This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Jones, D.W. Articles by Robertson, K.N. Search for Related Content PubMed PubMed Citation Articles by Jones, D.W. Articles by Robertson, K.N. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Medline Plus Health Information Dentures Social Bookmarking                         What's this?

Chemical and Molecular Weight Analyses of Prosthodontic Soft Polymers

Division of Dental Biomaterials Science, Department of Applied Oral Science, Faculty of Dentistry, Dalhousie University, Halifax, Nova Scotia, Canada B3H 3J5

G.C. Hall

Division of Dental Biomaterials Science, Department of Applied Oral Science, Faculty of Dentistry, Dalhousie University, Halifax, Nova Scotia, Canada B3H 3J5

E.J. Sutow

Division of Dental Biomaterials Science, Department of Applied Oral Science, Faculty of Dentistry, Dalhousie University, Halifax, Nova Scotia, Canada B3H 3J5

M.F. Langman

Division of Dental Biomaterials Science, Department of Applied Oral Science, Faculty of Dentistry, Dalhousie University, Halifax, Nova Scotia, Canada B3H 3J5

K.N. Robertson

Division of Dental Biomaterials Science, Department of Applied Oral Science, Faculty of Dentistry, Dalhousie University, Halifax, Nova Scotia, Canada B3H 3J5

A number of studies have been made investigating the properties of dental prosthodontic soft polymer materials. In such materials, which are used as short-term denture soft liners, the polymer component is complexed with one or more plasticizers. This lowers the glass transition temperature, Tg, of the polymer by allowing greater chain mobility and produces a more flexible material. Little information is available relating to the polymer components of such soft-lining materials. The chemical composition and molecular-weight distribution of a polymer help to determine its ability to form a plasticized soft polymer-gel. In the present work, both pyrolysis depolymerization/gas chromatography (GC) and size exclusion chromatography (SEC) have been used to characterize 11 commercial polymer powders. By use of SEC and polymer standards having a narrow molecular-weight range, it has been possible for accurate molecular-weight distributions to be determined for all 11 powders. The peak molecular weights were found to be between 1.79 x 10⁵ and 3.28 x 105. These values are above the molecular weight at which chain entanglement occurs. The polydispersity ratios (Mw/Mn) were between 2.09 and 4.48. Methacrylate polymers can be readily decomposed thermally to their constituent monomers, which, once recovered, can be analyzed by gas chromatography. The simple pyrolysis apparatus used in the present study was easily assembled and was capable of producing both qualitative and quantitative results. None of the commercial polymers analyzed gave methacrylate decomposition products with pendant chains greater than ethyl (-CH₂-CH₃). All of the commercial polymers successfully studied by the pyrolysis test method proved to be poly(ethyl [100-79%]/methyl [0-21%] methacrylate) polymers or co-polymers.

Journal of Dental Research, Vol. 70, No. 5, 874-879 (1991)
DOI: 10.1177/00220345910700050201


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				B.S. Graham, D.W. Jones, and E.J. Sutow An in vivo and in vitro Study of the Loss of Plasticizer from Soft Polymer-gel Materials Journal of Dental Research, May 1, 1991; 70(5): 870 - 873. [Abstract] [PDF]