Research Of The Polyamide 6 On Enhancement And Flame Retardant Modification

Polyamide 6(commonly known as nylon 6, PA6) as a kind of engineering plastics, with good mechanical properties. With the rapid development of the domestic electronic, electrical, communications and consumer electronics industry,there is an increasing demand of PA6. Due to the presence of water absorption PA6 big disadvantage, its impact strength will be decreased. The scope of application of expanding and PA6, demands on the properties of PA6 flame retardant is getting higher and higher. On the basis of this requirement, the modified PA6 experiment is to adapt to the development of science and technology and market demand of inevitable direction.In this paper, short glass fiber to be modified PA6 by a twin-screw extrusion granulation synthetic SGF/PA6 composite materials, and test the mechanical properties were investigated short glass fiber content and extrusion process parameters on the mechanical properties of the composites. The results showed that short glass fiber content on the mechanical properties of the composites of remarkable.With the increase of short glass fiber content, the impact strength of the composites increased gradually, when the short glass fiber content of 42%, the impact strength reached its highest point 17.4k J/m2. Tensile strength and tensile modulus of composite materials, with the increase of short fiber content continues to increase, the rate of increase to slow the rapid growth from when short glass fiber content of 49%, the tensile strength of 149 MPa, compared pure PA6 doubling as much as tensile modulus reached 12043 MPa, is pure PA6 several times as much; while the yield tensile strain did not change significantly with the increase in the occurrence of short glass fiber content, has been in a steady trend, breaking elongation rate quickly drops to a certain extent into a slow decline; flexural strength and flexural modulus of the composites also increases short glass fiber content, the rapid growth of slow growth after the first,when the short glass fiber content of 49% when, the bending strength of 210 MPa.This paper also uses melamine cyanurate(MCA) on PA6 flame retardant modified by a twin-screw extrusion granulation synthetic MCA/PA6 composites, and test its combustion and mechanical properties. MCA addition of flame retardants,impact strength of the composite material to a certain degree of reduction of thetensile strength and bending strength has been enhanced to a certain extent. In the combustion performance, with increasing levels of MCA, composites LOI continuously improve, UL94 combustion performance has improved, but less of V-0.Since the composite material of the droplet phenomenon obviously, on this basis,were added melamine polyphosphate(MPP), magnesium hydroxide and antimony trioxide fire-retardant and other various synergistic flame retardant, improvement in the composite droplet phenomenon. MPP is added so that the composite limiting oxygen index was increased, when the MPP add reached 8%, LOI reached 31%,UL94 burning properties of V-0. Adding aluminum secondary phosphate(AHP) as the anti-dripping agent, composite droplet phenomenon to some extent, improved.AHP is added in such a composite limiting oxygen index increased slightly, when the MPP reaches 8%, LOI reached 29%, UL94 burning properties of only V-1 levels.Adding magnesium hydroxide to the MCA(15%)/MPP(4%)/PA6 composites, when magnesium hydroxide content reaches 10%, the LOI of the composite material of31.5%, vertical combustion level V-0, the mechanical properties decreased, but the amplitude is smaller.The paper determined formula of short glass fiber reinforced modified PA6 and the MCA/MPP/magnesium hydroxide flame retardant modified PA6. Contents of this issue has not been seen in the literature.