JPH05132608A - Method for delaying ambient temperature curing of phenol resin mixture - Google Patents

Abstract

PURPOSE: To efficiently retard the ambient temperature hardening of a phenolic resin mixture useful for refractory articles, etc. by adding a specified retardant compound to a mixture of a phenolic resin with a magnesia aggregate.

CONSTITUTION: To a mixture of a hardening phenolic resin solution (A) a hardening phenolic resin solution in an amount enough to bond a magnesia aggregate during the heat hardening of a resin selected from the group consisting of a novolac, a resol having a pH of 4.5-9.5 and a viscosity of 100-10,000 cP at 25°C and a mixture thereof with a magnesia aggregate (B), desirably 0.1-6 wt.% a compound (C) which provides an aspartate, fluoride, bifluoride, citrate, malate, tartrate and phosphate anion or a tetraalkoxysilane, 2- or 4-chlorophenol or 2'- or 4'-hydroxyacetophenone is added to retard the ambient temperature hardening of the mixture.

COPYRIGHT: (C)1993,JPO

Description

Detailed Description of the Invention

This application is a continuation-in-part of our co-pending application 07/562206, filed August 2, 1990.

Our above application discloses compounds that retard the cure of phenolic resole resins mixed with a cure amount of light burned magnesium oxide or magnesium hydroxide, either alone or mixed with an ester functional hardener. Table 3 of the above patent application also relates to delaying the cure of periclase mixed with a phenolic resole and an ester functional hardener by the use of a retarder.

The present invention relates to methods and compositions useful in making and using ceramic and refractory compositions. More particularly, the present invention is a composition comprising hard-burned or dead-burned magnesia (both referred to herein simply as "magnesia agglomerates") and a curable phenolic resin with or without an ester functional hardener. Methods and compositions for retarding the cure of articles.
Such a delay can be imparted to the composition by, for example, 2'- or 4 '.
2- or 4-acetylphenol, which is also called -hydroxyacetophenone, tetraalkoxysilane,
Alternatively, it can be achieved by formulating certain compounds, such as compounds that provide fluoride, bifluoride, malate, tartrate, citrate or phosphonate anions to the composition.

Phenolic resins are widely used as refractory binders. However, they have certain drawbacks when used as binders for magnesia aggregates. Magnesia Aggregates and Hardenable
or a curable) phenolic resin mixture is relatively inert as compared to a mixture of light burned magnesium oxide and a phenolic resole resin.
However, when the magnesia agglomerates are mixed with the liquid phenolic resin, the wet mixture tends to cure at ambient temperature in a relatively short time. This reduces the amount of time the mix can be held until it is used, such as shaped into various products. The addition of the retarder of the present invention extends the processing time of such mixes by delaying the ambient temperature cure rate of the mix.

The problem of premature curing of magnesia aggregates when phenolic resole resins are used as binders has been recognized in the prior art. R. Yale (R.I.
US Pat. No. 4,657,950 (198) (198).
Apr. 14, 1995) solves such a problem of premature curing by using a modified resole resin.

T. Nishimura (T. Nisimura)
U.S. Pat. No. 4,539,343 (March 9, 1985).
In order to eliminate the reddish color of refractory materials and improve flexural strength, solid phenolic resins and magnesia-containing compositions are used at 25 ° C., such as salicylic acid, oxalic acid, malonic acid and phosphoric acid. It describes the use of compounds having a pKa of less than 9.5.

Gee. S. Borowski (GS Bo
U.S. Pat. No. 4,964,917 (October 23, 1990) to Rowski) et al. relates to a method of retarding concrete hydration by adding a calcium chelating agent to the concrete.

A. Etch. Gelber (AH Ger
Ber., U.S. Pat. No. 4,939,188 (1990).
March 7, 2000) relates to the use of lithium alkalizing agents in the curing of phenolic resole resins with ester functional curing agents for binding refractory aggregates such as magnesia.

M. Gillern
U.S. Pat. No. 4,264,671 (April 28, 1981) to a phenolic resole resin having a high formal group ratio and a low methylol group ratio for use in making glass laminates. The resin is manufactured under alkaline conditions and neutralized with acid. Weak acids such as citric acid are preferred.

Cassens, Juniors
Jr. No. 5,002,908 (1991).
March 26, 2013) relates to the use of phenolic resins for periclase (deadburned magnesia) bonding and the use of potassium borate to improve the processability of the composition. The patent states that impurities in borates should be avoided, especially that fluorine should be kept below 1%.

