JPH0563498B2 - - Google Patents

Description

[Detailed description of the invention]

(Field of Industrial Application) The present invention is a phenolic resin useful for applications such as architectural insulation materials such as ceiling materials, wall materials, and roofing materials, heat insulating materials for piping and heating devices, and kenzan for fresh flowers and plant nursery beds. The present invention relates to a method for producing a foam. (Prior Art) Generally, when obtaining a phenolic resin foam from a liquid phenolic resin, a resol type or benzyl ether type phenolic resin is used as the phenolic resin. As blowing agents, halogenated hydrocarbons such as trichlorotrifluoroethane (CFC-113), trichloromonofluoromethane (CFC-11), and dichloromethane, and hydrocarbons such as pentane and hexane are generally used. As additives, surfactants as foam stabilizers, flame retardants, neutralizing agents, etc. are used. As curing agents, organic acids or solutions thereof and inorganic acids are used. A method is known in which these raw materials are uniformly mixed, sprayed or poured into a mold, etc., and then foamed and hardened to obtain a phenolic resin foam. As blowing agents, trichlorotrifluoroethane (CFC-113), trichloromonofluoromethane (CFC-11), dichlorotrifluoroethane (HCFC-123), dichlorofluoroethane (HCFC-141b), dichloromethane, pentafluoropropyl alcohol, etc. When using halogenated hydrocarbons or their derivatives, these blowing agents have no flash point, making the manufacturing process safe, and their thermal conductivity as a gas is low. The body also has excellent insulation properties. However, when using CFC-113, CFC-11, etc. as a blowing agent, CFC-113, CFC-11, etc. are extremely safe compounds, so they reach the stratosphere without being decomposed in the troposphere, and are decomposed by ultraviolet rays in the stratosphere. These chlorine atoms decompose ozone in the stratosphere and cause depletion of the ozone layer, which is currently a worldwide problem as a cause of environmental destruction at the global level. Regulations on manufacturing methods and amounts used are already underway worldwide. For this reason, it is necessary to reduce the use of CFC-113, CFC-11, etc. in accordance with regulations, replace them with other blowing agents, and completely eliminate them. Also, as blowing agents, HCFC-123, HCFC-141b,
When dichloromethane or the like is used, these blowing agents have hydrogen atoms in their molecules and are easily decomposed in the troposphere, so their ability to decompose ozone in the stratosphere is small and the impact on the environment is small. However, as blowing agents for producing phenolic resin foams, it is difficult to obtain foams with uniform and fine cells using these alone.
If it is used in combination with CFC-113, pentane, hexane, etc., and the amount of HCFC-123, HCFC-141b, dichloromethane, etc. is not less than 50% by weight of the total blowing agent amount, it will have uniform and fine bubbles and excellent quality. It is difficult to obtain a closed foam. This is HCFC−
This is thought to be because the compatibility between 123, HCFC-141b, etc. and the liquid phenol resin is too good, and the boiling point is too low. Therefore, it is necessary to use a combined blowing agent as described above, and it is impossible to avoid the aforementioned problems caused by using CFC-113, pentane, hexane, etc. (Problems to be Solved by the Invention) The purpose of the present invention is to
Provides a method for producing superior quality phenolic resin foams, which makes it possible to reduce or eliminate the use of halogenated hydrocarbons, which have a large Ozone Depleting Potential, and significantly improve the problem of environmental destruction on a global level. It's about doing. (Means for Solving the Problems) The present invention provides a method for producing a phenolic resin foam from a liquid phenolic resin, a blowing agent, other additives, and a curing agent, in which a blowing agent containing tert-butyl chloride as a main component is used as a blowing agent. The present invention relates to a method for producing a phenolic resin foam, characterized by using the following. The liquid phenolic resin used in the present invention is not particularly limited, and may be a resol type phenolic resin obtained by reacting phenols and aldehydes in the presence of an alkaline catalyst, a neutral metal salt catalyst, etc. Examples include benzylic ether type phenolic resin obtained by reacting with. Other blowing agents that can be used in combination with tert-butyl chloride are not particularly limited, but include, for example, trichlorotrifluoroethane (CFC-113, etc.), trichloromonofluoromethane (CFC-11), dichlorodifluoromethane (CFC
-12), monochloropetafluoroethane (CFC-
115), dichlorotetrafluoroethane (CFC-
114 etc.), chlorodifluoromethane (HCFC-22),
Dichlorotrifluoroethane (HCFC-123 etc.),
Dichlorofluoroethane (HCFC-141, etc.), chlorodifluoroethane (CFC-142, etc.), dichlorodifluoroethane (HCFC-132, etc.), difluoroethane (HCFC-152, etc.), chlorotetrafluoroethane (HCFC-124, etc.), dibromtetra Fluoroethane (Halon 2402, etc.), Bromochlorodifluoromethane (Halon 1211), Bromotrifluoromethane (Halon 1301), Difluoromethane (HFC
-32), pentafluoroethane (HFC-125), tetrafluoroethane (HFC-134, HFC-134a
