Epoxy polymer, rarely crosslinked

The Solid-phase Extrusion of Rarely Crosslinked Epoxy Polymers... 

As was noted in the previous chapter, at present it is generally acknowledged [1] that macromolecular formations and polymer systems by virtue of the special features of their structure are always natural nanostructural systems. In connection with this fact the question of the use of this feature for improvement in the properties and operating characteristics of polymeric materials arises. It is obvious that for a structure, it is necessary to receive the relationships between the properties of the quantitative nanostructural model of the indicated materials. It is also obvious that if the dependence of a specific property on the structural state of a material will be unequivocal, then there will be quite sufficient modes to achieve this state. The cluster model of the amorphous state structure of polymers [2,3] is the most suitable for description of this state structure. It has been shown that basis of the structural element (cluster) of this model is a nanoparticle (nanocluster) [4], The cluster model was used successfully for the description of the structure and properties of crosslinked epoxy polymers [5]. Therefore the authors [6] carried out the study of the regulation modes of nanostructures and the influence of the latter on the properties of rarely crosslinked epoxy polymers. 

The rarely crosslinked epoxy polymer on the basis of resin UP5-181 has a low glass transition temperatnre T, which can be estimated according to shrinkage measurements data as being equal to 333 K. This means that the testing temperatures T = 293 K and Tg for it are close, which is confirmed by the small AOy valne for the native REP. This supposes (nanostructures) a small relative fraction of the nanoclusters [2, 3] and, since these nanoclusters have arbitrary orientation, an increase in results rapidly in their decay, which causes mechanical devitrification in the loosely packed matrix at > 0.36. The devitrificated loosely packed matrix gives an insignificant... 

Bisphenol F (BPF) is a mixture of three isomers 2,2 -, 2,4 -, and 4,4 -dihydroxydiphenylmethane, in the ratio 15%, 50% and 35%, respectively. It has also found application in the manufacture of epoxy resins, but as a fully crosslinked polymer it is rarely used in food-contact materials. Residues of... 

---