zinc-based nontoxic heat stabilizer synergistic effect

Static tests showed that three zinc salt of PVC heat stabilizer effect has been quite effective in the Dioctyl phthalate  traditional lead salt, and better than the commercially available calcium zinc heat stabilizers. Congo red test paper method by the different proportions of zinc three salt as the sole heat stabilizer, and 4 parts by adding different heat stabilizer the thermal stability time, the results show that adding a single three salt 5.8 parts of zinc, the thermal stability time for the tin stabilizer  best. Through a static oven aging test comparison, zinc salts of PVC three initial and long-term stabilizing effect have good hue, the initial holding white effect is obvious, long-term discoloration than lead salt base, zinc burning phenomenon. With pentaerythritol vinegar or 3:1 proportion with diketone compound after the initial piece of PVC and long-term inhibition of discoloration effect is obvious.
Although organic zinc and other zinc compounds can effectively inhibit initial coloration of PVC, but because of its transformation products of zinc chloride de-HCl Reaction of PVC with a strong catalytic effect, so the ingredients in a very short time malignant degradation, resulting in the so-called "zinc burning" phenomenon. Therefore, the aluminium hydroxide  zinc-based heat stabilizers have and use a variety of synergistic stabilizers.
In the zinc-based heat stabilizer stabilizer synergist, rare earth salts of organic acids, β-diketones, β-amino-crotonate, dihydropyridine derivatives, nitrogen-containing compounds such as maleimide, hydrotalcite, zeolites, perchlorate, basic inorganic compound such as aluminum calcium phosphite is nearly 30 years the emergence of new species. Among them, rare earth salts of organic acids and synergistic stabilizer hydrotalcite progress in research is worth our attention.