The Exploration Of Synthesis Method For Aldehyde Substitued Polyphosphazenes And Research Of Modified Phenolic Resin

Phosphazene is kinds of compounds of chemical structure containing-P=N- unit, and because of it’s different kinds of side substituents, it show the different elasticity, high heat stability, flame retardant, high oxygen index, low smoke and excellent performance. Phenolic resin as human’s first kind of synthetic resin and first synthetic polymer compound has been industrialized compoundion more than one hundred years of history, however because of poor oxidation resistance, toughness, low carbon residue rate, its application in engineering field was limited. This article explored the synthesis of the aldehyde substitued polyphosphazene, and modified phenolic resin’s flame retardancy and toughness with different kinds of aldehyde substituted polyphosphazenes. The main work was as follows:1. Prepared poly(dichloridophosphazene) (PDCP) with ring opening polymerization in solution, and prepared sodium phenoxide, aldehyde phenoxide as nucleophilic reagents reacted with PDCP. Prepared mixed aldehyde and aldehyde substitued polyphosphazene.2. In the preparation of mixed aldehyde substitued polyphosphazene, we explored the method. And solved polyphosphazenes insoluble problem by adding nucleophilic reagent stepwise. Mixed aldehyde substitued polyphosphazene’s glass transition temperature was -2.47℃3. Explored the post-processing performance influence of the mixed aldehyde’s properties. Disposed mixed aldehyde substitued polyphosphazene with high temperature, the compound turned into insoluble.4. Prepared aldehyde substitued polyphosphazene successfully with 31P-NMR at-19.770 ppm, glass transition temperature 14.48℃, and the maximum weight loss rate of the thermal decomposition temperature was 400℃.5. Explored the best technology for liquid phenolic curing, and successfully prepared phenolic resin aldehyde substitued polyphosphazene modified phenolic compound. The aldehyde substitued polyphosphazene effectively improved the flame retardant properties and mechanical properties of phenolic resin.