US Pat. No. 4,282,288 of Yoshino et al. (August 4, 1981) discloses a powdered phenolic resin as a binder and alumina, magnesia, silicon carbide, coke and zirconia. And / or at least one of silicon, phosphate and borate. The total amount of these additives should be up to 10 parts by weight with respect to 100 parts by weight of graphite.

US Pat. No. 4, to Lemon et al.
831,067 (May 16, 1989) describes the curing of alkali phenol resole resins with ester functional curing agents. Suitable alkalis are sodium hydroxide or potassium hydroxide or their mixtures with alkaline earth metal oxides or hydroxides, such as magnesium oxide.

Japanese Published Patent Publication No. 60/90251 (May 21, 1985) of Kyushu Refractory Co., Ltd. (May 21, 1985) discloses room temperature curing of a resole resin with magnesium oxide and ethylene carbonate.

The abstract of Soviet Patent Application No. 1316994 to Simonov et al. Relates to the improvement of properties of phenolic resin bound magnesia agglomerate refractory materials by adding chloride or bromide salts to the composition.

Japanese Patent Application No. 49026312 (74
March 8, 2012) and No. 78037884 (10 of 1978)
Dated 12th) and Japanese Patent Application No. 37884/19
The abstract of No. 78 (published on October 12, 1978 to Nippon Special Filter Media Co., Ltd.) relates to a refractory molding composition containing agglomerates, certain phenolic resins and phosphates.

Japanese Laid-Open Patent Publication No. 57051176 (assigned to Kawasaki Steel KK on Mar. 18, 1982) relates to a phenolic resin, a refractory aggregate and a phosphate additive.

M. Kei. Gupta (M.K. Gupt
a) U.S. Pat. No. 4,794,051 (December 27, 1988) describes (a) a phenolic resole resin; (b) an alkali metal oxide or hydroxide such as magnesium oxide or magnesium hydroxide, or A molding composition comprising a curing agent for silane; (c) filler; (d) lactone; and (e) fiber reinforcement is described.

International application No. PCT / GB89 /
No. 01526 (effective filing date, December 21, 1989)
Production of Phenol Resole Resin with Alkali Metal or Alkaline Earth Metal Compound as Basic Catalyst and Esterified Phenol as Ester Function Hardener Combined with Various Bases including Oxides of Magnesium and Calcium and Hydroxides Subsequent room temperature curing of such resins with resoles is disclosed.

Earl. Etch. Cooper (RH Co
Op., U.S. Pat. No. 2,869,191 (January 20, 59) relates to the use of active magnesium oxide for curing phenolic resole resins.

Earl. Etch. Cooper's U.S. Pat. No. 2,869,196 (Jan. 20, 59) relates to the curing of phenolic resole resins by the use of activated magnesium oxide and blast furnace slag as agglomerates.

US Pat. No. 4,473,654 to Stenders (September 25, 1984)
Combined with at least 5% free calcium oxide,
It relates to the bonding of refractory agglomerates such as periclase with lithium compounds such as lithium fluoride with or without a temporary binder. The binder is non-aqueous.

It has been found that ambient temperature curing of a composition comprising a magnesia agglomerate and a curable liquid phenolic resin, alone or in combination with an ester functional curing agent, can be delayed by the use of certain additives. Such a retarder additive includes tetraalkoxysilane in which each alkoxy group has 1 to 3 carbon atoms, and each alkoxy group has 1 to 3 carbon atoms.
Partially hydrolyzed tetraalkoxysilane, 2'-hydroxyacetophenone and 4'-hydroxyacetophenone (also called 2-chlorophenol and 4-chlorophenol), 2-chlorophenol and 4-chlorophenol, and the compositions and mixtures above. To aspartate, fluoride, fluoride, malate, oxalate, tartrate, citrate, phosphonate and phosphate anions. The compositions of the present invention are useful in the manufacture of various refractory materials such as ceramics, such as refractory bricks, castable shapes, ramming mixes, and impregnated refractory products.

In one aspect of the invention, a binder-aggregate composition is provided. The binder-aggregate is (a) a magnesia agglomerate; (b) a curable phenolic resin solution in which the resin is present in an amount sufficient to cure or reduce the mixture stream when left at ambient temperature; and (c) optional. , A mixture of ester functional hardeners and conventional additives used in refractory and ceramic compositions. The resin is preferably present in an amount sufficient to bind the aggregates during thermosetting of the resin.

