Phosphogypsum Utilization Part Ⅲ:as Adhesive Filler and Composite Materials

作     者：A.A.Hanna, Y.M.Abu-Ayana and S.M.Ahmed (National Research Centre, Dokki, Cairo, Egypt) 

出 版 物：《Journal of Materials Science & Technology》 (材料科学技术（英文版）)

年 卷 期：2000年第16卷第4期

页      面：439-444页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

主　　题：than PG PVAc Phosphogypsum Utilization Part 

摘      要：The aim of this work is to make use of phosphogypsum (PG) waste material, which is produced in phosphoric acid and phosphate fertilizer manufactures. A number of wood adhesive formulations based on polyvinyl acetate (PVAc) polymer and phosphogypsum as a filler have been prepared. using different percentages of phosphogypsum, ranging between 5-20 wt pct. The prepared formulations were tested for adhesion strength and compared with both natural and pure gypsum fillers. The results indicate that PG improves the adhesion strength when 5 wt pct added, and that may be due to filling the porous surface of wood with the fine particles of PG, as well as coating the particles of the filler (PG) with PVAc units. Also, a number of formulations based on urea-formaldehyde polymer have been prepared using phosphogypsum as an active filler in the ratio of 40-75 wt pct to prepare composite materials used for some decoration purposes and construction. Mechanical, physical, and thermal properties of these formulations were studied. Also, the activation energy was calculated. The results indicate that PG without acid hardener can be used for preparation of composite materials based on urea-formaldehyde between 40-63.64 wt pct for construction purposes in the humid atmosphere, while between 63.64-75 wt pct for decoration purposes. The improvement of the physical, mechanical and thermal properties of the composite material may be attributed to the simultaneous hydration hardening action of phosphogypsum and the presence of 0.8% P_2O_5. These effects act as an active hardener for urea-formaldehyde resin and accelerate the cross-linking and network formation reinforced by the fine dusty inorganic particles of PG. The advantage of this method is to prepare composite material gypsum-urea-formaldehyde, which achieves the utilization of large amount of PG, reducing the price of the main product phosphate, minimizing the pollution and producing new materials which possess high thermal resistanc