KR20220084695A - Methods for manufacture of rigid urea resin foam with closed cell structure - Google Patents

Abstract

The present invention relates to a method for manufacturing a rigid urea resin foam having a closed cell structure. It relates to the manufacturing method in the order of the input process, the P6 molding process, and the P7 aging process.

Description

Method for manufacturing a rigid urea resin foam of a closed cell structure {Methods for manufacture of rigid urea resin foam with closed cell structure}

The present invention relates to a method for manufacturing a rigid urea resin foam having a closed cell structure having low thermal conductivity and absorption rate, low surface shrinkage, and high strength.

Styrofoam, which is often used as an insulator for interior and exterior materials, has poor heat resistance and causes casualties and material damage every year due to fires. Phenol foam has good heat resistance, but it smells of phenol and formaldehyde a lot, and glass wool is a glass fiber that is powdery and does not decompose in the human body when exposed to the skin or respiratory tract, so it is a carcinogen. are being classified.

There are problems with these various insulating materials, so a new insulating material is needed. Urea resin foam, which can be used as a new insulation material, has a relatively low raw material price, but there are many variables such as viscosity and molecular weight depending on the reaction conditions and types of additives when manufacturing the raw material resin. When foaming with air), there were disadvantages in that the surface shrinks or the absorption rate increases, and the strength decreases.

The present invention relates to a method of manufacturing a rigid urea resin foam having a closed cell structure having a low water absorption rate, low surface shrinkage, and high strength in order to solve the problems of the insulating material.

The urea resin foam has a very good flame retardant effect, but the mechanical strength is weak, so it crumbles easily, and the absorbency is great. Therefore, urea resin foam has been mainly used for filling the interior space of buildings.

To achieve the above object, by improving the urea resin used in the present invention, it is to present a manufacturing method capable of improving heat insulation, mechanical strength, removal of formaldehyde odor and water resistance.

The urea resin foam manufactured according to the present invention withstands high temperatures of 750° C. or higher, the flame is not generated and the fire is extinguished, the water resistance is closed cell, the absorption is low, the volume stability is good due to the small shrinkage, and the aging Because it removes moisture, there is almost no change in thermal conductivity depending on the period of use, excellent thermal insulation performance, and chemically stable, strong against weak acids, alkalis, oils and organic solvents, prevents corrosion of metal surfaces, and has no effect on insects, molds, etc. It can be used as an insulation material inside and outside the building.

[Figure 1] P1 urea resin manufacturing process
P2 methylolation process
P3 dispersant and deodorant input process
P4 blowing agent injection process
P5 hardener injection process
P6 forming process
It is manufactured in the order of the P7 aging process.
[Figure 2] is a product photo and SEM photo manufactured by [Figure 1]

The present invention relates to a method for manufacturing a rigid urea resin foam having a closed cell structure that is hard and does not break easily and has excellent mechanical strength. It has been mainly used as a sound absorbing material, but it is brittle and has weak mechanical strength, high absorbency, and the use of formalin used for polymerization of urea resin has a bad odor, so there has been a limit to its use so far. To solve this, a hydrocarbon-based blowing agent was used as a blowing agent, and a deodorant was used to remove the formaldehyde odor after manufacturing.

When described in detail in the order of [Fig. 1] showing the manufacturing method according to the present invention,

P1 urea resin manufacturing process

30~40wt% of formalin (Formalin, concentration 37%) and 60~70wt% of urea were added to the reaction tank, and caustic soda (NaOH) was added to adjust the pH to between 8-10 and reacted while stirring at 80-100℃. The process of manufacturing urea resin solution.

P2 methylolation process

After P1 reaction, in 85~90wt% of P1 urea resin solution, 10~15wt% of any one of polyethylene glycol, ethylene glycol, propylene glycol, and glycerin is added The process of methylolation (methylol).

P3 dispersant and deodorant input process

After P2 reaction, add 15-20 wt% of water to 73~83wt% of P2 urea resin, and dispersing agents Alkylbenzene sulfonic acid, Sodium Alkylbenzene sulfonate, Lauryl alcohol sulfonate 1~2wt% of alcohol sulfonic acid) is added and dispersed in an emulsion state. Here, as a deodorant, any one of β-Cyclodextrin, Zeolite, or Activated carbon powder Dispersant input and deodorant input process to put 1~5wt% of

P4 blowing agent injection process

After P3 reaction, in 95~97wt% of P3 urea resin solution, propane, ethyl chloride, butane, n-Pentane, dichlorotetrafluoroethane, A blowing agent input process of adding 3 to 5 wt% of any one of trichlorofluoromethane.

P5 hardener injection process

After P4 reaction, add 1-5 wt% of any one of phosphoric acid, formic acid, hydrochloric acid, and sulfuric acid as a curing agent to 95~99wt% of P4 urea resin solution and adjust the pH. The curing agent input process is set to 4.5~5.5 and stirred for 20~30 minutes.

