JPH0515540B2 - - Google Patents

Description

[Detailed description of the invention]

(a) Industrial application field This invention relates to a method for producing a phenol foam composite. More specifically, the present invention relates to a method for producing a composite phenolic resin foam molding (phenol foam) useful for various cushioning materials, heat insulating materials, exterior panels, partition boards, etc. (b) Conventional technology The conventional method for producing phenol foam is to place a face material at the bottom of a mold, scatter and fill the surface of this face material with a powdered foamable phenolic resin composition, and then fill the surface with a spacer. A method is known in which a face material is placed and heated to foam and harden. On the other hand, a method is known in which a lightweight aggregate such as expanded plastic particles or perlite is mixed with a powdered foamable phenolic resin composition, and then the mixture is filled into a predetermined mold and heated to foam. There is. (c) Problems to be Solved by the Invention However, in such a manufacturing method, vibrations, shocks, etc. during work may cause the foamable phenolic resin composition powder to be dispersed unevenly or to settle into aggregates such as pearlite. The resulting laminate of phenol foam and face material has inconsistent quality due to variations in the density of the phenol foam, and also has problems with the adhesion between the face material and the phenol foam. In particular, when aggregate such as perlite was added to the foam layer, there were areas where the aggregate came into contact with the face material, causing problems in adhesion. The inventors of this invention conducted intensive studies to solve the above technical problem, and as a result, they came up with the idea of using a foamable phenolic resin composition by coating it on a surface material, and completed this invention. It came to this. (d) Means for Solving the Problems According to the present invention, there is provided a foamable phenolic resin composition in which one or both surfaces of the face material are composed of a phenolic resin initial condensate, a decomposable foaming agent, and a curing agent added as necessary. A foamable resin-coated plate is prepared, and at least one pair of the foamable resin-coated plate is covered with the foamable phenolic resin composition coating layer facing each other with an aggregate particle filled layer interposed therebetween. The foamed phenolic resin composition is placed in a mold and then subjected to conditions for foaming and hardening, thereby obtaining a composite in which the foamed phenol layer containing aggregate particles and the face material are integrated. A method of making a phenol foam complex is provided. In this invention, a face material coated in advance with a melt or solution of a foamable phenolic resin composition is used, and when this is used for foam molding, the molded product has many industrial advantages as described below. be done. Examples of the phenolic resin initial condensate used in this invention include novolac type and resol type phenolic resin initial condensates. Here, the novolak-type phenolic resin initial condensate is a so-called novolak-type phenolic resin known in the art that is obtained by reacting phenols and aldehydes in the presence of an acidic catalyst. means that polymerization can proceed further. This resin is generally solid at room temperature. On the other hand, the resol-type phenolic resin initial condensate is a so-called resol-type phenolic resin known in the art, which is obtained by reacting phenols and excess aldehydes in the presence of a basic catalyst, and is acid-cured. It means a substance that can undergo polymerization by using an agent and heating. Such resol-type phenolic resin itself is a liquid containing about 20% reaction water, but
This is further dehydrated (water is evaporated) to form a solid material (containing approximately 1% water), and this solid material is then pulverized to obtain the powdered resol type phenolic resin used in the present invention. Of course, a commercially available powdered resol type phenolic resin may also be used. The above phenols include, in addition to phenol,
3,5-xylenol, m-cresol, 2,5
-xylenol, 3,4-xylenol, 2,4
-xylenol, o-cresol, p-cresol, etc. The aldehydes include formaldehyde, paraformaldehyde, hexamethylenetetramine, furfural, acetaldehyde, acetals, and the like. A preferred precondensate for use in this invention is a phenol-formaldehyde condensate. The decomposable blowing agent in this invention means an inorganic or organic blowing agent that can be mixed with a phenolic resin initial condensate and decomposed to generate gas when heated and cured in the composition. Typical examples of these are N,
Organic blowing agents such as N′-dinitrosopentamethylenetetramine, benzenesulfonyl hydrazide, azobisisobutyronitrile, azodicarbonamide, paratoluenesulfonyl hydrazide, as well as sodium bicarbonate, ammonium carbonate, ammonium bicarbonate, and ammonium nitrite. ,
Examples include inorganic decomposition type blowing agents such as azide compounds (eg CaN ₆ ). All of these are in powder form. The amount of the blowing agent to be added is the required amount, mainly taking into account the desired final density of the blowing agent, but 1 to 50 parts by weight is appropriate for 100 parts by weight of the phenolic resin initial condensate; ~25 parts by weight is preferred. Hardeners are used in particular when novolak-type phenolic resin precondensates are used. This curing agent means a compound that can be decomposed by heating and can undergo a crosslinking reaction with the novolak type phenolic resin initial condensate.