In another aspect, the present invention provides a method of making a binder-aggregate composition which comprises mixing the components used in the binder-aggregate composition described above. Preferably, this mixing results in a moist, moldable composition.

In yet another embodiment, the binder-aggregate composition of the present invention comprising a phenolic resole resin together with a magnesia agglomerate is molded into a desired compact and the compact is allowed to stand at ambient temperature. The required ambient temperature intensity [also called green intensity] can be developed.

Yet another aspect of the present invention involves carbonizing the resin binder to form a refractory body by thermosetting the molded body and optionally heating it at an elevated temperature.

Extending mix life and processing time with the retarder of the present invention may facilitate refractory and infrequent production of ceramic mixes and / or production of larger batches of mixes to enhance productivity. it can. Retardants can extend the ambient temperature process life of the curable composition and allow the composition to be molded into the desired shape. further,
Moldings made from these mixes often show improved strength. The benefits of manufacturing refractory bricks are:
Especially advantageous on hot summer days. As the resin progresses in the cure direction in the uncompressed mix, complete drying of the mix occurs which results in a room temperature green low strength brick.
The use of the binder-aggregate material of the present invention containing a retarder suppresses or prevents this problem.

Phenolic Resin The phenolic resin can be a novolac solution, a resole solution, a novolac in resole solution, or a mixture thereof. The solid phenolic resin in contact with the magnesia agglomerates has the problem solved by the present invention, namely the
Does not cause premature curing of the aggregate mixture. Therefore, a solvent for the phenol solids is present in the binder-aggregate mixture of the present invention.

The phenol resol resin solution usable in the present invention is a phenol formaldehyde resin solution or
Phenol is, for example, cresol, resorcinol, 3,
5-Xylenol, partially or completely replaced by one or more phenolic compounds such as bisphenol-A or other substituted phenols, the aldehyde moiety being completely replaced by a phenol reactive aldehyde such as acetaldehyde, furaldehyde or benzaldehyde. A phenol formaldehyde resin solution that can be replaced.

The resole resin is thermosetting, that is, it forms an infusible three-dimensional polymer on heating, typically phenol in the presence of an alkali or alkaline earth metal compound as a condensation catalyst. And a 1 molar excess of a phenol-reactive aldehyde. Typically, the resole resin has a molar ratio (phenol: formaldehyde) within the range of about 1: 1 to 1: 3.
It is a phenol-formaldehyde resin produced by the reaction of phenol with formaldehyde at. Preferred molar ratios for use in the present invention range from about 1 mole of phenol to 1 mole of aldehyde to about 1 mole of phenol to 2.2 moles of aldehyde, especially phenol to aldehyde from 1 to 1.2 to 1: 2. Is. The phenol resole resin is usually in an aqueous solution state. The preferred phenolic resole resin used in the present invention is less than about 1%,
It preferably contains up to 0.5% by weight of soluble sodium or potassium.

Resols are made by a variety of condensation catalysts. These catalysts include alkali metal and alkaline earth metal oxides and hydroxides, quaternary ammonium hydroxide, and ammonia and organic amines. It is preferred to use retarders that are completely soluble in the phenolic resin and stable. In such a case, it is advantageous to store the phenolic resin and the retarder in a storage, especially when the phenolic resin is a resol solution. In less preferred systems, some of the retarder is evenly dispersed in the phenol solution as a fine powder.
Most unfavorable is when some of the retarder forms a precipitate which settles during storage. Alternatively, the retarder can be added to the binder-aggregate mixture or to the aggregate prior to addition of the binder.

The preferred catalysts for the resole formation of the present invention are potassium hydroxide and amines as they give little or no insoluble products upon addition of water soluble fluoride or bifluoride salts or organic acid retarders. Specific examples of amine catalysts include triethylamine; ammonia; and hexamethylenetetramine. Alkaline earth metal ions (Ca ⁺⁺ , Mg ⁺⁺ ) produce insoluble fluoride or bifluoride salts or insoluble salts of organic acid retarders. Similar results with alkaline earth metal ions are obtained with other divalent metal condensation catalysts. Soluble sodium in the resole is also not preferred, as sodium fluoride and the polysodium salts of malic acid, tartaric acid and citric acid are often insoluble in the preferred resole of the invention. Although soluble lithium in the resole is sufficient for use with organic acid retarders, it is preferred for use with fluoride or bifluoride because lithium fluoride has low solubility in water for the resole or this substance. Absent. Tetraalkylsilanes are preferably not added to the resole resin because of the improper hydrolysis that occurs due to the presence of water in the resin. However, if a solution of resin and retarder is used within a few hours after settling, some instability of the resin and retarder mixture is acceptable. Based on physical compatibility, the preferred system used a retarder to provide the composition with a fluoride or bifluoride anion, or citric acid, malic acid, tartaric acid or mixtures thereof as a retarder,
It is a potassium-catalyzed resol.

