Preparation, Structure And Properties Of Phosphonium Salts Pillared Layered Zirconium Salts

In recent years, Microbial disaster events occurred frequently, Using long-term antibacterial material is a safe and effective method of controling microbial propagation, Layered compounds usually conduct as carriers for preparing long-term composite antimicrobials. Clay was the main used layered compounds, Load antimicrobial active sub-stance including inorganic metal ions (silver, copper, zinc, and rare earth ion), organic cation (ammonium salt ions, phosphonium salt ions). But the clay were low purity, large particle and wide distribution, and its high viscosity make cleaning difficulties.it is necessary to probe the new intercalation materials which can overcome the shortcoming. In order to acquiring new antimicrobials pillared compounds.Zirconium bis-(monohydrogen orthophosphate) monohydrate (Zr(HPO4)2·H2O), also called layered a-zirconium phosphate (a-ZrP), are drawing increasing attention because of its advantages, good morphology structure, stability layered structure, high chemical stability, easy to exchange ion. Layer surface-OH group can exchange with corresponding groups according to the actual needs.Organic antibacterial exchange into a-ZrP may give novel antibacterial material with excellent antibacterial activity.The main goal of this study is to research and development a novel high temperature resistant and predominant antibacterial material based on ZrP. For this purpose, phosphonium salts with good heat resistance, high stability were employed as surfactants and intercalated intoa-ZrP to obtain new pillared compounds antibacterial material, The compounds with neat structure, good stability, high bacteriostatic efficiency.First of all, Layered zirconium salt (a-Zirconium Phosphate) has been prepared by hydrothermal method with Zirconyl chloride (ZrOCl2·8H2O) and concentrated phosphoric acid at 110℃. In traditional technology usually use fluoride as raw materials. The toxic chemicalspollute the environment and attack human beings. The method we used won't produce this effect.It is a very safe method. Secondly, phosphonium salts pillared layered zirconium salt (QPS-ZrPs) was prepared by introducing different phosphonium salts into layered zirconium salt (a-ZrP) through ion-exchange method, and the resulting QPS-ZrPs were characterized by FTIR, XRD, TEM, and TGA/DTG techniques. Minimum inhibitory concentration (MIC) was used to evaluate antibacterial activity. Also the Zeta potential, specific surface area and desorption content in water of QPS-ZrPs were determined.The results show that the phosphonium salt are intercalated into a-ZrP and the basal spacing of QPS-ZrPs is enlarged with the increase in phosphonium salt content and alkyl chain. SEM display zirconium salt displays flake shape with the particles adhered and interwinded each other, while the phosphonium salt pillared layered zirconium salt is formed of irregular shape.Phosphonium salt pillared layered zirconium salt (QPS-ZrPs) exhibit excellent thermal stability with the onset temperature of decomposition of higher than 250℃, Dodecyl tributyl phosphonium salt pillared layered zirconium salt (DDTB-ZrP) with 5.61 mass% of DDTB, shows the highest temperature resistant, the 5% weight loss temperature could be up to 320℃and the max decomposition rate temperature reaches to 384℃. Further analyses indicate that along with the increase in the content of phosphonium salt, the thermostability and the specific surface area of QPS-ZrPs decreases. but the antibacterial activity improves and the Zeta potential increases.Finally, the antibacterial activity of phosphonium salt pillared layered zirconium salt containing different phosphonium salt contents and chain length has been tested, For phosphonium salt pillared layered zirconium salt with the same phosphonium salt, the antibacterial activity improves with the increase of the phosphonium salt content. For the same content phosphonium salt, DDTBP-ZrP shows the best antibacterial activity. DDTBP-ZrP with 22.34 mass% of DDTB shows good antibacterial activity. After soaking in distilled water for 72 hours at 50℃, Only the mass fraction of 2.72% phosphonium salt released, the antibacterial activity of phosphonium salt pillared layered zirconium salt (QPS-ZrPs) did not decreased obviously.