Modification technique of synthetic resin impregnated timber

Abstract

The invention relates to a technique for modifying synthetic resin impregnation wood and includes the following steps: 1. Preparation of impregnation solutions: liquid alkali is added into phenol at temperature of 42 to 45 DEG C and formaldehyde is added in succession at temperature of 65 to 80 DEG C, the mixture is kept for 3 to 4 hours at temperature of 70 to 85 DEG C and discharging is done after the temperature is reduced to less than 25 DEG C; 2. Impregnation: wood is added into an autoclave, and the vacuum is pumped in the pressure of 0.050 to 0.085Mpa, and the working solution of the impregnation solution is pumped in and pressure is added for 50 to 60 minutes in the condition of 0.7 to 0.9Mpa; 3. Solidification: the wood is placed into a baking oven, and the temperature rises to 90 DEG C after 3 to 4 hours and the wood is baked for 3 to 4 hours at temperature of 90 to 95 DEG C. The impregnation solution of the invention shortens the reaction time in synthesis process, improves the production efficiency, is stable in product quality and has good strengthening performance and processability; in the impregnation technique, the method for first reducing pressure and then increasing pressure is adopted, which causes the infiltration capacity of the synthetic resin to reach a stable amount and solves the problem of quality differences of the modified wood caused by different adsorption amounts of resin; compared with the solidification at temperature of 90 to 95 DEG C, the solidification at temperature of 100 to 105 DEG C causes the failure load and bending strength to increase, the wood not to embrittle and the processability to be good.

Description

technical field

[0001] The invention relates to a wood chemical treatment method, in particular to a treatment method of impregnating wood with a phenolic resin solution. Background technique

[0002] With the development of society, the consumption of wood is increasing year by year, while the available resources are decreasing year by year. Among the wood resources, some species are of poor quality, low density, low strength, brittle, and extremely perishable, so it is difficult to be used for industrial purposes. Wood, for which a resin impregnation method is often used, increases density, strength and resistance to decay.

[0003] At present, wood resin impregnation mainly uses phenolic resin solution. The original process is two-stage feeding, stirring for a certain period of time after adding alkali, then heating up, and two-stage heat preservation. The reaction time is long, the production efficiency is low, and the discharge temperature is high. After discharge, the ...

Examples

Embodiment 1

[0015] 1 Preparation of impregnation solution: add 14kg (149 moles) of phenol into the reaction kettle, raise the temperature to 42°C, add 2.4kg (14.9 moles) of 25% liquid caustic soda under stirring, heat up to 65°C within 55min after adding, At 78°C, add 25.4 kg (312.9 moles) of 37% formaldehyde successively within 80 minutes, keep at 80-85°C for 3 hours after adding, cool down to below 25°C and discharge.

[0016] Quality index: The appearance of 10% phenolic resin solution is a brown-red transparent liquid, the wavelength is 496nm, the thickness of the cuvette is 10mm, and its optical density is 1.298.

[0017] 2 impregnation: the density of 399 (kg / m 3 ) quality 6.4kg poplar plank (200×20×4cm) into the autoclave, airtight, connect to the vacuum system, vacuumize at 0.05MPa for 20min, then pump 20.0kg of the impregnating liquid working solution with a mass fraction of 12%, Change the vacuum system to a pressurized system, pressurize at 0.7MPa for 1 hour, and take out the ...

Embodiment 2

[0022] 1 Preparation of impregnating solution: add 14kg (149 moles) of phenol to the reaction kettle, raise the temperature to 43°C, add 2.6kg (16.4 moles) of 25% liquid caustic soda under stirring, and raise the temperature to 70°C within 70 minutes after adding. At 74°C, add 27.8 kg (342.7 moles) of 37% formaldehyde successively within 60 minutes, keep at 80-85°C for 3 hours after adding, cool down to below 25°C and discharge.

[0023] Quality index: The appearance of 10% phenolic resin solution is a brown-red transparent liquid, the wavelength is 496nm, the thickness of the cuvette is 10mm, and its optical density is 1.280.

[0024] 2 impregnation: the density 430 (kg / m 3 ) quality 6.9kg poplar plank (200×20×4cm) into the autoclave, airtight, connect to the vacuum system, vacuumize at 0.085MPa for 25min, then pump 21.0kg of the impregnating liquid working solution with a mass fraction of 15%, Change the vacuum system to a pressurized system, pressurize at 0.8MPa for 55 min...

Embodiment 3

[0029] 1 Preparation of impregnation solution: add 14kg (149 moles) of phenol to the reaction kettle, raise the temperature to 44°C, add 2.9kg (17.9 moles) of 25% liquid caustic soda under stirring, heat up to 70°C within 50min after adding, and heat up to 70°C within 50min. At 78°C, add 30.2 kg (372.5 moles) of 37% formaldehyde successively within 70 minutes, keep at 72-85°C for 3 hours after adding, cool down to below 25°C and discharge.