P6 forming process

After the P5 reaction, the P5 urea resin solution is put into a certain mold and heated at a curing temperature of 50 to 60° C. for 10 to 20 minutes to form foaming.

P7 aging process

P6 Aging process to dry at room temperature after molding or to reduce moisture to 5% or less in a drying room at a temperature of 30~40℃.

It will be manufactured in the above order.

Hereinafter, when carried out in detail with reference to the accompanying drawings in order to achieve the above object as follows.

30wt% of formalin (concentration 37%) and 70wt% of urea were put in a reactor equipped with a cooler and agitator, and caustic soda (NaOH) was added to adjust the pH to 9.0, followed by reaction for 30 minutes while stirring at 85°C. To 90wt% of the urea resin solution, 10wt% of polyethylene glycol was added, methylolated while stirring for 20 minutes, and 15wt% of water was added to 80wt% of the methylolized resin solution and added as a dispersant. Add 1wt% of alkylbenzene sulfonic acid and disperse it until it becomes an emulsion. After dispersion, add 4wt% of β-Cyclodextrin and powder as a deodorant after dispersion and stir for 10 minutes, To 97wt% of the stirred resin solution, 3wt% of n-pentane (n-Pantane) was added and stirred for 5 minutes. Then, to 99wt% of the stirred resin solution, 1wt% of phosphoric acid was added, and the PH was adjusted to 4.5~5.5. After stirring for 20 minutes, the finished urea resin solution was placed in a fixed mold and heated to a curing temperature of 50° C. to form while swelling. After molding, it was prepared by drying at room temperature for 2 days.

30wt% of formalin (concentration 37%) and 70wt% of urea were put in a reactor equipped with a cooler and agitator, and caustic soda (NaOH) was added to adjust the pH to 9.0, followed by reaction for 30 minutes while stirring at 85°C. To 90wt% of the urea resin solution, 10wt% of ethylene glycol was added, methylolated while stirring for 20 minutes, and 15wt% of water was added to 80wt% of the methylolized resin solution and added as a dispersant. Add 1wt% of alkylbenzene sulfonic acid and disperse until it becomes an emulsion. After dispersion, add 4wt% of Zeolite powder as a deodorant, stir for 10 minutes, and then stir 97wt% of the resin solution. In, 3wt% of n-pentane (n-Pantane) was added and stirred for 5 minutes. Then, to 99wt% of the stirred resin solution, 1wt% of phosphoric acid was added, the PH was adjusted to 4.5~5.5, and after stirring for 20 minutes, the completed The urea resin solution was put into a certain mold and heated to a curing temperature of 50° C., it was molded while inflated, and after molding, it was dried at room temperature for 2 days.

The experimental results of Examples 1 and 2 (Table 1) were analyzed.

(Table 1)

Results of (Table 1)

The closed cell ratio of [Example 1] was good, the compressive strength and water resistance were good, and the formaldehyde concentration was detected to be less than 0.3 ppm of the exposure standard by adding a deodorant.

With the present invention, a rigid urea resin foam with low thermal conductivity and absorption rate, low surface shrinkage, and high strength can be manufactured and used as an insulation material for interior and exterior materials.

Claims (6)

30~40wt% of formalin (Formalin, concentration 37%) and 60~70wt% of urea were added to the reaction tank, and caustic soda (NaOH) was added to adjust the pH to between 8-10 and reacted while stirring at 80-100℃. A urea resin solution was prepared, and any one of polyethylene glycol, ethylene glycol, propylene glycol, and glycerin was added to 85 to 90 wt% of the prepared urea resin solution. A manufacturing method of methylolation by adding ~15 wt%. In 98 to 99 wt% of the resin solution prepared according to claim 1, alkylbenzene sulfonic acid as a dispersant, sodium alkylbenzene sulfonate, lauryl alcohol sulfonic acid A method of manufacturing by adding 1 to 2 wt% of any one of them and dispersing it in an emulsion state. [Claim 2] To 95-99wt% of the prepared resin solution, beta-cyclodextrin (β-Cyclodextrin), zeolite (Zeolite), activated carbon (Activated carbon) powder 1 to 5wt% of any one of the deodorant Way. [Claim 3] In 95 to 97 wt% of the prepared resin solution, propane, ethyl chloride, butane, n-pentane, dichlorotetrafluoroethane ( Dichlorotetrafluoroethane) and trichlorofluoromethane (Trichlorofluoromethane), any one of 3 ~ 5wt% of the manufacturing method. [Claim 4] In 95-99 wt% of the urea resin solution prepared according to claim 4, 1-5 wt% of any one of phosphoric acid, formic acid, hydrochloric acid, and sulfuric acid as a curing agent A method of manufacturing by adding , adjusting the PH to 4.5~5.5 and stirring for 20~30 minutes. [Claim 5] A method of manufacturing the mixed urea resin solution by putting it in a fixed mold and heating it at a curing temperature of 50 to 60° C. for 10 to 20 minutes to form a foam.

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