In this study, polyamide 6 (PA6)/ nitrile butadiene rubber (NBR) based hybrid-nanocomposites reinforced with calcium carbonate and organo-clay as nanofillers in various content of 1, 3 and 5 phr were prepared and characterized. The nanocomposite samples were prepared through the melt processing method in an internal mixer. The effect of rubber phase (NBR) content (10, 30, and 50 wt. %), calcium carbonate content (1, 3, and 5 phr), and organo-clay content (1, 3, and 5) was investigated on morphology and mechanical properties of the nanocomposites. The mechanical properties were evaluated by tensile, flexural, and Charpy impact tests. The results showed that adding the NBR reduces the tensile strength, tensile modulus, flexural strength, and flexural modulus, and increases the impact strength. Introducing the nano-clay and calcium carbonate improves the tensile and flexural strength, tensile and flexural modulus, and decreases the impact strength. The nano-clay content from 1 to 3 phr improved the impact strength.

This work focuses on the preparation of copper nanoparticles-modified polyamide 6 composites (denoted as nano-Cu/PA6) by in situ polymerization, with which cupric oxide as metallic copper source is directly reduced to metallic copper in the process of the opening-ring polymerization of ε-caprolactam only using the reducing atmosphere of reaction system. The obtained composites are characterized by means of transmission electron microscopy, X-ray diffraction, laser granulometry instrument, and ultraviolet–visible absorption spectroscopy. Moreover, the friction and wear resistance, mechanical strength, and antistatic performance of as-prepared composites are also readily evaluated. The results show that cupric oxide as filler is reduced to metallic copper and the as-reduced copper nanoparticles with 4–5-nm-size clusters separately disperse in polyamide 6 (PA6) matrix. Additionally, the addition content (mass fraction) of cupric oxide has significant effect on the crystalline form of PA6, and γ crystalline form of PA6 is predominant when higher dosage of CuO is introduced to fabricating nano-Cu/PA6 composites. Moreover, introducing a proper amount of CuO filler favors to generate nano-Cu/PA6 composites with improved mechanical properties and wear resistance. Particularly, nano-Cu/PA6 composite prepared at a CuO content of 0.5 % possesses the best tensile strength and wear resistance, showing promising application as a functional polymer-matrix composite.

In this work, melamine cyanurate (MCA) and boehmite (BM) were used to improve the flame retardancy of polyamide 6 (PA6), and a series of BM/MCA/PA6 composites were prepared. The effects of MCA and BM on flame retardancy, combustion and thermal degradation behavior of 15-MCA/PA6 and BM/MCA/PA6 composites were investigated by methods of limited oxygen index (LOI) measurement, vertical burning test, cone calorimeter test and thermogravimetric analysis (TGA). The results showed that MCA can effectively flame retardant PA6. When 15 wt% MCA was added to PA6, composite sample (15-MCA/PA6) possessed LOI value of 30. 4% and V0 rating (3. 2 mm) in UL-94 test. By replacing part of MCA with BM, with an increase of BM amount, the flame retardancy of BM/MCA/PA6 composite was better at first, but then got worse, and mechanical properties were increased. The flame retardancy, thermal stability and combustion behavior data of 4-BM/11-MCA/PA6 composite were better than 15-MCA/PA6 composite, indicated that appropriate amounts of MCA and BM in PA6 had synergistic flame-retardant effects. The time to ignition (TTI), the peak of heat release rate (PHRR), total heat rate (THR), total smoke release /total mass loss (TSR/TML) and fire performance index (FPI) of 4-BM/11-MCA/PA6 composite were 53 s, 322. 5 KW. m−, 2, 79. 8 MJ. m−, 2, 98. 3 g−, 1 and 0. 16 s. m2. kw−, 1, respectively. The LOI value of 4-BM/11-MCA/PA6 composite was 33. 8% with V0 rating (2. 0 mm) in UL-94 test.