[0030] Quality index: The appearance of 10% phenolic resin solution is a brown-red transparent liquid, the wavelength is 496nm, the thickness of the cuvette is 10mm, and its optical density is 1.310.

[0031] 2 impregnation: the density 455 (kg / m 3 ) quality 7.3kg poplar wood plank (200×20×4cm) into the autoclave, airtight, connect to the vacuum system, vacuumize at 0.065MPa for 30min, then pump 22.5kg of the impregnating liquid working solution with a mass fraction of 10%, Change the vacuum system to a pressurized system, pressurize at 0...

technical field

[0001] The invention relates to a wood chemical treatment method, in particular to a treatment method of impregnating wood with a phenolic resin solution. Background technique

[0002] With the development of society, the consumption of wood is increasing year by year, while the available resources are decreasing year by year. Among the wood resources, some species are of poor quality, low density, low strength, brittle, and extremely perishable, so it is difficult to be used for industrial purposes. Wood, for which a resin impregnation method is often used, increases density, strength and resistance to decay.

[0003] At present, wood resin impregnation mainly uses phenolic resin solution. The original process is two-stage feeding, stirring for a certain period of time after adding alkali, then heating up, and two-stage heat preservation. The reaction time is long, the production efficiency is low, and the discharge temperature is high. After discharge, the ...

Examples

Embodiment 1

[0015] 1 Preparation of impregnation solution: add 14kg (149 moles) of phenol into the reaction kettle, raise the temperature to 42°C, add 2.4kg (14.9 moles) of 25% liquid caustic soda under stirring, heat up to 65°C within 55min after adding, At 78°C, add 25.4 kg (312.9 moles) of 37% formaldehyde successively within 80 minutes, keep at 80-85°C for 3 hours after adding, cool down to below 25°C and discharge.

[0016] Quality index: The appearance of 10% phenolic resin solution is a brown-red transparent liquid, the wavelength is 496nm, the thickness of the cuvette is 10mm, and its optical density is 1.298.

[0017] 2 impregnation: the density of 399 (kg / m 3 ) quality 6.4kg poplar plank (200×20×4cm) into the autoclave, airtight, connect to the vacuum system, vacuumize at 0.05MPa for 20min, then pump 20.0kg of the impregnating liquid working solution with a mass fraction of 12%, Change the vacuum system to a pressurized system, pressurize at 0.7MPa for 1 hour, and take out the ...

Embodiment 2

[0022] 1 Preparation of impregnating solution: add 14kg (149 moles) of phenol to the reaction kettle, raise the temperature to 43°C, add 2.6kg (16.4 moles) of 25% liquid caustic soda under stirring, and raise the temperature to 70°C within 70 minutes after adding. At 74°C, add 27.8 kg (342.7 moles) of 37% formaldehyde successively within 60 minutes, keep at 80-85°C for 3 hours after adding, cool down to below 25°C and discharge.

[0023] Quality index: The appearance of 10% phenolic resin solution is a brown-red transparent liquid, the wavelength is 496nm, the thickness of the cuvette is 10mm, and its optical density is 1.280.

[0024] 2 impregnation: the density 430 (kg / m 3 ) quality 6.9kg poplar plank (200×20×4cm) into the autoclave, airtight, connect to the vacuum system, vacuumize at 0.085MPa for 25min, then pump 21.0kg of the impregnating liquid working solution with a mass fraction of 15%, Change the vacuum system to a pressurized system, pressurize at 0.8MPa for 55 min...

Embodiment 3

[0029] 1 Preparation of impregnation solution: add 14kg (149 moles) of phenol to the reaction kettle, raise the temperature to 44°C, add 2.9kg (17.9 moles) of 25% liquid caustic soda under stirring, heat up to 70°C within 50min after adding, and heat up to 70°C within 50min. At 78°C, add 30.2 kg (372.5 moles) of 37% formaldehyde successively within 70 minutes, keep at 72-85°C for 3 hours after adding, cool down to below 25°C and discharge.

[0030] Quality index: The appearance of 10% phenolic resin solution is a brown-red transparent liquid, the wavelength is 496nm, the thickness of the cuvette is 10mm, and its optical density is 1.310.

[0031] 2 impregnation: the density 455 (kg / m 3 ) quality 7.3kg poplar wood plank (200×20×4cm) into the autoclave, airtight, connect to the vacuum system, vacuumize at 0.065MPa for 30min, then pump 22.5kg of the impregnating liquid working solution with a mass fraction of 10%, Change the vacuum system to a pressurized system, pressurize at 0...