Monomer casting

Nylon-6 can also be produced from molten caprolactam using strong bases as catalysts (anionic polymerization) this is used as the basis of monomer casting and reaction injection mol ding (RIM). Anionic polymerization proceeds much faster than the hydrolytic route but products retain catalysts which may need to be extracted. 

Once RIM had been developed for polyurethane molding, the industry began asking whether it could be applied to other fast polymerization/cure reactions. It was quite readily applied to nylon 6 monomer casting, but the cost of the caprolactam monomer appeared non-competitive. It was also suggested for epoxy cure and possibly other fast reactions, but none of these have yet been developed commercially. 

Monomer casting is effective for the fabrication of shaped products in practically all sizes and thicknesses. It also provides economic advantages in low or high volume manufacture. Cast parts can be either produced to size or they can be cast and then machined to strict tolerances as required in accordance with end-use needs. Monomers of the lactam family are used to make cast nylon. They will polymerize under various conditions. 

Igopas. [Igr last-Faigle AG] Monomer casted polyamide. 

Monomer casting, followed by controlled (co)polymerization (e.g., PMMA, epoxies)... 

Nylon-6 by monomer casting Glass fiber reinforced nylon-6,6 1962 Poly(w-phenylene isophthalamide)... 

Low capital investment, very fast cycle, and low energy requirements combine to make this process very economical. In addition to polyurethanes, the process has been used for nylon 6 monomer casting and has been suggested for epoxy and other thermosetting resins. 

Finally, Yan et cd. [66] utilized the in-situ anionic ring-opening polymerization to prepare monomer casting PA 6-MWNTs nanocomposites. The typical functionalization process of MWNTs by COOH groups was not therein applied, as the... 

D5989 Extruded and Monomer Cast Shapes from Nylon ... 

The technology of "monomer casting" which is used to polymerize large parts at normal pressure directly in the mold was introduced about 1960 [26, 34]. The process is applied to manufacture heavy rods, tubes and plates which are subsequently machined into finished items. Furthermore, large containers such as fuel tanks are produced by rotational molding. 

A. D. Liu, T. X. Xie, and G. S. Yang, Synthesis of exfoliated monomer casting polyamide 6/Na-l—montmorillonite nanocomposites by anionic ring opening polymerization. Macromolecular Chemistry and Physics, 207 (2006), 701-7. 

As already mentioned in Section 4.14.13.1, the activated anionic polymerization of CL has undergone interesting industrial developments in the field of well-established monomer casting process, as well as in the more recent areas of RIM (RIM and R-RIM), resin transfer molding (RTM), and rotational molding. In addition, reactive extrusion processes, already erqrlored since 1968, are now gaining renewed attention for the easy preparation of nanocomposites and nanoblends, as described in the following. 

Monomer casting, already described in some German and US patents prior to WWII, has been fuUy developed only since 1956,... 

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