HU195236B - Process for production of furane-resin-foams - Google Patents

Abstract

Non-corrosive hard foams and foam compsns. are prepd. from resol type phenolformaldehyde resins by adding to the resin 0.2-40.0 wt.% (in)organic blowing agent, 2-10 wt.% surfactant, opt. 10-150 wt.% power-station fly ash with a particle size distribution above 2000 Blaine and contg. 4-20 wt.% calcium oxide, 5-40 wt.% polymeric-acid catalyst and opt. based on the toal mixt. 5-30 wt.% reinforcing material. The mixt. is simultaneously expanded and cured. - Formaldehyde condensates of the urea complex of cresol-sulphonic-acid or of sulphuric-acid are pref. used as polymeric-acid catalysts. - Finely fibrous crushed rice husks and/or their ashes constitute the most useful reinforcing material.

Description

The present invention relates to a process for the preparation of low density, multipurpose phenolic resin based foams.

The production of phenolic resin-type foams has a long history today. The main reason for their widespread use is the relatively low cost of the raw materials required for their production and the increased heat and fire resistance of the finished foams, as well as their favorable physical and chemical properties.

Several monographs and technical books describe the preparation of phenolic resin foams in the technical literature. Most of them produce the foam from a phenolic formaldehyde condensate reacted in a 1: 1.2-3 molar ratio in a resole type, using a surfactant (blowing agent), a propellant and a crosslinking catalyst. As catalyst, T.H. Ferrigno: Rigid Plastic Foams (Reinhold Publishing Co., 1967.) c. his book mentions mineral acids and aromatic sulfonic acids as the most popular types of crosslinking catalysts. The K.C. Frish and J.H. In addition to the above catalysts, boron, boric anhydride, aluminum and ferric chloride, phosphorus pentaoxide, boron trifluoride ester derivatives, peroxides, cross-linking resol-type resins, edited by Saunders (Plastic Foams, Marcel Dekker Inc., 1973). peroxides, organic phosphoric acids with mineral acids and aluminum powder with Na hydroxide are mentioned as catalysts.

No. 333,844. U.S. Patent No. 4,400,151 to reduce the bulk density and residual acidity of phenolic resin foam as a catalyst in the reaction product of 1-50 wt.% arylsulfonic acid and a carbonic compound. .

No. 1,583,857. French Patent No. 4,268,198 uses a sulfaldenylurea formaldehyde complex for crosslinking unsaturated resole-type phenol-formaldehyde resin foams.

According to the latter, 1 mol of p-phenolsulfonic acid is reacted with 0.4-0.5 mol of urea and 0.62-0.68 mol of formaldehyde to give a polymeric acid catalyst having an acid number of 100-120 mgKOH / g, which is only 6070 ° C. It is capable of adequately foaming the phenolic resin by maintaining it at C. The resulting foam has a volumetric mass of 120 kg / m ³ and therefore enhances the efficiency of the catalyst by addition of inorganic acids, but when used suddenly results in cell rupture. In addition to the many open cells, it also has the disadvantage of having large holes at the bottom of the foam block.

It is an object of the present invention to provide foams in which the amount of closed cells is at least 80% and, in addition, its structure and properties meet all the requirements of the foam.

Our experiments have shown that a catalyst must be used which produces high uniformity foaming. One such catalyst was the one based on pmcresol sulfonic acid based polymeric acid, which was prepared by sulfonating 1 pmole cresol with 1.0-1.2 mole sulfuric acid at 90-110 ° C and then at 6080 ° C. 0.6-1.0 moles of urea and 0.21-0.28 moles of formaldehyde solution, on the one hand, and polymeric acid made from sulfuric acid, on the other hand, is prepared in a molar concentration of 1 mole of sulfuric acid at 65-75 ° C. Reaction with 0 molar urea followed by 0.35 molar formaldehyde solution.

The effect of improving the foam structure is provided by altered spherical conditions and changes in chemical structure.

It has been found that if the urea complex of the pm-cresol sulfonic acid mixture is formaldehyde condensed polymer (in short: KSR) or the urea complex of sulfuric acid in formaldehyde condensed polymer is used as catalyst in the preparation of phenol-formaldehyde resin foams, the crosslinking reaction is quenched compared to strong mineral acids, resulting in a uniform, mold-filling expansion of the foam in the available space, resulting in a finely divided, mostly porous, polyhedral cellular foam.

In addition, it has been found that power plant fly ash promotes the uniform dispersion of active agent vapor or propellant gas in the curing foam composition.