The pH of the phenolic resole resin used in the present invention is generally in the range of about 4.5 to 9 or 9.5, with a pH of 5 to 8.5 being preferred. The molecular weight of the resin is in the range of about 200 to 3,000 weight average molecular weight, with 300 to 1,000 being preferred. All others with equivalent or higher molecular weights and lower free phenol contents give rise to short ambient temperature gel times or set times, enhancing the strength development by the resole resin. Weight average molecular weight is measured using gel permeation chromatography, phenolic compounds and polystyrene standards. The sample to be molecular weight measured is prepared as follows: A resin sample is dissolved in tetrahydrofuran, made weakly acidic with 1N hydrochloric acid or sulfuric acid, and dried over anhydrous sodium sulfate. The salts formed are filtered off and the supernatant liquid is processed through a gel permeation chromatograph.

The resin solids content in the resole resin solution varies over a wide range, such as in the range of about 50-60% by weight of the phenolic resole resin. Preferably, the resin solids are about 50-80% by weight of the phenolic resole resin.
The range is. The viscosity of the resin is about 100 at 25 ° C.
It can vary over a wide range, such as the range of 10,000 cps. Preferably, the viscosity is about 250-5,000 c
It is within the range of ps. Viscosity measurements here are stated in centipoise (cps) measured with a Brookfield RVT viscometer at 25 ° C or by Gardner-Holt viscosity at 25 ° C. Specific gravity of the Gardner-Holt viscosity described in centistokes (generally 1.
Multiply by 2) to get the cps at 25 ° C.

The amount of free phenol in the resole resin can vary over a wide range, for example about 5-15% (BOR) based on resin weight. Increasing the amount of free phenol also increases the room temperature mix life of the curable binder-aggregate composition.

The liquid portion of the resole resin is water or water in combination with free phenol and optionally a non-reactive solvent. Solvents other than water include alcohols having 1 to 5 carbon atoms, diacetone alcohol, glycols having 2 to 6 carbon atoms, glycol monomethyl, dimethyl or butyl ether, low molecular weight (200 to 600) polyethylene glycols and their methyl ethers, carbon number. 6-15 phenols, phenoxyethanol, ethyl acetate, butyl acetate,
It is selected from propylene glycol, dipropylene glycol, methyl ethyl ketone, methyl isobutyl ketone, for example tetrahydrofuran and cyclic ethers such as m-dioxolane, and the like.

The typical water content of the resole resin used in the present invention is in the range of about 3 to 20% by weight of the resin (B
OR). Preferably, the water content of the resole resin is about 3-15.
% BOR (based on the amount of resole resin). Apart from the water in the as-produced resin, additional water can be mixed into the resin itself or into the binder-aggregate composition. The total water content in the binder-aggregate composition is preferably about 0.5.
Within the range of 5 wt%. Increasing the water content of the resin or the total water content in the binder-aggregate composition decreases the ambient temperature mix life of the binder-aggregate composition.

Novolak Resin The novolak resin is used as a liquid solution when used alone as a phenol resin, and as a liquid or solid when used in combination with a resole resin.

For use in the present invention, a novolak has about 3 parts.
It has a molecular weight of 00-3,500. Solvents used for dissolving novolak include ethylene glycol, furfuryl alcohol, diacetone alcohol, glycol ether acetate, glycol ether and mixtures thereof, and for example, methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, etc. Such as lower alcohols. The preferred novolac solids are about 50-70% by weight of the novolac solution. The preferred viscosity of the novolac solution is from about 2,000 at 25 ° C.
It is 6,000 cps. However, it is also possible to add ground or finely divided novolacs to the resol solution for the formation of the binder-aggregate composition.

Since the novolak resin is a resin which is produced with a shortage of aldehydes, when it is used alone, it is usually cured unless a curing agent such as hexamethylene tetraamine is added together with heat for heat curing. It is impossible. Novolac resin is generally defined as an acidic resinous reaction product of a phenolic substance and an aldehyde and for practical purposes does not cure or convert to an insoluble, infusible state when heated, but remains soluble and meltable. ..

