Research On The Preparation Of LDHs Flame Retardant Paper By Polyelectrolyte Method

This paper proposed a flame retardant paper manufacturing technology with layered double hydroxide(LDHs) as the flame retardant. It was mainly discussed the optimal preparation conditions, as well as the pulp addition method and the polyelectrolyte method for LDHs flame retardant paper preparation.The main contents were as follows:(1) The influence factors of flame retardant paper manufacture were discussed by orthogonal and single factor experiments, in which the influence factors including the type, the mass concentration of the compound flame retardants and the p H value, the reaction temperature, the reaction time and the mass concentration of LDHs.(2) Three kinds of LDHs with different elements were synthesized by co-precipitation, and the flame retardant paper was prepared by pulp adding method. The experiment adjusted the polyelectrolyte material solution concentration and the combination order to design 4 kinds of polyelectrolyte units.(3) Using the method of polyelectrolyte electrostatic adsorption principle, the polyelectrolyte unit was adsorbed in pulp fiber surface, i.e. 20-layered polyelectrolyte films were deposited. The feasibility of Mg Al Zn La-CO3 LDHs as a flame retardant introduced into the paper by the polyelectrolyte method was studied in the research.By orthogonal test and single factor test, the effects of various factors on the preparation of flame retardant paper were discussed. The research results showed that the best preparation conditions were as follows: the mass concentration of melamine(MA) 10g/L, the p H value 7.0, the reaction temperature 50℃, the reaction time 15 min, and the mass concentration of LDHs 30 g/L. Among the investigated factors, the mass concentration of LDHs showed the most significant influence on the flame retardant paper, then the compound flame retardants,type and the reaction temperature, the mass concentration of the compound flame retardant, the p H value and the reaction time were insignificant. By the comprehensive analysis of the mechanical and the combustion properties of flame retardant papers, the 2#Mg Al Zn La-CO3 LDHs flame retardant paper showed better performance than the 1#Mg Al Zn Fe-CO3 LDHs and the 3#Mg Al Zn Ce-CO3 LDHs. With the polyelectrolyte method, the multilayer compound films of(LDHs/APAM/PEI/APAM)n were formed on the pulp fiber surface, and the fabricated paper showed that the mechanical properties were guaranteed and the flame retardant property was improved which met the requirements of GB/T 14656-2009.