Continuous polymerization of lactam–lactone block copolymers in a twin‐screw extruder

Abstract

Continuous copolymerizations of ⑀-caprolactone with ⑀-caprolactam and -lauryl lactam were carried out in a modular intermeshing corotating twin-screw extruder. Sodium hydride (initiator) and N-acetyl caprolactam (coinitiator) were used to synthesize lactam-lactone copolymers in a twin-screw extruder. We consider the variables of feeding order and feed rate of comonomers on the reactive extrusion of lactam-lactone copolymers. It was observed that simultaneous feeding of both monomers with initiator and coinitiator in the first hopper produced a mixture of homopolymers. When we fed the lactam into the first hopper and caprolactone sequentially into the second hopper, we obtained the lactam-caprolactone block copolymers.However, when we fed caprolactone first into the first hopper and the lactam into the second hopper, the extruded product was a mixture of poly(⑀-caprolactone) and lactam monomer. We synthesized high molecular weight copolymers of poly(caprolactam-b-caprolactone) and poly(lauryl lactam-b-caprolactone) with different block lengths by sequential feeding of monomers. The block length of the block copolymer could be adjusted by controlling the feed rate of each monomer during reactive extrusion.

Synthesis and characterization of poly(ε‐caprolactones) and poly(δ‐valerolactone): Macroactivators for obtaining poly(esteramides)

“…The structures of the diisocyanate PCLOs and PVLO derivates were confirmed by the 1 spectra in CDCl 3 solution. The broad doublet at 3.6 ppm assigned to the OH protons from hydroxyl and carboxyl end-groups of PVLO or hydroxyl groups of the PCLO polyol disappeared after the functionalization, as mentioned above.…”

“…4a and b). The copolymerization reactions were also examined by 1 H NMR and FTIR analyses of the fractions extractable in chloroform, which established that only residual CLA monomer and oligomers were present. In the first stage of the polymerization, there was a depletion of the MA and then the copolymer becomes richer in A (PCLA) segments.…”

Recent Advances in Reactive Extrusion Processing of Biodegradable Polymer‐Based Compositions

“…As potential compatibilizing agents in polyamides/PCL blends, lactam‐CL block copolymers were prepared through reactive extrusion as well 66, 67. Continuous copolymerization of CL with ε‐ caprolactam (CLa) and ω ‐lauryl lactam (LLa) were carried out in a modular intermeshing co‐rotating twin‐screw extruder.…”

Poly[ethylene‐co‐(vinyl alcohol)]‐graft‐Poly(ε‐caprolactone) by Reactive Extrusion, 2 – Parameter Analysis

“…Therefore, in order to produce environmental friendly materials, poly( ε ‐caprolactone) (PCL), and various types of biodegradable plastics have been developed 19–21. Several researchers have successfully prepared PCL by ring‐opening polymerization by reactive extrusion 22–28. Only a few studies describing PCL‐containing copolymer synthesis by reactive extrusion have been reported 29–31.…”