The production of rubber‐modified polystyrene. I. Rheological behavior of the polymerizing system

Abstract

SynopsisThe rheological behavior of the two-phase systems consisting of a polystyrene-irtstyrene phase distributed in a rubber-in-styrene phase is shown to exhibit increasing IIOIINewtouiari behavior up to the phase inversion point, as a consequence of its two phase nature. The equation is recommended for the prediction of the viscosity of the polymerizing mass up to phase inversion during the production of HIPS by the in situ bulk polymerization of styrene in the presence of dissolved rubber.

Polystyrene grafted onto high-cis-1,4 polybutadiene backbone via 'living' radical polymerization with 2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO) radical

“…The continuous phase is now the PS phase dissolved in styrene/ethylbenzene and the dispersed phase is composed of the grafted or non-grafted rubber particles dissolved in styrene/ethylbenzene (Figure 4c). A similar behavior can be observed in systems containing dissolved polymers other than rubber [28][29][30]. Figure 5 displays the variation progress of grafting behavior under different TEMPO/DP275B ratio.…”

“…And the amount of asproduced PS phase is not up to that of rubber phase in a certain reaction interval, either. As a result, as shown in Figure 8d, the semi-continuous state or interpenetrating network of two-phase is formed [28], which is further unfavorable to impact resistance property.…”

Two‐phase Polymer Systems*

“…T h e grafted material is quite compatible with the surrounding glassy phase and is chemically bound to the rubber, resulting in excellent adhesion and improved impact strength. FIGURE 6 illustrates the im-:provement in impact strength that can be achieved by grafting over ordinary blending at equivaIent glass-rubber ratios. The effects of grafting versus blending have been discussed in detail?…”

“…ticIe.29 When light is normally incident upon a sample of thickness x, the transmittance, or ratio of transmitted intensity, I , to incident intensity, I , isgiven by where the turbidity, r , is defined by EQUATION 5. For spherical particles of radius r, the turbidity is = N~Y~K (6) where N is the nvmber of particles per unit volume and K is the scattering co: efficient.…”

Modeling of Phase Inversion and Particle Stability in the Dispersion Polymerization of Methyl Methacrylate in a Non‐polar Hydrocarbon Solvent

“…Both experimental detection and theoretical prediction of the phase inversion process are challenging problems. Although in some cases phase inversion can be detected by on‐line measurement of the system apparent viscosity or torque,25–28 this method is only applicable to polymerizations that undergo a significant viscosity change during phase inversion (i.e., viscosities of the coexisting phases are quite different). Moreover, on‐line microscopic observation of the reactive system is rarely available.…”