Preparation, isolation and evaluation of novel N-acyloxytrialkylammonium salts as initiators for free radical polymerization of methacrylates under photochemical, thermal and accelerant promoted thermal conditions

POLY 132

Omari Ansong, ansong@temple.edu1, Susan Jansen, suebee@temple.edu1, Y. Wei2, Hui Lu, Huilu@dentsply.com3, S Li2, Y Guo2, and G Pomrink2. (1) Department of Chemistry, Temple University, 13th and Noris Streets, Philadelphia, PA 19122, (2) Department of Chemistry, Drexel University, Philadelphia, PA 19104, (3) Research and Development, Dentsply International, Milford, DE 19963
An efficient method for preparing and isolating new derivatives of N-acyloxytrialkylammonium salts as initiators for the free radical polymerization of methacrylates and dimethacrylates is reported. The new initiators were evaluated for the free radical polymerization of methyl methacrylate (MMA), tri-ethylene glycol dimethacrylate (TEGDMA) and ethoxylated bisphenol A dimethacrylate (EBPADMA) under photochemical conditions and at 60 oC both with and without sulfuric acid promotion. The resulting polymers were all characterized by TGA and in addition, PMMA was characterized by DSC and SEC. The new initiators are very effective in producing narrow MWD in PMMA and in effecting crosslinking in the dimethacrylates. The reaction time, polymer yield, molecular weight distribution (MWD), polydispersity index (PDI), decompostion temperatue (Td) and glass transition temperature (Tg), all improved under sulfuric acid promotion at 60 oC. Only a limited number of the salts could initiate the polymerization of TEGDMA under photochemical conditions.
 

General Papers: Functional Materials
6:00 PM-8:00 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, August 20, 2007 BCEC -- Exhibit Hall - B2, Sci-Mix

Division of Polymer Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007