  We study a two-component model for gelation consisting of $f$-functional
monomers (the gel) and inert particles (the solvent). After equilibration as a
simple liquid, the gel particles are gradually crosslinked to each other until
the desired number of crosslinks has been attained. At a critical crosslink
density the largest gel cluster percolates and an amorphous solid forms. This
percolation process is different from ordinary lattice or continuum percolation
of a single species in the sense that the critical exponents are new. As the
crosslink density $p$ approaches its critical value $p_c$, the shear viscosity
diverges: $\eta(p)\sim (p_c-p)^{-s}$ with $s$ a nonuniversal
concentration-dependent exponent.
