尼龙6/尼龙66比例对合金力学性能的影响

Effect of Nylon 6/66 Ratio on Mechanical Properties of Alloy

将尼龙6、尼龙66、增韧剂、抗氧剂1010作为原料,在同向双螺杆挤出机中,制备了增韧尼龙6/尼龙66复合材料,分析了不同尼龙6/尼龙66比例对增韧合金力学性能的影响。研究表明,随着尼龙66在尼龙6中比例不断提高,增韧尼龙6/尼龙66合金力学性能呈先增加后降低的趋势。当尼龙66在合金中的比例为25%时,复合材料拉伸强度、拉伸屈服强度、室温冲击强度、-40℃时冲击强度最高,分别为50.87 MPa、50.87 MPa.132.00 kJ/m^2和27.99 kJ/m^2;当尼龙66在合金中的比例为50%-75%时,复合材料断裂伸长率最高,为249.52%。尼龙66比例为25%的复合材料拉伸强度与冲击性能实现了较好的平衡,这是由于,在该比例下,增韧剂分散粒径约为0.5μm,而在其它比例下,分散相粒径在1μm以上。

Toughening nylon 6/nylon 66 alloy was extruded in co-rotating twin-screw extruder,using nylon 6,nylon 66,polyolefin impact strength modifier and antioxidant 1010. The effect of nylon 6/nylon 66 ratio on physical properties of nylon composite was evaluated. The results showed that adding nylon 66 into nylon 6,mechanical properties of composite increased firstly and then decreased. When the content of nylon 66 in nylon alloy was 25%,the tensile strength,yield strength,impact strength at room temperature and impact strength at-40 ℃ reached the peak level,were 50. 87 MPa,50. 87 MPa,132. 00 k J/m^2 and 27. 99 k J/m^2,respectively. When the content of nylon 66 in nylon alloy was between 50% ~ 75%,the elongation at break obtained the highest value,249. 52%. The nylon composite in which nylon 66 content was 25% had good balance of tensilestrength and fracture toughness,which could be attributed to smaller particle size of impact strength modifier. At the nylon 66 content of 25%,the particle size of impact strength modifier in nylon alloy was about 0. 25 μm,while the particle size in other alloy with different ratio of nylon 66 was larger than 1 μm.