Performance Study Of Liquid Multivariate Complex Thermal Stabilizer

Since the excellent featureas: environmental-benign, easier to quantify, low in price, dustless during production and use, liquid complex metal soap thermal stabilizer is becoming more and more popular, especially as thermal stabilizer in flexible transparent Poly vinyl chloride (PVC) produts, such as, transparent wire, flexible toy, medical appliance, food packaging film, artificial leather, etc.This paper mainly studied the production technology of mix organic acid liquid Ca/Zn thermal stabilizer. The synthesis technology of the intermediate metal soap was mainly investigated, and the specific effect of metal soap, the co-stabilizer as well as antioxidants on the thermal stability of PVC was also investigated. Very good compatibility among all of the components was found by appropriate alotm, and special formulations adequate for different processing condition were designed, some special regularity between the thermal stability of PVC and synthesis technology was also found, based on this, plant-scale production of 250 t/a was carried out.By adulterating La³⁺ into liquid Ba/Zn, La/Ba/Zn triple system was developed, and the new thermal system was applied to flexible PVC, the synergistic efffect among La/Ba/Zn was investigated by discoloration method, TG and UV; The effect of La³⁺ on the processability of PVC was also studied with the help of torque rheometer. The mechanism of La³⁺ modifying liquid Ba/Zn was probed on the principle of electronic configuration.The experiment result indicated that the thermal stability of liquid Ca / Zn can be significantly improved through rational assortment. When the complex complex system contained Zn: 1.5%, Ca: 2%, triphenyl phosphite(TNPP): 10%, antioxidant 1010: 1%, antioxidant 1076: 1%, antioxidant 168: 2%, the PVC films contained 3phr such stabilizer can keep stability in 180℃oven for 70min(time of discoloration).Research showed that La³⁺ has very strong ability to inhibit zinc burn of PVC, it can be used in high-zinc formulations, so as to improve short-term and long-term thermal stability; when liquid thermal stability contains Zn 3%, La³⁺ 5%, the discoloration time at 180℃can be to prolonged to 40min; There were remarkable synergism among La/Ba/Zn system, when La/Ba has the mass ratio of 1:1, the synergism reached the highest level, and the zinc-burn time at 180℃come up to 60min; besides, La³⁺could also improve the processing performance of PVC resin, compared to Ba/Zn and Ca/Zn, La/Ba/Zn triple system could make the PVC resin easier to be processed.