氧化石墨烯/苯甲酸钠复合成核剂协同改性PA6纳米复合材料的性能

Properties of Nylon PA6-based Nanocomposites Co-modified with Graphene Oxide/sodium Benzoate Complex Nucleating Agent

先用水热法合成氧化石墨烯(GO)/苯甲酸钠(Sb)复合成核剂(GO-Sb),然后用熔融共混法制备尼龙6(PA6)/GO-Sb纳米复合材料,研究了分别添加GO和Sb、同时添加GO-Sb对PA6纳米复合材料的形态、力学和热性能的影响。结果表明:GO与Sb之间存在静电相互作用和π-π共轭,Sb的加入能促进PA6中γ晶的形成。GOSb作为异相成核剂均匀分散在PA6中,使PA6纳米复合材料的结晶温度、结晶度和热变形温度提高。PA6-GOSb(100/0.05/0.25)纳米复合材料的拉伸强度和冲击强度分别比纯PA6提高了69.9%和157.1%。PA6-GO-Sb(100/0.05/0.25)纳米复合材料的拉伸强度、冲击强度和弹性模量分别比PA6-GO-Sb(100/0.3/0)纳米复合材料提高了13.6%、186.4%和52.6%。与纯PA6(k=0.238 W/m·k)相比,PA6-GO-Sb(100/0.3/0)纳米复合材料(k=0.536 W/m·k)的热导率提高了125.2%,PA6-GO-Sb(100/0.05/0.25)纳米复合材料(k=0.854 W/m·k)的热导率提高了258.8%。

Firstly,a complex nucleating agent(GO-SB)was synthesized by hydrothermal method with graphene oxide(GO)and sodium benzoate(SB)as raw material,and then nanocomposites of nylon6(PA6)/GO-SB were prepared by melt blending method with PA6 as matrix and GO-SB as complex nucleating agent.The effect of the introducing GO and SB separately,and GO-SB simultaneously on the morphology,mechanical and thermal-property of PA6 based nanocomposites were investigated.The results show that there are electrostatic interaction andπ-πconjugation between GO and SB,and the addition of SB can promote the formation ofγ-crystals in PA6.GO-SB was uniformly dispersed in PA6 matrix as heterogeneous nucleating agent,which could induce the increase of crystallization temperature,crystallinity,and thermal deformation temperature of PA6 based nanocomposites.The tensile strength and impact strength of PA6/GO-SB(100/0.05/0.25 in mass fraction)nanocomposites are 69.9%,and 157.1%higher than those of pure PA6,respectively.The tensile strength,impact strength and elastic modulus of PA6/GO-SB(100/0.05/0.25)nanocomposites were increased by 13.6%,186.4%and 52.6%,respectively,compared with those of PA6/GO-SB(100/0.3/0)nanocomposites.Compared with k=0.238 W/m·k of the pure PA6,the thermal conductivity k=0.536 W/m·k of PA6/GO-SB(100/0.3/0)nanocomposite is increased by 125.2%;while the thermal conductivity k=0.854 W/m·k of PA6/GO-SB(100/0.05/0.25)nanocomposites is increased by 258.8%.