In this paper, a new heat stabilizer was prepared, which has shown not only excellence thermal stability, but also shown obvious oxidation resistance and anti-aging properties. This multifunctional heat stabilizer was prepared by organic acid, rare earth and thiourea. The lauric acid as best stuff was chosen from some normal fatty acid and lanthanum nitrate as most potent rare earth was picked up too. Using these raw materials, the best heat stabilizer was synthesized under this conditions of synthesizing at 80°C, reacting 40min, adding 1.0mol/L sodium-hydroxide for keeping PH at 8 and making certain the amount of raw material(lauric acid : thiourea : lanthanum nitrate) at the proportion as 4∶1∶1. The thermal stability was examined by the change time of Congo red, and the result proved this heat stabilizer having good thermal stability for up this time to 40min. When this rare earth stabilizer was joined into PVC, the PVC can keep its color not changing during 48h under ultraviolet radiation, and the tensile strength and elongation at break of the PVC added rare stabilizer changed more little under ultraviolet radiation compared with the traditional heat stabilizer system. So this rare earth heat stabilizer acting as a good heat stabilizer, anti-oxidant and anti-aging agent is a new multifunctional heat stabilizer.
In this article, the β–Sialon with average diameter size less than 20µm is prepared and researched by use of aluminum, silicon, and corundum at 1300°C holding temperature for 8h under nitrogen atmosphere. The preparation temperature of β–Sialon powder was optimized according to the results from the experiments that different aluminum and silicon reacted with pure nitrogen at different temperature. The reaction at the preparation of β–Sialon powder was discussed by thermodynamic calculation. The reaction mechanism was investigated by x–ray diffraction (XRD) and scanning electron microscope (SEM) was discussed in detail.
Precursor of nanosized TiO2 was prepared by alkoxide hydrolysis method. It was dried by common drying, far infrared drying, vacuum drying and supercritical drying before heat-treated at 600°C and 800°C. Influence of drying process and treatment temperature on the crystalline phase composition and photocatalytic activity were analyzed. The photocatalytic activity of the TiO2 dried by common and far infrared drying is higher than that of the TiO2 dried by vacuum and supercritical drying after treated at 600°C. The photocatalytic activity of the TiO2 dried by common and far infrared drying is lower than that of the TiO2 treated by the other two drying methods after treated at 800°C.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.