TY - JOUR T1 - Quantitative and Mechanistic Measurements of Container/Closure Integrity: Viscoelastic Measurements of Eiastomeric Closures JF - PDA Journal of Pharmaceutical Science and Technology JO - PDA J Pharm Sci Technol SP - 127 LP - 141 VL - 42 IS - 4 AU - Dana K. Morton AU - Nicholas G. LOrdi Y1 - 1988/07/01 UR - http://journal.pda.org/content/42/4/127.abstract N2 - A method of characterizing the viscoelasticity of elastomeric closures is demonstrated using a DuPont 983 Dynamic Mechanical Analyzer (DMA). Using the fixed frequency mode of operation, molded closures are defined in terms of their viscous [G″(ɷ)] and elastic [G′(ɷ)] moduli. Moduli are shown to be a function of closure formulation, and are indicative of the presence of inert polymer coatings. Exploratory closure analysis on the rheological impact of heat is presented. Evaluation of closures by the DMA is compared to the more traditional approach of stress relaxation and creep tests using conventional equipment. ER -