Beta-pinene (β-pinene) is a monoterpene, a natural compound found in plants. It is one of the two isomers of pinene, the other being α-pinene. It is a lackluster fluid solvent in liquor yet not in water. It has a woody-green, pine-like smell. Very recently, the cationic polymerization of β-pinene in toluene, using AlCl3 as the initiator, was shown to proceed smoothly and rather rapidly under MW irradiation. The radical random copolymerization of both α-and β-pinene with styrene under MW irradiation yields materials with Mn values considerably higher than those obtained under conventional conditions, but still with very low conversions.