Such a compound is, like formaldehyde, a compound used in phenolic resin molding by reaction with phenols, and is usually in powder form. Specific examples include hexamethylenetetramine, paraformaldehyde, methylal, dioxolane, trioxane, tetraoxane, trimethylolphosphine, S-triazine, and the like. The amount of the curing agent added is generally 1 to 30 parts by weight, preferably 4 to 15 parts by weight, per 100 parts by weight of the novolak type phenolic resin. In addition, it can be mixed with a cell regulator to further make cells finer and more uniform. Surfactants are used as bubble regulators, such as sorbitan fatty acid ester,
These include nonionic types such as silicon glycol copolymers and polyoxyethylene-based polyoxypropylene copolymers, and cationic types such as alkylamine salts. The foamable phenolic resin composition of this invention includes:
Flame retardants and other various additives such as fillers such as clay calcium carbonate, talc, and glass powder may also be added. The amount of these additives is preferably 100 parts by weight or less based on 100 parts by weight of the phenolic resin initial condensate. The solid resin composition of the present invention is usually prepared by kneading the above-mentioned phenolic resin initial condensate, a decomposable foaming agent, and, if necessary, a curing agent, using a heated roll or the like to uniformly mix the mixture, and then crushing it to form an external product. Diameter 1mm
Used in powder form: Of course, granules may also be used. The material of the face material in this invention is appropriately selected depending on the application, and examples include metal, inorganic, wood, plastic, fiber, or a laminate thereof. Examples of metals include aluminum, iron, steel, copper, etc.; examples of inorganics include glass, asbestos, gypsum, etc.
Calcium silicate, cement, etc., wood materials include veneer, paper, etc., plastic materials include polycarbonate, polyester, polyethylene, polyvinyl chloride, polypropylene, melamine resin, etc., and fibrous materials include woven fabrics, non-woven fabrics, etc. It will be done. The shape of the face material may be a planar shape or a curved surface shape. It may also be in the form of a hole. Planar objects include those that have one plane and those that have unevenness due to multiple surfaces (irregular shapes). Examples of the curved surface include corrugated and cylindrical shapes. The covering surface of the facing material preferably has a rough surface or an uneven surface because it is preferable that the facing material easily adheres to the foam material. As one example, it is preferable to use metal foil laminated with nonwoven fabric or the like. The thickness of the face material used in this invention is not particularly limited as long as it maintains its shape, and is appropriately selected depending on the application. The size of the face material used in this invention is not particularly limited, but a width of 3 cm to 3 m is suitable, and the length is appropriately cut depending on the purpose. The amount of the foamable phenolic resin composition coated on the face material in this invention depends on the desired thickness and density of the foam molded product, but is generally 5 g/m ² to 10 Kg/m ² with respect to the face material. is suitable, preferably between 10 g/m ² and 5 Kg/m ² . In addition, the coating amount of the above composition is 5g/m ² to 10Kg/
The thickness of the final foam corresponding to ^m2 is determined by the aggregate used in this invention (for example, perlite, shirasu balloon, glass balloon, glass foam granules, viscosity granules, viscous foam granules, cement granules, stone particles, synthetic resin particles, 2mm to 300mm depending on the presence of foamed synthetic resin particles, etc.
becomes. The foamable resin-coated plate-like body of the present invention is obtained by coating the foamable resin composition on the intended surface (one surface, both surfaces, or a portion thereof) of the surface material. Examples of methods for coating with a molten material include: 1) Spreading the composition powder on the surface material and then heating or hot pressing to melt it, or heating and melting it and pressing it with a roll or the like, 2) First applying the composition to a container. 3) The powder is melted in the air and simultaneously applied by spraying it using a thermal sprayer, etc. at the same time it is melted in the air. 4) The powder is kneaded with an extruder. 5) Warm the facing material to a temperature at which the powder melts and place the powder on the facing material.
6) Methods include melting the composition on a release paper and transferring it to the facing material while it is viscous. Method 5) is suitable when the surface material has an irregular shape or a curved surface. Further, method 6) is a method suitable for continuous formation. Further, as a coating method, there is also a method in which a foamable phenolic resin composition is dissolved in a solvent such as water, alcohol, toluene, etc., and then applied to the surface of the facing material. Furthermore, the surface of the facing material may be pre-moistened with a solvent such as water, alcohol, toluene, etc., and then the foamable phenolic resin composition may be sprayed and dissolved to coat the surface. The above-mentioned coating method is appropriately selected depending on the material and shape of the face material. The composition may optionally be used in the form of pellets, tablets or flakes. The use of the above-mentioned solvent is also preferred in that when the composition is used in a small amount, it can be uniformly spread and applied to the surface material. The melting temperature of the above composition is a temperature that is sufficient for melting and at which foaming does not proceed much (below 120°C).
