Modification of nylon-6 with poly (m-phenylene isophthalamide) via MDI as a chain extender

Reinforcement of flexible nylon-6 by using poly (m-phenylene isophthalamide) PmIA (Nomex) using (MDI) 4,4-diphenylene methane diisocyanate as a chain extender was studied. Observation by scanning electron microscopy showed that the multiblock copolymer had a homogeneous texture. From the differential scanning calorimetry measurements, the multiblock copolymers were shown to have only one melting point, T _m, which is higher than that of nylon-6. The wide-angle X-ray diffraction pattern shows that nylon-6 has two diffraction peaks at 2=20° and 23.8°. However, the multiblock copolymer has only one peak at 2=20°, indicating a different crystal structure of multiblock copolymers. The copolymers appear to have a significant reinforcing effect on the mechanical properties.