Image courtesy of Paul Chaikin, NYU
A liquid mixture solidifies to different solid phases upon cooling (left) and heating (right). At low temperature, colloidal spherical particles form crystals due to pressure from collisions with the surrounding polymer. At high temperature, the polymer sticks to and bridges the particles, forming a random aggregate. At the crossing point (an intermediate temperature shown in the center), a liquid dispersion is formed because the attractive forces compensate for the collisions.