A kind of low-viscosity expandable phenolic resin and preparation method thereof

[0018] A low-viscosity expandable phenolic resin, comprising weighing raw materials by mass fraction: 100 parts of phenol, 48 parts of paraformaldehyde, 0.5 part of sodium hydroxide, 0.5 part of barium hydroxide, 10 parts of diluent, 1 part of urea, 5 parts of inorganic filler; the diluent is a mixture of water and alcohol, the mass ratio of water and alcohol is 3:1, the alcohol is one or more of ethylene glycol, diethylene glycol, and polyvinyl alcohol, and the inorganic filler includes One or more of aluminum hydroxide powder, talcum powder, and kaolin.

[0019] Its preparation method comprises the following steps:

[0020] (1) Vacuum pump 100 parts of molten phenol into the reaction kettle, add 48 parts of paraformaldehyde, 0.5 parts of sodium hydroxide, and 5 parts of diluent into the reaction kettle at one time, keep the reaction kettle in a state of equilibrium with the atmosphere, start stirring and Turn on the cooling water to cool the reaction kettle, and keep the t...

[0024] A low-viscosity expandable phenolic resin, comprising weighing raw materials by mass fraction: 100 parts of phenol, 55 parts of paraformaldehyde, 0.8 parts of sodium hydroxide, 2.8 parts of barium hydroxide, 16 parts of diluent, 3 parts of urea, 7 parts of inorganic filler; the diluent is a mixture of water and alcohol, the mass ratio of water and alcohol is 3:1, the alcohol is one or more of ethylene glycol, diethylene glycol, and polyvinyl alcohol, and the inorganic filler includes One or more of aluminum hydroxide powder, talcum powder, and kaolin.

[0025] Its preparation method comprises the following steps:

[0026] (1) Vacuum pump 100 parts of molten phenol into the reactor, add 55 parts of paraformaldehyde, 0.8 parts of sodium hydroxide, and 8 parts of diluent into the reactor at one time, keep the reactor in a state of equilibrium with the atmosphere, start stirring and Turn on the cooling water to cool the reaction kettle, and keep the temperature at 65°C for...

[0030] A low-viscosity expandable phenolic resin, comprising weighing raw materials by mass fraction: 100 parts of phenol, 58 parts of paraformaldehyde, 1 part of sodium hydroxide, 4 parts of barium hydroxide, 20 parts of diluent, 4 parts of urea, 10 parts of inorganic filler; the diluent is a mixture of water and alcohol, the mass ratio of water and alcohol is 3:1, the alcohol is one or more of ethylene glycol, diethylene glycol, polyvinyl alcohol, and the inorganic filler includes One or more of aluminum hydroxide powder, talcum powder, and kaolin.

[0031] Its preparation method comprises the following steps:

[0032] (1) Vacuum pump 100 parts of molten phenol into the reaction kettle, add 58 parts of paraformaldehyde, 1 part of sodium hydroxide, and 10 parts of diluent into the reaction kettle at one time, keep the reaction kettle in a state of equilibrium with the atmosphere, start stirring and Open the cooling water to cool the reaction kettle, and keep the temperatur...