Coagulative Nucleation in the Copolymerization of Methyl Methacrylate–Butyl Acrylate under Monomer-Starved Conditions
Sujey G. Castellanos,
V. Vladimir A. Fernández-Escamilla,
Miguel Á. Corona-Rivera,
Karla J. González-Iñiguez,
Arturo Barrera,
Francisco J. Moscoso-Sánchez,
Edgar B. Figueroa-Ochoa,
Israel Ceja,
Martín Rabelero,
Jacobo Aguilar
Affiliations
Sujey G. Castellanos
Departamento de Ciencias Tecnológicas, Centro Universitario de la Ciénega, Universidad de Guadalajara, Av. Universidad No. 1115, Col. Lindavista, Ocotlán 47819, Mexico
V. Vladimir A. Fernández-Escamilla
Departamento de Ciencias Tecnológicas, Centro Universitario de la Ciénega, Universidad de Guadalajara, Av. Universidad No. 1115, Col. Lindavista, Ocotlán 47819, Mexico
Miguel Á. Corona-Rivera
Ingeniería Química, Coordinación Académica Región Altiplano (COARA), Universidad Autónoma de San Luis Potosí, Carretera a Cedral Km 5+600, San Jose de las Trojes, Matehuala 78700, Mexico
Karla J. González-Iñiguez
Departamento de Química, Centro Universitario de Ciencias Exactas en Ingenierías, Universidad de Guadalajara, Blvd. Gral. Marcelino García Barragán No. 1421, Col. Olímpica, Guadalajara 44430, Mexico
Arturo Barrera
Departamento de Ciencias Tecnológicas, Centro Universitario de la Ciénega, Universidad de Guadalajara, Av. Universidad No. 1115, Col. Lindavista, Ocotlán 47819, Mexico
Francisco J. Moscoso-Sánchez
Departamento de Química, Centro Universitario de Ciencias Exactas en Ingenierías, Universidad de Guadalajara, Blvd. Gral. Marcelino García Barragán No. 1421, Col. Olímpica, Guadalajara 44430, Mexico
Edgar B. Figueroa-Ochoa
Departamento de Química, Centro Universitario de Ciencias Exactas en Ingenierías, Universidad de Guadalajara, Blvd. Gral. Marcelino García Barragán No. 1421, Col. Olímpica, Guadalajara 44430, Mexico
Israel Ceja
Departamento de Física, Centro Universitario de Ciencias Exactas en Ingenierías, Universidad de Guadalajara, Blvd. Gral. Marcelino García Barragán No. 1421, Col. Olímpica, Guadalajara 44430, Mexico
Martín Rabelero
Departamento de Ingeniería Química, Centro Universitario de Ciencias Exactas en Ingenierías, Universidad de Guadalajara, Blvd. Gral. Marcelino García Barragán No. 1421, Col. Olímpica, Guadalajara 44430, Mexico
Jacobo Aguilar
Departamento de Ciencias Tecnológicas, Centro Universitario de la Ciénega, Universidad de Guadalajara, Av. Universidad No. 1115, Col. Lindavista, Ocotlán 47819, Mexico
Coagulative nucleation in the copolymerization of methyl methacrylate–butyl acrylate (MMA-BA) via semicontinuous emulsion heterophase polymerization (SEHP) under monomer-starved conditions in latexes with high solid content (50.0 wt %) and low concentrations of surfactant is reported. The SEHP technique allows the obtention of latex with high colloidal stability and has potential industrial application in polymer synthesis. High instantaneous conversions (>90%) and a high-ratio polymerization rate/addition rate (Rp/Ra) ≥ 0.9 were obtained at low times until the final copolymerization, which confirmed the starved conditions in the systems at the highest surfactant concentrations. The particle size exhibited a linear size increment at conversions between 0 and 40% induced by homogeneous nucleation, a transition region between 40 and 50%, and non-linear behavior at higher conversions by coagulative nucleation. These three behaviors were also observed in the particle surfactant coverage area (Sc), Z-potential, particle coagulation rate (dNp/dt) by the Smoluchowski model, final particle size (Dpz), and number particle (Np) through the reaction. By means of transmission electron microscopy (TEM) images, the onset of coagulation was observed from 50% of conversion until the end of the reaction. In addition, in both processes of copolymerization, tacticity was displayed (mainly syndiotacticity).