Preparation of PS‐g‐PA6 copolymers by anionic polymerization of ε‐caprolactam using PS precursors with N‐carbamated caprolactam pendants as macroactivators

Abstract

ABSTRACT:The graft copolymer of polystyrene and polyamide 6 (PS-g-PA6) was investigated by anionic polymerization of e-caprolactam (CL), using the free radical copolymer of styrene and a kind of allyl monomer containing N-carbamated caprolactam group as macroactivator (PS-CCL). CL monomers were grafted onto PS-CCL backbone via initiating N-carbamated caprolactam (CCL) pendants along its backbone to form the graft copolymer in the presence of catalyst sodium caprolactamate. The macroactivator was characterized by Fourier-transform infrared spectroscopy and nuclear magnetic resonance, and the graft copolymer by the selective solvent extraction technique using methanol and chloroform as solvents. PS-g-PA6 copolymers with different PS content were synthesized to study the effect of PS on morphology, crystallinity, dimensional stability, and thermal properties, using scanning electron microscopy, X-ray diffraction, water absorption measurement, thermogravimetric analysis, and differential scanning calorimetry. The results show the percentage crystallinity of graft copolymer decreases with increasing PS content, but the addition of PS scarcely influences the crystalline structure of PA6. The graft copolymer has improved thermal properties and dimensional stability.

The reactive compatibilization effect of copolymer macroactivator for immiscible anionic polyamide 6/polystyrene blends via in situ polymerization

“…It can be seen that there are two weight loss regions when the IEM has not been added. The first one between 290 and 360 °C is due to the degradation of low‐molecular weight polyamides and oligomers, and the second one which was located between 360 and 500 °C is due to the degradation of APA6 chain into low‐molecular weight substances . Yet for APA6/PS blends, when the IEM was added, the first weight loss region disappeared which indicates the degradation of APA6 at low temperature is hindered.…”

“…Liu et al . used the free radical copolymer of St and a kind of allyl monomer containing N‐carbamated caprolactam group as macroactivator (PS‐CCL) to generate the graft copolymer of PS‐ g ‐APA6 …”

Polymers and Related Composites via Anionic Ring-Opening Polymerization of Lactams: Recent Developments and Future Trends

“…The basic difference compared to that of Hu [ 76 , 77 ] was that PS itself was a copolymer containing styrene and an isocyanate group bearing styrene derivative. The strategy was similar to the above one in the work of Liu [ 79 ] who synthesized a copolymer composed of styrene and an allyl monomer having a carbamated caprolactam moiety. PA-6 chains were grafted on this styrenic macroactivator via anionic polymerization of CL at T = 170 °C.…”