Sulfur styrene melt, viscosity

Figure 9. Viscosity of a sulfur-styrene melt vs. reaction time and styrene content. Reaction temperature, 140°C.

Sulfur Concrete Modified with Styrene. If styrene is added to sulfur melts, the viscosity rises to a maximum within a few minutes irrespective of the styrene concentration (Figure 9). After reaching the maximum value, the viscosity decreases steadily to a constant final value which depends on the amount of styrene added. This characteristic behavior may be caused by thermal polymerization of the styrene followed by degradation of the polymer by reaction with sulfur. 

The use of styrene to modify sulfur melts and thus to improve the binder properties was unsuccessful. When producing sulfur binder modified with styrene, reaction times of at least 1.5 hr at 140°C were used, since by then the viscosity maximum had been passed and a constant viscosity value had been reached. Sulfur melts plasticized by... 

Molten sulfur was developed into a lightweight wallboard material because it can be foamed. Just above its melting point of 115°C sulfur viscosity decreases to a minimum at approximately 160°C. Above 160°C the viscosity increases rapidly (4). To foam the sulfur at the lower part of this temperature range, additives are required which prevent the foamed structure from collapsing. Additives such as phosphorus penta-sulfide and styrene monomer have been developed by Southwest Research... 

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