammadi Y
Vivaldo-Lima E
Penlidis A
Abstract

jats:pA Monte Carlo simulation algorithm is developed to visualize the impact of various initiator feeding policies on the kinetics of free radical polymerization. Three cases are studied: (1) general free radical polymerization using typical rate constants; (2) diffusion-controlled styrene free radical polymerization in a relatively small amount of solvent; and (3) methyl methacrylate free radical polymerization in solution. The number- and weight-average chain lengths, molecular weight distribution (MWD), and polymerization time were computed for each initiator feeding policy. The results show that a higher number of initiator shots throughout polymerization at a fixed amount of initiator significantly increases average molecular weight and broadens MWD. Similar results are also observed when most of the initiator is added at higher conversions. It is demonstrated that one can double the molecular weight of polystyrene and increase its dispersity by 50% through a four-shot instead of a single shot feeding policy. Similar behavior occurs in the case of methyl methacrylate, while the total time drops by about 5%. In addition, policies injecting initiator at high monomer conversions result in a higher unreacted initiator content in the final product. Lastly, simulation conversion-time profiles are in agreement with benchmark literature information for methyl methacrylate, which essentially validates the highly effective and flexible Monte Carlo algorithm developed in this work.</jats:p>

Description
Citation
Seyedi A, Najafi M, Russell GT, Mohammadi Y, Vivaldo-Lima E, Penlidis A Initiator Feeding Policies in Semi-Batch Free Radical Polymerization: A Monte Carlo Study. Processes. 8(10). 1291-1291.
Keywords
initiator feeding policies, styrene, methyl methacrylate, Monte Carlo simulation, polymer microstructure
Ngā upoko tukutuku/Māori subject headings
ANZSRC fields of research
Fields of Research::34 - Chemical sciences::3405 - Organic chemistry::340501 - Free radical chemistry
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