It is. In order to adjust to this temperature, it is suitable to heat the heating source at a temperature of 150 to 200°C for a short time. Note that when the foamable phenolic resin composition is applied, it is desirable that the composition in the coating layer be in a foamed state of 50% or less. In the present invention, the foamable phenolic resin composition does not necessarily need to cover the entire face material, but may partially cover the surface material. For example, one in which only the periphery of the face material is covered is included. The above method provides a foamable resin-coated plate for use in the present invention. The manufacturing method of the present invention will be explained in detail below with reference to Examples, but the present invention is not limited thereby. (E) Examples Example 1 To 100 parts by weight of novolak type phenol-formaldehyde resin powder, 10 parts by weight of dinitrosopentamethylenetetramine as a blowing agent and 10 parts by weight of hexamethylenetetramine as a curing agent were added and kneaded with a heated roll. . Thereafter, it was pulverized to obtain a powdered resin composition. This foamable phenolic resin composition was a powder with a 100 mesh residue of 0.5%, a melting point of 81°C, and a gelation time of 76 seconds at 150°C. Next, as shown in FIG. 1, 116.0 g of this foamable phenolic resin composition was spread with a uniform thickness on the release paper 2 in a size of 250 mm x 250 mm, and this was spread on the second layer.
As shown in the figure, it is placed on a plate heater 3 heated to 150° C. for 1 minute to melt and coat. In this way, two foamable resin-coated plates coated with the foamable phenolic resin composition were made, one sheet was placed on the bottom as shown in Figure 3, and a sheet of 250 mm x 250 mm x
A 15 mm mold 4 is fitted with a 250 mm square phenol foamable resin composition 1. As shown in Fig. 4, into the cavity 5 made by the mold 4,
Pearlite (average 5.3mm) (product name Fuyolite,
(manufactured by Fuyolite Kogyo Co., Ltd.) 6 to almost the full (filling degree 100%), place another foam resin-coated plate with the coated side facing down, and place it on top of it, as shown in Figure 5. The lid 8 was placed between the press materials 7, and press heating was performed at 150° C. and a press pressure of 40 kg/cm ² for 15 minutes. The mold 4 was taken out from the press, and the phenol foam composite 9 was released from the mold 4. In the obtained phenol foam composite 9, pearlite grains 6 were uniformly dispersed throughout the phenol foam, and when cut, it was found that all the voids between the grains (porosity: 40%) were filled with phenol foam. Moreover, no defects were observed in the pearlite grains. Example 2 Same equipment as Example 1 except that the foamable phenolic resin composition coated on the release paper was changed to 10.7 g.
Twenty-five phenol foam composites were prepared under the same conditions. In all of the obtained phenol foam composites, pearlite grains were uniformly dispersed throughout the phenol foam, and when cut, all the voids between the grains were filled with phenol foam.
It could become a product. Comparative Example 1 106 g of the same foamable phenolic resin composition as in Example 1 was artificially mixed as homogeneously as possible into 1.5 grams of pearlite grains (trade name: Fuyolite No. 7, manufactured by Fuyolite Kogyo Co., Ltd.). Using the same release paper and equipment as in Example 1, 25 sheets were manufactured under the same conditions. Of these, 12 sheets had phenol foam filling the space between the pearlite grains and could be used as a product, but for the remaining 13 sheets, the phenol foam did not fill some of the spaces between the pearlite grains, so the pearlite separated. Therefore, it could not be used as a product. Example 3 The same equipment and method as in Example 1 were used except that the surface material was changed to aluminum foil with a thickness of 50 μm.
The obtained phenol foam composite was bonded with aluminum foil on both sides. This was subjected to a face material peeling test. Tabulate the results. Comparative Example 2 The same apparatus and method as in Comparative Example 1 were used, except that the face material was changed to the same 50 μm thick aluminum foil as in Example 3, and the foamable phenolic resin composition was changed to 120 g. The obtained phenol foam composite was adhered on both sides with aluminum foil, and when cut, it was found that all the voids between the particles were filled with phenol foam. Regarding this, a peeling test of the face material was conducted. The results are shown in the table. Example 4 The same equipment and method as in Example 3 were used except that the surface material was changed to non-combustible paper with a thickness of 150 μm. A surface material peeling test was conducted on the obtained phenol foam composite. The results are shown in the table. Comparative Example 3 The same equipment and conditions as in Comparative Example 2 were used except that the surface material was changed to the same noncombustible paper as in Example 4. The obtained phenol foam composite was adhered on both sides with non-combustible paper, and when cut, it was found that all the voids between the particles were filled with phenol foam. Regarding this, a peeling test of the face material was conducted. The results are shown in the table.

