Affiliation:
1. MIREA – Russian Technological University (M.V. Lomonosov Institute of Fine Chemical Technologies)
2. JSC «Academician V.A. Kargin Research Institute of Chemistry and Technology of Polymers with a Pilot Plant»
3. Lomonosov Moscow State University
Abstract
The dispersion composition of polymer suspensions and molecular weights of polymers obtained by suspension polymerization of MMA in the presence of polymer surfactants – methylmethacrylate and methacrylic acid copolymers – were studied. It is shown that a highly dispersed fraction of particles with diameters of 0.02–2.0 µm and a fraction of particles with large diameters (up to 1000 µm) are always present in the polymer suspension. After fractionation of polymer suspensions 3 fractions of particles with different diameters were obtained. For each particle fraction the molecular masses of polymers were determined by viscometry. A significant difference in the values of the molecular masses of polymers obtained as particles of small and large diameters – 105 and 106 Da, respectively – is shown. The presence of a highly dispersed fraction of particles in which a polymer of high molecular weight is formed has a noticeable effect on the average molecular weight of the polymer. In particles of small diameter polymerization takes place according to a mechanism close to the emulsion, due to the fact that the volume of such particles contains a small amount of radicals. The high rate of polymerization leads to the formation of a polymer of high molecular weight, the appearance of a gel effect and a decrease in the termination constant. In most particles, polymerization proceeds by a mechanism close to the solution polymerization, and polymers of low molecular weight are formed. This makes it possible to synthesize polymers of a given molecular weight in drops of certain dispersity.
Reference16 articles.
1. Jahanzad F., Sajjadi S., Yianneskisb M., Brooks B.W. In situ mass-suspension polymerization. Chem. Eng. Sci. 2008; 63:4412-4417.
2. Tuchigami K., Taguchi Y., Tanaka M. Synthesis of calcium carbonate vaterite crystals and their effect on stabilization of suspension polymerization of MMA // Advanced Powder Technology. 2009; 20:74-79.
3. Ze Xie, Qi Ziu, Zheng-Hong Luo. A multiscale CFDPBM coupled model for kinetic and liquid-liquid dispersion behavior in suspension polymerization stirred tank. Chem. Ing. Res. and Design. 2018; 130:1-17.
4. Fitch R.M., Tsai C.H. Particle formation in polymer colloids. III. Prediction of the number of particles by a homogeneous nucleation theory. In: Polymer Colloids. New York, 1971: 73-102.
5. Mahdavian A.R., Abdollahi M. Investigation into the effect of carboxylic acid monomer on particle nucleation and growth in emulsifier-free emulsion copolymerization of styrene, butadiene and acrylic acid. Polymer. 2004; 45:3233-3239.
Cited by
1 articles.
订阅此论文施引文献
订阅此论文施引文献，注册后可以免费订阅5篇论文的施引文献，订阅后可以查看论文全部施引文献