Nano silica-phenolic resin composite foam material and preparation method thereof

Abstract

The invention discloses a nano silicon dioxide-phenolic resin composite foam material and a preparation method thereof. The composite foam material is prepared from silicon dioxide nanoparticles, free phenol, free formaldehyde, a surfactant, a curing agent and sodium chloride as well as phenolic resin, wherein the silicon dioxide nanoparticles are bonded with phenolic resin by virtue of Si-O-C chemical bonds. The method comprises the following steps: firstly, ultrasonically dispersing a SiO2 sol in a formaldehyde solution or a mixed liquid of formaldehyde solution and paraformaldehyde to obtain a mixed solution; then, after mixing the mixed solution, phenol and an alkaline solution, and carrying out polymerization reaction to obtain resol in which the silicon dioxide nanoparticles are uniformly dispersed; then, firstly, carrying out acid neutralization and reduced pressure distillation on the resol; then, mixing and stirring the resol with a foaming agent and the surfactant to obtain mixed resin; and finally, adding the curing agent into the mixed resin and putting into a die to cure and foam to prepare a targeted product. The nano silicon dioxide-phenolic resin composite foam material disclosed by the invention can be widely applied to the fields such as building, aviation, refrigeration and the like commercially.

Description

technical field [0001] The invention relates to a composite foam material and a preparation method thereof, in particular to a nanometer silicon dioxide-phenolic resin composite foam material and a preparation method thereof. Background technique [0002] With the progress of society, after entering the 21st century, a series of fields such as construction, aviation, and refrigeration have higher requirements for thermal insulation, and the demand for thermal insulation materials has also been continuously improved. At present, although thermoplastic resin foam plastics such as polyethylene, polystyrene, and polyurethane have been very mature and have entered the market commercially, they are still not available due to problems such as flammability, high thermal conductivity, and poor water absorption of these insulating materials. Can no longer meet people's needs. [0003] Compared with the above thermoplastic resin foam materials, phenolic resin foam materials have the a...

AI Technical Summary

Problems solved by technology

At present, although thermoplastic resin foam plastics such as polyethylene, polystyrene, and polyurethane have been very mature and have entered the market commercially, they are still not available due to problems such as flammability, high thermal conductivity, and poor water absorption of these insulating materials. can no longer meet people's needs

[0003] Compared with the above thermoplastic resin foam materials, phenolic resin foam materials have the advantages of good flame retardancy, lower thermal conductivity, and good water absorption. Satisfactorily, the following situations often occur in the practical application of phenolic resin foam materials. One is that phenolic resin foam materials are easily damaged by slag when they are collided or squeezed during transportation and handling. When it is used as an external wall insulation material, it is easy to lose slag and damage during the process of plastering or pasting the external wall; thus resulting in a high defective rate of the phenolic resin foam material in actual use, resulting in an excessive application cost. High, which brings great difficulties to the popularization and application of phenolic resin foam materials

Images