Curing oligomers

Soviet scientists have developed a cold-cure EDS material87). Note that the epoxy binders used are in fact generally hot-cure oligomers (from the point of view of the functional groups used and the completion of cure). It turned out that the forced elastic limit and the compression elastic modulus of the matrix are the same for both hot and cold cures. The good mechanical properties of a cold cured syntactic foam seem to be due to strong intermolecular bonds. 

Figure 16 represents schematically a vatiation of molecular mass and content of sol fraction, calculated on the basis of the branching the ory, in the process of three-dimensional polycondensation of multifunctional compounds [89, W]. According to these calculations, the weight-average molecular mass of curing oligomer increases monotonically up to the gel point where it diverges. At this same point the gel appears. A real variation of the same characteristics, obtained on the basis of GPC analysis of curing of an epoxy resing with diamine and dibutylphthalate has a different nature (Fig. 17). Molecular mass of the resulting...

The composition of urethane acrylates can be varied In order to achieve certain end properties required by the Intended application. The structure-property relationships discussed In this paper can provide guidance In the intelligent design of this class of radiation cure oligomer. 

Features Fast cure oligomer tough, high gloss good flexibility chem. and abrasion resist. 

The analysis of possible correlations between thermodynamic and kinetic patterns of structure formation in initial and cured oligomer system is presently not sufficient. This complex problem has taken attention of seientists not so long time ago[122,197-200]. Let s take just one of its aspects to consider. 

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