Study On Properties Of Pigment Dipersion In Nylon 6

The diameter of superfine nylon6 fiber is about 1 to 3 nm that the coloring masterbatch for it compose with nano-dispersed pigments. The way dispersing pigments by organic solvent and hyperdispersants is prepared for PA6/pigment masterbatch that is for coloring PA6 by HAAKE torque rheometer. The colored nylon6 has good pingments dispersion. By testing surface Zeta potential of pigment particle, we can study the stability of pre-dispersion; By blending different masterbatch and PA6, we can investigate the processing properties of PA6/pigment composites; By scanning electronic microscope of dispersion, we can know real situation of dispersed pigments.The results showed that DMF was so better solvent for pigments because it had good wetting property for carbon black, phthalocyanine blue and sicopal yellow. When choosed polyurethane for carbon black and sicopal yellow and low molecular weight of poly amide for phthalocyanine blue, the Zeta potential of carbon black,phthalocyanine blue and sicopal yellow that changed-24.5mV to-28.5mV,-9.1mV to-17.6mV and-5.3mV to-15.2mV told us that they had good stability pre-dispersion in organic solvent. Their average particle size were 57nm,117nm,104nm respectively. The results of PA6/pigment composites showed tensile strength and elongation at break of PA6/CB, PA6/phthalocyanine blue and PA6/sicopal yellow composites improved first and then decreased with the addition of three kinds of masterbatch. The PA6/CB composite containing 15% PA6/carbon black masterbatch had tensile strength of 83.70MPa, elongation at break of 38.10%, which compared with pure PA6, mechanical properties increased by 30.39%,25.58%; the data of PA6/phthalocyanine containing 10% masterbatch were 128.0MPa and 50.36%, increased by 99.41%,65.99%; the data of PA6/sicopal yellow containing 5% masterbatch were 67.49MPa and 32.07%, increased by 5.14%,5.70%.By testing dynamic mechanical properties Of the PA6/pigment composites, the results showed that temperature of glass transition (Tg) of the three composites were 43.85℃,43.04℃and 44.89℃that have decreased slightly compared with pure PA6 by 6.48%,8.56%,4.63% respectively. Thermal performance is nearly unchanged.