ISSN:
0021-9304
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Medicine
,
Technology
Notes:
Commercial bone cements usually contain hydroquinone as the polymerization inhibitor and N,N-dimethyl-p-toluidine as the accelerator in the benzoyl peroxide-initiated redox polymerization. The former compounds have certain shortcomings in their biocompatibility profile. Measurements of the setting times, polymerization exotherms, and postpolymerization strengths of the cured monomer-polymer compositions show that the hydroquinone can be replaced by food grade di-tert-butyl-p-cresol (BHT). The more reactive 4-N,N-(dimethylamino)phenethanol can replace 4-N,N-dimethyl-p-toluidine, yielding cements with shorter setting times and increased strengths. Excessive heat liberated on polymerization can be reduced by partial substitution of higher-molecular-weight methacrylates, e.g., dicyclopentenyloxyethyl methacrylate for methyl methacrylate, but there is a decrease in strength of the resulting polymer. More successful has been the addition to the monomer of 1% or 2% of the chain transfer agent pentaerythritol tetra(3-mercapto-propionate), which lowers the peak temperature without changing the physical properties of the cement. Compositions with short curing times, lower exotherms, and mechanical properties that exceed those of a commercial material have been formulated.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jbm.820200614
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