A quantitative treatment of particle size distributions in emulsion polymerization

Abstract

SynopsisA quantitative analysis is presented for predicting the particle size distributions obtained in emulsion polymerization. The results obtained are compared with experimental data in terms of the particle-size-distribution curves as well as the statistical parameters of the distributions. Comparisons are made for changes in initiator level, surfactant level, water:monomer ratio, and temperature. The manner in which these variables change the distributions and the reasons for these changes are identified. The distribution of radicals among particles of different sizes is seen to be significant. Large particles are expected to contain a greater number of radicals per particle than the smaller ones in the same latex. The effects of such a radical distribution upon the properties of the latex are discussed.

Control of emulsion polymerization reactors

“…Discussion on population balances can be found in Hulburt and Katz (1964), Randolph (1964), and Ramkrishna (1985). Population balances have been used in modeling the PSD in emulsion polymerization by several investigators (Nomura et al, 1971;Sundberg and Eliassen, 1971;Stevens and Funderburk, 1972;Min and Ray, 1974;Thompson and Stevens, 1977;Kirillov and Ray, 1978;Cauley et al, 1978;Min and Ray, 1978;Min and Gostin, 1979;Sundberg, 1979;Gilbert et al, 1984;Rawlings and Ray, 1988).…”

“…In a subsequent publication Sundberg (1979) discusses in more detail this attempt including additional information and conclusions. The author reports that both the mean and standard deviation of the PSD decrease as the initiator increases and that all curves obtained are skewed toward the smallest particle size.…”

Dynamic modeling of emulsion polymerization reactors

“…Of course, decisions must be made on the relative importance of the various phenomena occurring in a particular system. Other, more recent efforts on the modeling of emulsion reactors include: the dynamic modeling of a continuous stirred tank reactor (CSTR) for a general polymer system using a population balance approach (Thompson and Stevens, 1977); the dynamic and steady state modeling of a methyl methacrylate (MMA) CSTR using a population balance (Kirillov and Ray, 1978); the study of a general continuous emulsion system using population balances (Cauley et al, 1978); the modeling of a batch MMA reactor (Min and Ray, 1978); the population balance approach to a general continuous polymer system (Sundberg, 1979); the age distribution analysis approach to a continuous vinyl acetate (VAc) system (Kiparissides et al, 1979;Chiang and Thompson, 1979); the population balance modeling of a semibatch poly(viny1 chloride) (PVC) reactor (Min and Gostin, 1979); the dynamic modeling of a MMA CSTR using monodispersed approximation models (Schork et al, 1980); the simulation of a batch styrene (STY) reactor (Kiparissides and Ponnuswamy, 1981), and of a STY and a MMA reactor (Cauley and Thompson, 1982), and the discussion of PSD evolution (Lichti et al, 1981(Lichti et al, , 1983Gilbert and Napper, 1983;Gilbert et al, 1984); the description of a typical emulsion copolymerization system (Ballard et al, 1981); the study of batch and continuous VAc latex reactors (Penlidis et al, 1984;Pollock et al, 1981, respectively); the simulation of a STY emulsion reactor (Bataille et al, 1982); the dynamic modeling of the batch and continuous emulsion polymerization of vinyl chloride (Penlidis et al, 1984); and the steady state and dynamic modeling of both batch and continuous reactors for styrene-butadiene rubber (SBR) using both "monodispersed approximation" and population balance models (Hoffman, 1981;Hamielec et al, 1983;Broadhead, 1984;Broadhead et al, 1984).…”

Emulsion polymerization: Theory of particle size distribution in copolymerization system

“…Then eq. (10) is divided into the time-derivative, absorption, desorption, termination and rAB -TBA terms. Each of these terms is reduced separately.…”