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This study presents computational analysis of the complex dynamics observed in chemically blown polyurethane foams during reaction injection molding process. The mathematical formulation introduces an experimentally motivated non-divergence free setup for the continuity equations which reflects the self expanding behaviour observed in the physical system. The foam growth phenomena which is normally initiated by adequate pre-mixing of necessary reactant polymers, leading to an exothermic polymerization reaction, bubble nucleation, and gas formation, is captured numerically. We assume the dependence of material viscosity on the degree of cure/polymerization, gas volume fraction, and temperature as well as nondependence of mixture density on pressure. The set of unsteady nonlinear coupled partial differential equations describing the dynamics of the system are solved numerically for state variables using finite volume techniques such that the front of the flow is tracked w ith high resolution interface capturing schemes. Graphical representation of the foam volume fraction, evolution of foam heights, and temperature distributions is presented. Results from our simulations are validated with experimental data. These results show good quantitative agreement with observations from experiments

Sulphur-doped carbon was synthesized using a thiophene-based twin monomer. While tetra(thiophene-2-ylmethoxy)-silane can be converted into sulphur containing nanocomposites, which lead to microporous sulphur-doped carbon, it is possible to produce additional mesopores by the use of templates. Thus, a variety of sulphur-doped carbon materials with tailored pore texture are available.

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