Formaldehyde absorptive reagent and preparation process thereof

Abstract

The present invention discloses a formaldehyde absorptive reagent and the preparation method; the weight match of materials of formaldehyde absorptive reagent includes: softened water: 0.9 to 1.7; phosphoric acid: 0.3 to 0.5; carbamide: 0.6 to 1.3; activator: 0.003 to 0.009. The formaldehyde absorptive reagent is prepared with the polymerization of phosphoric acid and carbamide with the help of the activator. The preparation method of the formaldehyde absorptive reagent of the present invention is easy and rapid, convenient and low in cost. When being applied with urea-formaldehyde resin adhesive, the excessive free formaldehyde is absorbed during the heat press, the formaldehyde absorption is remarkable and perennial without bounce. During the manufacture and the application, the formaldehyde absorptive reagent generates no toxin, bringing no harm to human and environment and meeting the environmental demands.

Description

technical field [0001] The invention relates to a preparation for eliminating harmful chemical substances and a preparation method thereof, in particular to a formaldehyde absorbing agent and a preparation method thereof. Background technique [0002] Urea-formaldehyde resin has many advantages such as low manufacturing cost, good adhesiveness, and color close to wood, making it the most widely used wood adhesive in the world. [0003] However, urea-formaldehyde resin glue is easy to release free formaldehyde, which affects human health. The problem of formaldehyde release from wood-based panels using urea-formaldehyde resin glue has attracted the attention of the whole world. Relevant researchers have made extensive and in-depth research on this. At present, there are several common methods to reduce the amount of formaldehyde released from wood-based panels at home and abroad: [0004] The first commonly used method is to modify the urea glue, that is, in the reaction of ...

AI Technical Summary

Problems solved by technology

However, the method of reducing the formaldehyde emission of urea glue by reducing the F / U molar ratio will bring some negative effects: the bonding strength of urea glue will be significantly reduced, especially the internal bonding strength of wood-based panels will decrease significantly, and it will affect the urea glue. glue curing speed

[0005] The method of modifying urea glue can also be added into urea glue by adding other kinds of glue such as melamine (Liu Yongdan, Hu Juliang, Analysis of factors affecting the amount of formaldehyde released from artificial wood panels, wood-based panel communication, 2001, 8 (9): 11 ~12; Lin Changzhen, Gu Jiyou, Research progress of melamine-modified urea-formaldehyde resin adhesives, Bonding, 2001, 22(5): 29-32; Wu Zhen, Guo Qing, Sun Jieyang, Li Hui, Environment-friendly urea-formaldehyde adhesives and their Preparation and Research of Wood-Based Panels, New Building Materials, 2007(4): 1~5), this method can effectively reduce the amount of formaldehyde released, improve the dimensional stability and water resistance of the panels, but will increase the cost of the panels

For example, if urea rubber is modified by adding melamine, if the amount added is 4%, the price of melamine is calculated at 7,000 yuan / ton, and the cost of urea glue per ton will increase by 280 yuan

[0006] The second method is to improve the hot-pressing process conditions of wood-based panels, by increasing the hot-pressing temperature of wood-based panels and prolonging the hot-pressing time, reducing the amount of formaldehyde released (Yang Fan, Xu Wen, Formaldehyde release in wood-based panels and its detection method, Forest Products Industry , 1997, 26(6): 39; Liu Yongdan, Hu Juliang, Analysis of the Factors Affecting the Formaldehyde Release of Artificial Wooden Panels, Wood-Based Panel Communication, 2001, 8(9): 11~12), but this method reduces the formaldehyde release The effect is not obvious enough, and prolonging the hot-pressing time and increasing the hot-pressing temperature will inevitably bring about the following problems: increase energy loss, reduce production efficiency, and increase product cost

The main problem caused by adding formaldehyde scavenger to urea glue is that it increases the production cost of urea glue and affects the curing speed of urea glue. In addition, the formaldehyde absorption effect usually only lasts for half a year to about a year, and the formaldehyde absorption effect is not long enough.

For example, the price of FC-5 formaldehyde scavenger produced by Dalu Zhenxing Co., Ltd. in Japan is 35,000 yuan / ton. If 1%-2% is added to the glue, the cost of urea glue per ton will increase by 300-600 yuan.