Process for manufacturing temperature-sensitive polymers utilizing a heat transfer fluid comprising a hydrocarbon fluid selected from aliphatic hydrocarbons, alicyclic hydrocarbons, aliphatic- or alicyclic-substituted aromatic hydrocarbons, or mixtures thereof, the hydrocarbon fluid having a boiling point from 220.degree. C. to 250.degree. C. and a melting point less than 40.degree. C., and temperature-sensitive polymer articles produced therefrom.