Preparation method of phenolic resin having narrow molecular weight distribution
A narrow molecular weight distribution, phenolic resin technology, applied in the direction of aldehyde/ketone condensation polymer adhesives, adhesive types, adhesives, etc., can solve the problems of increased cost, waste water pollution, complicated process, and inability to obtain molecular weight distribution, etc.
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
preparation example Construction
[0044] The preparation method provided by the present invention specifically includes: adding phenol, aldehyde accounting for 50% of the total aldehyde, to the equipment with a reflux device, adjusting the temperature to 40-45°C, adding an alkali catalyst, adjusting the temperature to 55-85°C, and constant temperature After 1-3 hours, add the remaining 50% aldehyde, measure the content of free aldehyde accounting for 3-5wt% of aldehyde compounds at a constant temperature of 55-85°C, quickly cool down to 48-50°C, add a low-molecular polymerization initiator, and rapidly cool down Below 25°C, settle for 24 hours, filter and dry.
[0045] The resin synthesized by the invention has a narrow molecular weight distribution, and the production process is simple and environment-friendly. The filtrate after filtration can be adjusted for wood bonding. Due to excessive aldehyde, the utilization rate of the phenolic compound is 100%, which protects the environment.
Embodiment 1
[0047] Put 500g of phenol and 500g of formaldehyde into a reaction flask equipped with stirring, thermometer and reflux device, adjust the temperature to 40°C, add 25g of sodium hydroxide, raise the temperature to 60°C and react at constant temperature for 2 hours, add 500g of formaldehyde, adjust the temperature to 50°C ℃, constant temperature until the content of free aldehyde accounts for 3.8wt% of aldehyde compounds, add urea, keep the temperature constant for 10 minutes, quickly lower the vacuum and reflux temperature to 12 ℃ while stirring, settle for 24 hours, filter and dry.
[0048] Detect the molecular weight distribution of the phenolic resin prepared by the present embodiment by gel solution chromatography GPC, the result is as follows figure 1 As shown, it can be seen that the molecular weight distribution Mw / Mn of the phenolic resin prepared in this embodiment is 1.05, which is smaller than the molecular weight distribution of the prior art. The phenolic resin wi...
Embodiment 2
[0050] Put 500g of phenol and 500g of formaldehyde into a reaction flask equipped with a stirring, thermometer and reflux device, adjust the temperature to 45°C, add 25g of sodium hydroxide, raise the temperature to 50°C and react at a constant temperature for 3 hours, add 500g of formaldehyde, and adjust the temperature to 45°C ℃, constant temperature until the content of free aldehyde accounts for 4.5wt% of aldehyde compounds, add urea, keep the temperature constant for 10 minutes, quickly lower the vacuum and reflux temperature to 12 ℃ while stirring, settle for 24 hours, filter and dry.
[0051] The molecular weight distribution of the phenolic resin prepared in this example was detected by gel solution chromatography (GPC). The molecular weight distribution Mw / Mn of the phenolic resin prepared in this example was 1.03, which was smaller than the molecular weight distribution of the prior art. The phenolic resin with narrow molecular weight distribution prepared by the pres...
PUM
| Property | Measurement | Unit |
|---|---|---|
| molecular weight distribution | aaaaa | aaaaa |
| molecular weight distribution | aaaaa | aaaaa |
Abstract
Description
Claims
Application Information
Login to View More 