Carbon nanotubes were acidified with concentrated nitric acid, and a large amount of hydroxyl groups were grafted on the surface of carbon nanotubes by tetraethyl orthosilicate, and then the surface coated carbon nanotubes were formed by adding silane coupling agent KH550. Then, polylactic acid(PLA) was used as the main component, poly-β-hydroxybutyrate(PHB) was used as auxiliary material,and carbon nanotubes were used as reinforcement, the PLA/PHB/carbon nanotube composite material was prepared by using a Harker internal mixer. The composite materials were characterized by infrared absorption spectroscopy, scanning electron microscopy, micro-combustion calorimeter, capillary rheometer and Vicat softening temperature tester. The experimental results show that a large number of functional groups are grafted on the surface of the carbon nanotubes; After the addition of the elastomer PHB, the tensile strength,impact strength and elongation at break of the material increase, and the static bending strength decreases;After adding a small amount of carbon nanotubes, the tensile strength, impact strength and static bending strength of the composites are greatly improved, and the elongation at break is decreased; After the addition of PHB, the apparent viscosity of the bulk 7 is more affected by the shear rate; After the addition of carbon nanotubes, the apparent viscosity of the system increases and the thermal stability of the system enhances.
China Rubber/Plastics Technology & Equipment