Polyamides from lactams by centrifugal molding via anionic ring-opening polymerization

Reactive microencapsulation of carbon allotropes in polyamide shell-core structures and their transformation in hybrid composites with tailored electrical properties

“…The Mark-Houwink equation for PA6 was used with K = 5.066·10 -4 and ! = 0.74 [38]. Flow times are recorded as an average of Table 1.…”

Dispersion of nano-silica in monomer casting nylon6 and its effect on the structure and properties of composites

“…Considering that the tremendous energy offered by ultrasonic is likely to break the nanoparticles aggregations into smaller ones or even mono-dispersing particles [13], in the present work, ultrasound was employed to disperse nanosilica in melted caprolactam. Therefore, the agglomerated nanoparticles would be pulled apart and coated with caprolactam, leading to the improved stability of smaller aggregations and mono-dispersing nanoparticles against re-agglomeration, and (iii) in comparison with classical hydrolytic polymerization of caprolactam which takes about 12-24 hrs [14,15], the rapid anionic polymerization of caprolactam (usually within 1 hr [12,16]) also contributed to the avoidance of re-agglomeration and deposition of nanoparticles during the polymerization process, leading to the uniform distribution of nanoparticles in polymer matrix (Figure 1). Besides, it is well known that the anionic polymerization of caprolactam proceeds well below the melting temperature of the nylon6, which could avoid the degradation in comparison with conventional melt compounding.…”

Polyamide from lactams by reactive rotational molding via anionic ring-opening polymerization: Optimization of processing parameters

“…It is well known that anionic polymerization of !-CL (APCL) occurs faster (i.e., over a few minutes) than classical hydrolytic polymerization, which takes about 12-24 h [4]. A fast polymerization process in addition to good mechanical properties of PA6 results in a wide range of applications for this polymer in reaction injection molding [5,6], rotational molding [1,7] and centrifugal molding [8][9]. This makes PA6 one of the main engineering materials in use today.…”