Online Monitoring of Polymerization Reactions in Inverse Emulsions

Abstract

Automatic continuous online monitoring of polymerization reactions (ACOMP) was adapted to the monitoring of acrylamide polymerization in inverse emulsions. This is the first application of ACOMP to heterogeneous phase polymerization. The conversion and reduced viscosity were monitored by continuously inverting and diluting the emulsion phase using a small reactor sample stream and a breaker surfactant solution, followed by UV absorption and viscometric detection. This inversion into a stable portion of the polymer/surfactant phase diagram is accomplished in tens of seconds, yielding dilute solutions containing acrylamide (Aam), polyacrylamide (PA), oil droplets, and small quantities of surfactant, initiator and other debris, and low molecular weight compounds. After establishing the means of making ACOMP measurements, a first application of the method is made to resolving some of the kinetic issues involved in emulsion polymerization, including the evolution of molecular mass, and the simultaneous action of an "intrinsic" initiator and an added chemical initiator.

Perspectivas atuais para a obtenção controlada de polímeros e sua caracterização

“…A ACOMP e sua aplicação bem-sucedida em reações de CRP merecem uma discussão mais aprofundada que foge do objetivo deste artigo. Alb et al [29] e Mignard et al [33] trazem alguns exemplos de aplicação da ACOMP a diferentes sistemas, incluindo CRP's.…”

Online Monitoring of Copolymerization Involving Comonomers of Similar Spectral Characteristics

“…It is also noted that ACOMP has been used to monitor reactions in emulsions and inverse emulsions. 46 The ACOMP detectors included a Shimadzu PDA-20 photodiode array for full spectrum UV absorbance, a Brookhaven Instruments Corporation BI-MwA 7 angle light scattering instrument, a homebuilt single capillary viscometer, 47 a dual wavelength Shimadzu UV spectrophotometer (as a redundant cross-check on the PDA-20), and a Waters 410 RI. The delay time between withdrawal from the reactor and detection was approximately 180 s.…”

Simultaneous Monitoring of the Effects of Multiple Ionic Strengths on Properties of Copolymeric Polyelectrolytes during Their Synthesis

“…It has been used in many scenarios including free radical copolymerization [37,38], copolyelectolytes [39], branching reactions [40], emulsion [41] and inverse emulsion [42] reactions, in batch, semi-batch [43] and continuous reactors [44], for aqueous and organic solvents, for post-polymerization and derivitization reactions [45], and for the controlled radical polymerization routes nitroxide-mediated polymerization (NMP) [46], atom transfer radical polymerization (ATRP) [47], reversible addition fragmentation transfer polymerization (RAFT) [48], and ring opening metathesis polymerization (ROMP) [49]. Simultaneous monitoring of both polymer reaction characteristics and colloid size distributions (latex and monomer droplets) was also achieved in emulsion polymerization [41].…”