A Study On The Synthesis And Application Of Fatty Acid Salts

Stearic acid salt is an important component of metal soap,is an important fine chemical products. Octanoic acid salt mainly as a quantitative of polyvinyl chloride(PVC) heat stabilizers, drier and thickener. Stearic acid salt and octanoic acid salt are a part of the fatty acid salt,stearic acid salt mainly for aluminum stearate and magnesium stearate, octanoic acid salt mainly for aluminum 2-ethylhexanoate and magnesium isooctanoate in the paper. The process of stearic acid salt and octanoic acid salt and the effect of magnesium isooctanoate on the thermal stability of PVC were studied from the following aspects:(1) Finding preferable technical conditions for the synthesis of aluminum stearate of the fusion process by single factor experiments and orthogonal experiments. Under these conditions, the product yield was 85.6%, the aluminum content in the product was 4.97% and the melting point 145-155℃, which complied with the standard repuirements of chemical enterprises.FT-IR analysis showed that the synthesized IR spectra of product was consistent with the IR spectra of standard aluminum distearate; TG analysis showed that the products began to melt at about 150℃ and contained a small amount of aluminum hydroxide; XRD analysis showed that the products had a peculiarity of stratified crystalline structure,and contained a small amount of aluminum hydroxide.(2) Finding preferable technical conditions for the synthesis of magnesium stearate of the catalytic process by single factor experiments and orthogonal experiments. Under these conditions, the free acid in the product was 0.82%, the magnesium content in the product was 4.61%, and the melting point 116℃, which complied with the standard repuirements of chemical enterprises.FT-IR analysis showed that the synthesized IR spectra of product was consistent with the IR spectra of standard magnesium distearate; DSC analysis showed that the melting point of the products was between 90℃ to 130℃; XRD analysis showed that the products had a peculiarity of stratified crystalline structure,and the purity was high.(3) Finding preferable technical conditions for the synthesis of aluminum 2-ethylhexanoate of the direct process by single factor experiments. Under these conditions, the product yield was 46.5%, the aluminum content in the product was 8.5%.FT-IR analysis showed that the existence of aluminum 2-ethylhexanoate.(4) Finding preferable technical conditions for the synthesis of magnesium isooctanoate of the direct process by single factor experiments and orthogonal experiments. Under these conditions, the product yield was 92.5%,the magnesium content in the product was 4.0%.FT-IR analysis showed that the existence of magnesium isooctanoate.(5) The effects of the amount of magnesium isooctanoate and the thermal temperature on the thermal stability of PVC were studied by the Thermal aging oven method and Congo red method. The results showed that magnesium isooctanoate had good thermal stability of PVC.