etc.), trifluoroethane (HFC-143a, etc.), heptachloropropane (HFC-227, etc.), dichloroethylene, chloroform, trichloroethylene, carbon tetrachloride, methyl chloroform, etc. are used. Further, the halogenated hydrocarbon derivatives used in combination are not particularly limited, but include pentafluoropropyl alcohol, trifluoroethanol, trichloroethanol, trifluoropropyl alcohol, and the like. Furthermore, hydrocarbons include, but are not particularly limited to, propane,
Butane, pentane, hexane, cyclohexane,
Petroleum ether etc. are used. Hydrocarbon derivatives are not particularly limited, but include ethers such as dimethyl ether, diethyl ether, dipropyl ether, and methyl ethyl ether, ketones such as dimethyl ketone, diethyl ketone, and methyl ethyl ketone, methyl alcohol, ethyl alcohol, and propyl. Alcohols such as alcohol are used. These halogenable hydrocarbons, hydrocarbons, and derivatives thereof can be used alone or in combination of two or more. The total amount of the blowing agent used is not particularly limited, but it is preferably 1 to 60 parts by weight, preferably 4 to 40 parts by weight, based on 100 parts by weight of the liquid phenolic resin. When using tertiary-butyl chloride and other blowing agents together as a blowing agent, there is no particular restriction on the proportion of their use; however, considering the aforementioned environmental damage problem and the quality of the obtained foam,
Tertiary butyl chloride accounts for 50% by weight or more, preferably 70% by weight or more of the total amount of blowing agents used. Further, when tertiary butyl chloride and other blowing agents are used together as blowing agents, it is also possible to add a stabilizer as necessary. As additives, known surfactants, flame retardants, neutralizing agents, fillers, and other additives can be added.
Hardening agents include phosphoric acid, phosphorous acid, hypophosphorous acid,
Inorganic acids such as pyrophosphoric acid, tripolyphosphoric acid, hydrochloric acid, and sulfuric acid; organic acids such as arylsulfonic acids such as phenolsulfonic acid, toluenesulfonic acid, xylenesulfonic acid, and benzenesulfonic acid; and alkylsulfonic acids such as methanesulfonic acid. However, it is not limited to this. Further, these curing agents can be used alone or in combination of two or more, and can be used as an aqueous solution, another solution, or a non-solution. The amount of this curing agent used is not particularly limited, but it is preferably 1 to 60 parts by weight, preferably 5 to 30 parts by weight, per 100 parts by weight of the liquid phenolic resin. In the present invention, a phenolic resin foam can be obtained by uniformly mixing the above-mentioned raw materials, and then spraying or injecting the mixture into a mold or the like and foaming and curing the mixture. The foaming hardening process can be performed at room temperature or in a heated atmosphere. When these raw materials are mixed in batches, a stirrer such as a disper is used, and when they are mixed continuously, a known multi-component mixing and foaming machine is used. Further, the mixed raw materials can be foamed and hardened in a mold, for example, and then removed from the mold to be made into a product, or further processed into a required shape to be made into a product. The mixed raw materials include soft facing materials such as kraft paper, aluminum hydroxide paper, asbestos paper, asphalt paper, calcium carbonate paper, aluminum kraft paper, iron foil, stainless steel foil, plastic film or sheet, steel plate, aluminum plate, etc. Injected between hard surface materials such as stainless steel plates,
It can also be made into products in the form of boards, panels, siding materials, etc. (Example) The present invention will be described in detail below with reference to Examples and Comparative Examples. Parts simply indicate parts by weight. Example 1 100 parts of phenol, 173 parts of a 37% formaldehyde aqueous solution, and 1 part of sodium hydroxide were charged into a reaction vessel and reacted at 90°C for 3 hours, followed by dehydration under reduced pressure to obtain a resol type liquid phenolic resin. To 100 parts of this resol type phenolic resin, 2 parts of silicone surfactant L-5421 (manufactured by Nippon Unicar) as a foam stabilizer and 10 parts of tert-butyl chloride as a foaming agent were added and mixed uniformly to prepare a premix component. 15 parts of a 65% phenolsulfonic acid aqueous solution was added to the mixture, stirred and mixed uniformly using a lab mixer, and a 300
After pouring into a mm aluminum mold and heating for 10 minutes, the mold was demolded to obtain a phenolic resin foam. The state of the cells in this phenolic resin foam was visually observed, and the density was determined by the method specified in ASTM D1622, the thermal conductivity was determined by the method specified in JIS A1412, and the compressive strength was determined by the method specified in ASTM D1621. Friability was measured using the method specified in ASTM C421. The results are shown in Table 1. Examples 2 to 7 and Comparative Examples 1 to 2 As shown in Table 1, phenolic resin foams were obtained in the same manner as in Example 1, except for changing the type and proportion of the blowing agent, and the quality was measured in the same manner. I went there.
The results are shown in Table 1. As shown in Examples and Comparative Examples, by using tert-butyl chloride as the entire amount or a part of the blowing agent, uniform and fine bubbles,
Phenolic resin foam with low thermal conductivity, high compressive strength, low flyability and low ODP

