Porapak:

Porapak is a porous polymer composed of ethylvinylbenzene cross-linked along with divinylbenzene to form a uniform structure of a discrete pore size. Its column holds only the porous polymer beads screened to a definite mesh range and no liquid phase or solid support is used. A porous polymer beads serve the function of both the liquid phase and the solid support. Apparently, a solute molecule positions straight from the gas phase within the amorphous polymer. There are six Porapak materials available like kind P,Q,R,S,T, and N. Type P and Q are non-polar phases type, and  R,S,T and N are moderately beads. Porapak N has been established for separation of formaldehyde mixtures and for the separation of acetophenone and ethylene. All beads are available in several particle sizes ranging from 50/80 mesh to 150/200 mesh. All the polymers are stable to 250°C except Porapak T that is stable upto 200ºC.

Porapak is used primarily for efficient separations of a huge variety of associative low molecular weight solutes. Porapak columns shall be conditioned prior to use to erase residual solvents from the polymerization procedure. The utility of the material is extremely well demonstrated through a variety of separations display in Figure. The conditions are mentioned.

Figure:  Applications of porapak column