Abstract: Yttrium fumaropimaric acid (YFPA) was synthesized by using fumaropimaric acid and yttrium acetate tetrahydrate as raw materials. Structure and morphology of YFPA was characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction measurements, and effect of YFPA as a heat stabilizer on thermal stability of poly(vinyl chloride) (PVC) was investigated by Congo red and oven thermal aging methods. The results indicated that the YFPA product presented an amorphous and three-dimensional network structure connected by the coordinate bond of COO- and Y3+. The duration of thermal stability for PVC could be extended to 21 min when 1 phr of YFPA was added. The complex of YFPA with alcium stearate, zinc stearate and pentaerythrite could more effectively improve the long-term thermal stability of PVC and also retard its stainability at the initial heating stage. When the weight ratio of YFPA and calcium stearate was set to 1.5:1, the duration of thermal stability of PVC was improved up to 62 min. Meanwhile, no color change was observed from PVC specimen within 20 min, and no black color was found within 80 min.

Key words: yttrium fumaropimaric acid, poly(vinyl chloride), thermal stabilizer