[Table] Measurement method: According to JIS Z-1528, 90° peeling method. Example 5 Cylindrical pellets with a diameter of about 2 mm and a length of about 4 mm made of the same foamable phenolic resin composition as in Example 1 at 305 g/m ² were spread uniformly on the upper surface of release paper, and 0.3 m /m of aluminum foil. Furthermore, 305 g/m ² of the above pellets were spread on the top surface of the aluminum foil, and release paper was further spread on the top surface. A press heated to 150°C applies a pressure of 10 kg/cm ² for 20 seconds. When the release paper on the upper and lower surfaces was removed, a double-sided foamable phenolic resin composition-coated aluminum foil in which both sides of the aluminum foil were coated with the foamable phenolic resin composition was obtained.
This phenolic resin composition is slightly foamed.
The double-sided foamable phenolic resin composition-coated aluminum foil was cut into 250 mm x 250 mm. 250mm×250mm×20
Place aluminum foil on the bottom of a mm mold, then spread perlite (Fuyolite No. 7, manufactured by Fuyolite Kogyo Co., Ltd.) to a depth of 10 mm, and then place double-sided foaming phenol resin coated aluminum foil on top of it. Next, spread perlite to fill the mold, place aluminum foil on top, and close the mold. It is then pressed at 150°C for 15 minutes under a pressure of 50 kg/cm ² . The obtained phenol foam composite has aluminum foil on the surface and center, and pearlite grains are uniformly dispersed throughout the phenol foam, and when cut, the voids between the grains are completely filled with phenol foam. It had been. Example 6 A surface material (trade name Showa Cloth, manufactured by Showa Aluminum Co., Ltd.) was sprayed with 5 c.c./m ² of water to form a foamable phenolic resin composition 256 similar to that of Example 1.
After uniformly coating the surface with an amount of g/m ² , it is left in a dryer at 65° C. for 3 hours. The resulting cloth coated with the foamable phenolic resin composition has good adhesion between the cloth and the foamable phenolic resin. This was press-molded in the same manner as in Example 1. Example 7 The same method as in Example 1 was carried out except that a paper honeycomb core material was used instead of perlite. When the obtained phenol foam composite was cut, all the voids were completely filled with phenol foam. Example 8 A non-combustible paper coated with 77 g/m ² of a foamable phenolic resin composition is used only for the bottom surface material, and an uncoated non-combustible paper is used for the top surface material. Nothing can be put inside the cavity. Example 1 other than this
It was carried out using the same equipment and method. The obtained phenol foam composite was a foam with a closed cell ratio of 65%. The density was 55Kg/ ^m3 . (f) Effects of the invention The foamable resin-coated plate used in this invention can be produced in advance to an appropriate size, transported while coated, and provided as a product that can be subjected to foaming when necessary. I can do it. The manufacturing method of the present invention using such a plate-like body exhibits the following remarkable technical effects. 1) The adhesion between the face material and the foam in the final foam molded product is superior to that obtained by filling a foamable resin composition on the face material, heating and foaming and curing it as in the past. 2) Even if the amount of phenol in the raw material used is reduced to about half compared to conventional methods, a molded product that can withstand use can be obtained, so phenol can be saved. For example, the amount required to be added to the final foam volume in the past was 80 to 100 g per volume, but only about 15 g per volume, 3) Since the face material is evenly coated, the foam becomes uniform; 4) Aggregate If this is done, there is no adhesion between the aggregate and the face material in simultaneous mixing and filling foaming, but with this invention, there is always adhesion between the aggregate and the composition, so a stronger adhesive molded product can be obtained.5) It is possible to perform foam molding on both sides of the face material at the same time, and 6) cavities due to gas accumulation are less likely to occur at the interface between the face material and the foam.

[Brief explanation of the drawing]

FIGS. 1 to 6 are configuration explanatory diagrams illustrating each step of the present invention, respectively. 1... Foamable phenolic resin composition, 2... Release paper, 3... Plate heater, 4... Mold, 5...
...Cavity, 6...Pearlite, 7...Pressed material, 8...Lid, 9...Phenol foam composite.

Claims (1)

[Claims] 1. Produce a foamable resin-coated plate-like body in which one or both sides of the face material are coated with a foamable phenolic resin composition consisting of a phenolic resin initial condensate, a decomposable foaming agent, and a curing agent added as necessary. ,
At least one pair of this foamable resin-coated plate-like body,
The aggregate particles are placed in a mold so that the foamable phenolic resin composition coating layer faces each other through the aggregate particle filling layer, and then subjected to conditions for foaming and hardening the foamable phenolic resin composition. A method for producing a phenol foam composite, characterized by obtaining a composite in which a foamed phenol-containing layer and a face material are integrated.