(thiol Isooctyl) Synthesis And Thermal Stability Of The Antimony

In this thesis, a review has been made systematically in the field of heat stabilizer for PVC at home and abroad, especially in the current situation and the applied prospect of the research on antimony serial heat stabilizers. We have proposed a novel type of antimony mercaptides, e.g. antimony pent(iso-octyl thioglycollate) for PVC which possess excellent thermal stability at lower usage lever.Following the synthesis principle of the normal antimony mercaptides and choosing a suitable procedure, we have synthesized antimony pent(iso-octyl thioglycollate), Sb(SCH2COOCgHn)5 , from industrial sodium antimonate.isooctyl thioglyclate and hydrochloric acid . The reaction conditions have been optimized through tests. The experimental results show: sodium antimonate is reacted with isooctyl thioglyclate at the mole ratio nNa2Sb2O6:n10HSCH2cooc8Hi7=l-2:l , hydrochloric acid is added dropwise at the mole ratio nHci:n5HSCH2cooc8H17=l.2:l, with toluene as azeotropic solvent for about 3.5 hours to form the product antimony pent(iso-ocryl thioglycollate), the yield of the product is 92.8%.The resultant product is filtered to remove unreacted sodium antimonite and additional byproduct of reaction,sodium chloride.The product is then vacuum distilled at 70癈/2kPa to remove the solvent;then it is heated to collect the distilled component antimony pent(iso-octyl thioglycollate) at 127癈/2kPa, The antimony content is 10.3%, and the stretching vibration of S-H at 2560 cm"1 disappears in IR. The merits of the synthesis are low price of the reactant feeds, simplicity of the synthetic process and height of catalytic efficiency.The thermal stabilities of antimony pent(iso-octyl thioglycollate) are tested through cango red test paper , aging oven and thermogravimetry. The experimental results show: the product possesses excellent thermal stability for PVC resin at lower usage lever, it can obtain good thermal stability while added 2.5phr(per hundred resin) of antimony pent(iso-octyl thioglycollate) in PVC. Furthermore, the synergistic effects of the products with calcium stearate, barium stearate, barium bis (iso-octyl thioglycollate), barium bis thioglycollate,rare eath stearate,rare earth bis dodecanoicoxy have been studied to enhance its thermal stability. It shows calcium stearate, barium stearate, barium bis(iso-octyl thioglycollate), barium bis thioglycollate,rare eath stearate,rare earth bis dodecanoicoxy have positive synergistic effects, the best is barium bis(iso-octyl thioglycollate) .In the end, the heat stability mechanism of antimony serial heat stabilizers forPVC has been presumed.