Thermosetting prepolymers

Figure 3.9. Degree of planarkation of the thermoset prepolymer Coated from 50% solids solution Mw = 12,500.

Figure 3.8. Spin curves for the thermoset prepolymer at various molecular weights and percent solids.

Liquid crystalline thermoset system 1. Liquid crystalline thermoset prepolymer dihydroxy methylstilbene epoxy (Mn, 3600) 2. Curing agent 4,4 -methylene dianiline ... 

Synonyms Resorcinol-formaldehyde latex Resorcinol resin Classification Phenol-formaldehyde resin Definition Thermosetting prepolymer cured by reaction with paraformaldehyde... 

Therefore, processing of ICP and OM can only be performed using dispersions, whereby the matrix or medium in which the ICP would have to be dispersed, can be a polymer (thermoplastic or thermoset), prepolymer, water, or organic solvent, and the technology has been improved in the last years with the effect that practically all kinds of dispersions in all kinds of media are accessible [2j. 

Liquid state. This can be a polymer melt, low-MW thermosetting prepolymer, vinyl plastisol, or latex. 

Solidify. A thermoplastic melt can be cooled, a thermosetting prepolymer can be cured, a plastisol can be gelled, and a latex can be coagulated and/or evaporated. 

This latex is dispersed in a thermoset prepolymer capable of reacting both with the reactive shell and a curing agent. The fully reacted thermoset may have three or four distinct polymers, variously crosslinked and/or grafted to form a series of complex IPNs. Besides their practical importance, the spatial topology of the several compositions is unique. 

Example 5 of Reference 36 describes the preparation of two latexes, one reactive with the other. The graded rubber latex has a core of crosslinked poly(butyl acrylate) and a shell of linear poly(methyl methacrylate) containing hydroxypropylmethacrylate as the reactive species. The thermoset prepolymer emulsion is prepared from methyl methacrylate, containing glycidyl methacrylate as its reactive species. After polymerization, the two latexes are blended to yield a molding compound containing about 25% rubber, based on the core portions of the graded-... 

Injection Molding. Both thermosetting and thermoplastic polymers can be used in the injectionmolding process, though the practical requirements are very different for the two types of polymers. In injection molding, a cavity in the shape of the desired object is filled with molten thermoplastic or a thermosetting prepolymer resin. When the sohd polymer has formed, the object is removed from the mold and... 

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