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Using maleic anhydride and 6-amino-1,3-dimethyluracil as raw materials, by adding zinc oxide and introducing metal ions, the aminouracil zinc maleate (AM-Zn) was synthesized. The structure of the product was analyzed by Fourier transform infrared spectroscopy and 1 H NMR spectroscopy. The molecule contains ester group, carbon-carbon double bond, carboxylate and diazo group, which can be used as the main thermal stabilizer for poly(vinyl chloride) (PVC). The thermal stability and excellent resistance to zinc burning of AM-Zn were characterized by Congo red method, thermal aging method, thermal weight loss method, electrical conductivity, and other detection methods. In addition, the compound use of AM-Zn and CaSt 2 could further improve the thermal stability performance, which was excellent compared with the commercially available CaSt 2 /ZnSt 2 . The thermal stabilization effect was the best when CaSt 2 /AM-Zn = 2:1, the initial whiteness could reach 50 min, and it was not completely blackened and aged within 80 min. The static stabilization time was 65 min, and the thermal stabilization time is increased by 40 min compared with CaSt 2 /ZnSt 2 . The thermal stabilization mechanism was analyzed, and the designed and synthesized AM-Zn, a multifunctional molecular structure, had a strong potential as a thermal stabilizer for PVC.aminouracil maleamic acid zinc, anti-zinc burning, plastic additives, PVC thermal stabilizer | INTRODUCTIONPoly(vinyl chloride) (PVC) is a thermoplastic polymer obtained by free radical polymerization of vinyl chloride (VC) monomers. It is one of the top five general-purpose plastics in the world, it has many good physical and chemical properties, such as flame retardant, good water resistance, electrical insulation, acid resistance, alkali resistance, and so forth. [1] With its good performance, PVC has become the most commonly used plastic material in today's society, and is widely used in profiles, pipes, films, sheets, packaging materials, consumer goods. [2] Due to the poor thermal stability of PVC resin materials, aging, discoloration, and deformation will occur under high temperature processing conditions. The degradation of PVC will deteriorate the physical and chemical properties and mechanical properties of its products.

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The current research efforts in the plasticizer industry should focus on finding renewable biomass chemical feedstocks to synthesize non-toxic and effective bio-based plasticizers in order to adapt to the concept...

Composite molecular sieves, FAU/SBA-15, having core-shell structure were synthesized. The synthesized composite sieves were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), pyrolysis fourier transform infrared (Py-FTIR) spectroscopy, temperature programmed desorption spectra (NH3-TPD), UV Raman spectroscopy, nuclear magnetic resonance (NMR) and other techniques. XRD, SEM, TEM, N2 adsorption-desorption, mass spectrometry, NMR and EDS results showed that the composite molecular sieve contained two pore channels. Py-FTIR results showed that the addition of HY molecular sieves improved the acidity of the composite zeolite. The crystallization mechanism during the growth of FAU/SBA-15 shell was deduced from the influence of crystallization time on the synthesis of FAU/SBA-15 core-shell structured composite molecular sieve. HY dissociated partially in H2SO4 solution, and consisted of secondary structural units. This framework structure was more stable than its presence in the isolated form on the same ring or in the absence of Al. Thus it played a guiding role and connected with SBA-15 closely through the Si-O bond. This resulted in the gradual covering of the exterior surface of FAU phase by SBA-15 molecular sieves. The presence of SBA-15 restricted the formation of the other high mass components and increased the selectivity towards ethylbenzene.