Application of Zinc Oxide to Obtain and Modify Properties of Adipate Plasticizer of Polyvinyl Chloride

Abstract

Heterogeneous catalysts are widely used in basic research and in the petrochemical industry due to their effectiveness. In modern times, interest in this type of catalyst and, in particular, in mineral oxides is associated with the technological design of the process, namely: The absence of waste emissions, and the possibility of regeneration and reuse of the catalyst, which meets the criteria of green chemistry. For this reason, the preparation of non-toxic adipate plasticizers is expediently carried out under conditions of heterogeneous catalysis. Zinc oxide was chosen for this purpose, and as initial reagents: Adipic acid, butoxyethanol, and phenoxyethanol. For synthesized butoxyethylphenoxyethyl adipate by thermogravimetry on a TGA-DSC-combined thermal analysis instrument and differential scanning calorimetry on a DSC-1 instrument («Mettler Toledo»), the following properties were studied: Thermal stability, melting and crystallization temperatures, polymer compatibility. An analysis of the data in comparison with di-2-ethylhexylphthalate confirmed the possibility of using it as a plasticizing additive in PVC compositions. The zinc compound obtained in situ as part of the developed plasticizing composition contributes to increasing the color and thermal stability of the obtained PVC compositions.

Designing of Green Plasticizers and Assessment of the Effectiveness of Their Use

“…The oxyethylation reaction of alcohols has been well studied [ 38 , 39 , 40 ]. The ethoxylation of alcohols and the characteristics of the products are described in our previous works [ 25 , 30 ].…”

“…Ethoxylated alcohols were prepared as described previously [ 30 ]. Briefly, the calculated amount of alcohol and sodium hydroxide catalyst in the flask is heated to 110–120 °C and then purged with nitrogen to remove air; then, prepared ethylene oxide is gradually introduced.…”

“…Unsymmetrical adipates were obtained according to the method described earlier [30]. Briefly, 150 mL of o-xylene, 1 mol of ethoxylated alcohol, 3.0 g (1% by weight) of ptoluenesulfonic acid, and 146 g (1 mol) of adipic acid were charged into the reaction flask, and the temperature was slowly raised to 90-100 • C. Stirring was continued for 1.5 h. The end of the reaction was determined by the acid number of the esterificate.…”

“…The use of natural biodegradable plasticizers with low toxicity and good compatibility with traditional polymers is a growing trend in the development of bioplastics. Epoxidized triglyceride vegetable oils from soybean oil, linseed oil, castor oil, sunflower oil, and fatty acid esters are widely used as natural-based plasticizers [ 29 , 30 , 31 , 32 ]. However, in some applications, a complete substitution with natural-based plasticizers is simply not possible, which is why a wide range of commercially available biodegradable synthetic plasticizers have been developed over the past decades: esters of adipic, azelaic, sebacic, citric, and tartaric acids [ 33 ].…”

An Overview of the Main Trends in the Creation of Biodegradable Polymer Materials

“…e use of such alcohols helps to increase the degree of decomposition of the material, since ether bonds are easily hydrolyzed. We are also investigating the possibility of using the developed adipates in PVC compositions, studying the effect of the obtained plasticizers on the biodegradation of plastics, as well as the ecotoxicity of their decay products [100][101][102][103].…”