[Table] It is clear that the body can be obtained. (Effect of the invention) Tertiary butyl chloride used as a blowing agent in the present invention has a hydrogen atom in its molecule and is easily decomposed in the troposphere, so it is difficult to reach the stratosphere.
It decomposes in the stratosphere due to ultraviolet rays, releases hydrogen atoms, decomposes ozone in the stratosphere, and has little ability to destroy the ozone layer, so the problem of environmental destruction is also small. In addition, tertiary butyl chloride has compatibility with liquid phenolic resin and boiling point that matches the foaming and curing characteristics such as heat generation rate and gelation rate during the foaming and curing process of phenolic resin foam, so it produces uniform and fine bubbles. It is thought that a foam with excellent physical properties can be obtained. Therefore, by using tert-butyl chloride in whole or in part as a blowing agent, it is possible to significantly improve the quality of the prior art in many of the above-mentioned qualities.

Claims (1)

[Scope of Claims] 1. A method for producing a phenolic resin foam from a liquid phenolic resin, a blowing agent, other additives, and a curing agent, characterized in that tert-butyl chloride is used as the main component as the blowing agent. Method of manufacturing foam. 2. The method according to claim 1, wherein the blowing agent is tert-butyl chloride alone. 3. The method according to claim 1, wherein the blowing agent other than tertiary-butyl chloride is at least one selected from halogenated hydrocarbons, halogenated hydrocarbon derivatives, hydrocarbons, and hydrocarbon derivatives.