Preparation and properties of laser direct structuring materials based on PA6/PPS

A series of laser direct structuring (LDS) materials including LDS-PA6, LDS-PPS, LDS-PA6/PPS, and long glass fiber (LGF) reinforced LDS material (LDS-PA6/PPS/LGF) were prepared based on polyamide 6 (PA6), polyphenylene sulfide (PPS) and their composites. The properties of the materials were characterized by TGA, thermal deformation tester, pendulum impact tester and material testing machine. The morphologies of regions after laser activation and layers after selective plating, and the reliability of plating layer were evaluated by optical microscope, SEM, crosscut tape and salt spray test. The results revealed that the thermal properties, water absorption resistance, flexural strength and modulus of LDS-PA6/PPS were between those of LDS-PPS and LDS-PA6. The introduction of LGF made the initial thermal decomposition temperature of LDS-PA6/PPS increased by 20 ℃. While the heat deflection temperature and flexural modulus of LDS-PA6/PPS/LGF were improved by 62% and 102% compared with those of LDS-PA6/PPS, respectively. It was found that increasing the laser energy and frequency, decreasing the scanning speed and hatch distance could enhance the superposition of laser pulse and effectively coarsen the surface of materials, which eventually contributed to the adhesion and deposition of copper particles during the subsequent selective plating process. The optimum laser activation process conditions were as follows: laser energy of 10 W, frequency of 70 kHz, scanning speed of 2500 mm/s and hatch distance of 25 µm. The copper coating of the LDS materials had uniform copper particles (particle size of approximately 40 µm), smooth surface and excellent electrical conductivity, the adhesion between the coating and the substrate was high, the resistance was less than 1.0 Ω. © 2022, Editorial Office of FINE CHEMICALS. All right reserved.