In our work, it has been found that, when 10-150% by weight of a phenol resin, from 5 to 20% CaO from coal-fired power plants with a particle size distribution above 2000 Blaine is added to the resin and the polymeric acid described above is added. foaming with the catalyst, the mechanical strength is significantly improved, the cooling strength of the material is increased and its combustibility is significantly reduced, and the residual acidity of the finished foam is also reduced, the latter effect being attributed to slow sorption of the fly ash.

The invention is to be further described below without limiting the scope of the invention by way of example.

EXAMPLE 1 Resol-g phenol-formaldehyde resin-type resin was mixed with 10 g of a Blaine-rated thermal power plant fly ash of 8.5% CaO, 2 g of hydrolyzed protein surfactant (Evegene UM), 15 g of methylene chloride, and 13 g of KSR catalyst (formaldehyde condensed polymer of urea complex of pmcresolsulfonic acid, acid number 310).

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For better and faster foaming, the blended mixture was placed in an oven at 80 ° C. The material foamed and solidified in 2-3 minutes. The resulting foam has a bulk density of 43 kg / m ³ . The volume of closed cells is 98%.

Example 2

The procedure of Example 1 was repeated at room temperature. The resulting foam dam ¹⁰ volumetric weight and the proportion of closed cells was identical to the above.

Example 3 For comparison, the procedure of Example 1.15 was repeated except that phenolic sulfonic acid based polymeric acid (UAG 3 catalyst, ÉMV Sajóbábony) was used. The foam volumetric weight of 50 kg / m ^3, the proportion of closed cells was ²⁰ back to 74%. Curing time 10 minutes.

Example 4

Following the procedure of Example 3, the foaming was carried out at room temperature. The resulting volume of foam ² tooth increased to 70 kg / m ³ and the proportion of closed cells decreased to 68%. After 15 minutes, the material was still ductile.

Example 5 30 g of resole resin was thoroughly mixed with 50 g of 3000 Blaine particle size thermal power fly ash (CaO content 12%), 3 g of water-soluble silicone oil (Silicon L540), 5 g of Freon 11, 35 g of 10 g SSR catalyst were added. (formaldehyde condensed polymer of urea complex of sulfuric acid, acid number 550). The foam obtained has a bulk density of 70 kg / m ³ ;

Example 6

The procedure of Example 1 was followed, except that 50 g of fly ash instead of 10 g and 18 g of KSR catalyst were used instead of 13 g. The resulting foam has a bulk density of 85 kg / m ³ . 45

Example 7

To the mixture prepared in Example 1 was mixed 8 g of finely crushed rice husk. The resulting foam has a compressive and tensile strength of approx. ⁵⁰ increased by 20%.

Example 8

To the mixture prepared according to Example 2 was added 8 g of crushed rice husk while stirring. 55 The resulting foam (increased compressive and tensile strength by 30%).

Example 9 To 20 g of resin resin was added 20 g grain size 3400 Blaine power plant fly ash with 10.5% CaO, followed by 2 g of polysiloxane foam regulator, 10 g of Freon 113 fuel and 8 g of SSR catalyst. After foaming, the product has a bulk density of 42 kg / m ³ .

Example 10

The procedure of Example 9 was repeated except that 6 g of Freon 11 was used as the propellant and 4 g of nonionic surfactant (Ipafor LN) was used as the surfactant. The resulting foam has a bulk density of 48 kg / m ³ .

Example 11 To a g of resol resin was added 50 g of a thermal power plant fly ash, 1.5 g of a sulfosuccinate surfactant (Solovet) and 2.2 g of NaHCO ₃ . After thorough mixing, 14 g of SSR catalyst were mixed into the system. The immediately expanding foam solidifies gradually. It has a bulk density of 72 kg / m ³ .

Example 12 0.4 kg Freon 11, 0.15 kg water-soluble silicone oil and finally 0.75 kg SSR catalyst were added to a kg of resole resin and mixed after 30 seconds. Volumetric mass after foaming is 30 kg / m ³ .

Example 13 To a kg of phenol-formaldehyde resin was added 0.4 kg of Freon 113, 0.15 kg of water-soluble silicone oil, followed by addition of 1.25 kg of KSR catalyst with stirring and stirring for another 30 seconds. Volumetric mass after foaming 28 kg / m ³ .

Claims (1)

Patent Claim Point The process is based on 4-30 wt.% Propellant based on phenol-formaldehyde resin, preferably methylene chloride or sodium bicarbonate, 3-6 wt.% Surfactant, preferably 20-100 wt. For the preparation of power plant fly ash containing 4 to 20% by weight of calcium oxide and optionally up to 16% by weight of reinforcing material, preferably crushed rice husk, characterized in that the foaming of the mixture is 15 to 36% by weight of p-cresol sulfonic acid condensed with formaldehyde of urea or sulfuric acid at 20-90 ° C for 1-30 minutes.