Calcium carbonate is one of the most used inorganic fillers in the plastics industry. Nano calcium carbonate particles have the characteristics of small size, large specific surface area, and surface atoms in a highly activated state. Composite materials have the comprehensive advantages of inorganic, organic and nanomaterials and are widely used in plastic filling modification.
After research and testing, it was found that from the calcium carbonate content of 0% to the calcium carbonate content of 50%, the tensile properties of the blended plastics of calcium carbonate and PBAT first increased and then decreased. When the compatibilizer ADR is used, the tensile properties of the blended plastics of PBAT and calcium carbonate with a calcium carbonate content of 50% are significantly improved, and when the content of the coupling agent is 2% and the content of the solubilizer is 1%, the blending The tensile properties of plastics reach their peak.
It is also a composite material made by blending PBAT as the matrix material and the filler with a calcium carbonate content of 50%. The fully biodegradable composite material produced by the double-layer coating technology has good mechanical properties. Calcium carbonate was surface-modified by adding 0.5% KH560 and 0.5% titanate 102 using the double-layer coating method. The tensile strength of the prepared composite material has increased. Compared with the same additive, the surface modification of the calcium carbonate single-layer coating method is carried out, and the tensile strength of the prepared composite material is greatly improved.
The calcium carbonate masterbatch and PBAT were melt-blended through a twin-screw extruder to prepare a homogeneous material. The results showed that with the increase of calcium carbonate content, the elongation at break and tensile strength of PBAT showed a downward trend as a whole. When the content of calcium carbonate masterbatch was 40%, the elongation at break of PBAT decreased by 59.68%, and the tensile strength The impact strength decreased by 56.19%; the impact strength showed an upward trend with the increase of calcium carbonate content. When the calcium carbonate masterbatch content was 40%, the impact strength of PBAT increased by 46.52%; the increase of calcium carbonate content had no effect on the Vicat softening temperature of PBAT. The density of PBAT increases with the increase of calcium carbonate content. When the content of calcium carbonate masterbatch is 40%, the density is 1.44g/cm3, an increase of 19%.
Calcium carbonate was modified to obtain aluminate calcium carbonate (Al-CaCO3), and its effect on the degradation performance of PLA was investigated. The results show that Al-CaCO3 can greatly improve the degradation performance of PLA. Pure PLA degrades only about 20% within 8 days, but when the addition of Al-CaCO3 exceeds 30%, PLA can be completely degraded within 3 days, which is beneficial to the application of materials and home and industrial composting.
