8 августа, 2015 
Malyar Typical examples of physical, rheological, and mechanical characterization of sealants include specific gravity, percent solid, viscosity, flow, application time, working life, tack-free time, standard curing rate, liquid-immersed curing rate, resistance to rupture, low-temperature flexibility, peel strength, resistance to solvents, tensile strength, elongation modulus, chalking, accelerated storage stability, and hydrolytic stability. Usmani has proposed the use of parallel-plate rheometry (PPR) and dynamic mechanical analysis in the characterization and curing of polysulfide sealants [11-13].
Mechanical and physical quality control tests on polysulfide sealants can produce erroneous and misleading results, especially in predicting long-term performance. Problems such as poor adhesion, inadequate cure, and short working life can frequently occur, resulting in tedious and costly repair.
The composition of polysulfide sealants can be determined by centrifuging thinned polysulfide sealants and resolving them into components. Both quantitative and qualitative analysis can be performed [3,8]. The filler fraction can be analyzed by x-ray analysis and scanning electron microscopy (SEM). Nuclear magnetic resonance spectroscopy and gel permeation chromatography can be used for vehicle analysis. Mazurek and Silva have described a SEM method of analysis for cured polysulfide sealants [14]. Paul has studied the effects of environment on the performance of polysuifide sealants [15]. Numerous data can be obtained by monitoring the effects of various environmental conditions. Understanding chemical processes will assist in improving properties, however.
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