The term "novolak" as used herein refers to a phenolic substance, such as phenol, cresol, which has been reacted with formaldehyde or other reactants used commercially for the production of novolac, such as benzaldehyde, furaldehyde, acetaldehyde and acetone. A novolak resin containing xylenol or a mixture thereof,
It means a polymer, a copolymer, a terpolymer or a mixture thereof. The novolak resins useful in the present invention have a formaldehyde: phenol molar ratio of about 0.5: 1 to about 0.1.
In the range of 9: 1, preferably about 0.6: 1 to 0.8: 1
And the phenolic substance is phenol, o-,
It is selected from m- and p-cresol, xylenol, and mixtures thereof. Preferably, the novolac resin is made by the condensation of formaldehyde with phenol at a pH of less than about 4, more preferably less than about 2.

Hexa and / or other methylene generators such as formaldehyde or paraformaldehyde can be added to the novolac-containing binder of the present invention. When used, hexa is added at a level of about 4 to about 15%, preferably about 5 to about 10%, based on the weight of total novolac phenolic resin. However, it is also possible to cure novolaks in the presence of resoles, since resoles use high molar ratios of formaldehyde and produce excess methylol groups, some of which can react with novolaks. If the binder-magnesia aggregate does not contain resol, the amount of calcium oxide in the magnesia aggregate is
It is preferred to be 1.5-4% by weight of the magnesia agglomerate, as the hardening rate of the binder-agglomerate increases with increasing calcium oxide content.

The composition of the present invention may use a blend of a novolac component and a resole component. By "component" herein is meant an individual resin of a blend, mixture, reaction product, or other resin combination containing the relevant novolac or resole. Such resin binders also have the desirable properties of low thermal conductivity, high dimensional stability and abrasion resistance. When the curable composition has both a resole binder and a novolac binder, it is preferred that about 1 to 4 parts by weight of resole be present per part of novolac. In such cases, it is also preferable to add powdered novolac to the resole resin or binder-aggregate mixture.

The amount of resin used in the binder-aggregate mixture is
In the case of a resole to bind the agglomerates during ambient temperature cure, or to reduce the fluidity of the mixture if novolac is used alone at ambient temperature, or the phenolic resin is a resole, novolac or mixture thereof. In some cases, the amount is sufficient to bond the mixture during thermosetting. Therefore, the amount of resin based on the agglomerates in the binder-agglomerate mixture is about 3 to 15 wt% resin based on the weight of the magnesia agglomerates, especially about 3 resin based on the weight of the magnesia agglomerates. ~ 8% by weight. The "resole" used in the present invention is a solution of a phenolic resin, even if it is called a "solution" hereinafter, and the "novolak" is a solid.

Magnesia Aggregates The magnesia aggregates can be either dead burned magnesia or hard burned magnesia. Hard-burned magnesia or dead-burned magnesia agglomerates will be simply referred to herein as magnesia agglomerates. Deadburned magnesia is sometimes called deadburned magnesite, refractory magnesia or periclase. In the refractory field, the terms "deadburned magnesite" or "deadburned magnesia" are used interchangeably to refer to a good, stable, dense, highly crystalline periclase product used in the manufacture of refractory bricks and the like. Used for. Such magnesia products are available from Martin Marietta Magnifica Species Company.
esia Specialties Company)
From MagChem Magnesium Oxide
It is available under the name of Products).

The reactivity and surface area of magnesium oxide (magnesia) are very different depending on the method used to make magnesia. These magnesia products are made by calcining magnesite (MgCO ₃ ) or magnesium compounds such as hydrates or chlorides at various temperatures. Magnesium oxide light burn de grades are prepared by calcining at a temperature within the range of about 100 ⁰ F. to about ^{1800 0 F (871 ℃ ~982 ℃} ). Hard-burned magnesia or dead-burned magnesia agglomerates are produced by firing at substantially elevated temperatures. Therefore, hard-burned magnesia or dead-burned magnesia agglomerates are produced by firing at temperatures above 280O ⁰ F (1540 ° C). In one reference,
That is, Kirk-Othme
r) “Encyclopedia of Chemical Technology (Encyclopedia of Chem
ical Technology ”[John Wiley & Sons (John Wiley & S
Ons), NY, 1982], vol. 20, p. 8, refractory material, this reference refers to dead burned magnesite 1
Hard-burned magnesia and dead-burned magnesia agglomerates appear to be treated the same, since they are said to be obtained by calcination of naturally occurring magnesium carbonate at 540-2000 ° C. However, for the purposes of this application, MagChem Magnesium Oxide Grade and Uses (MagChem Magne
siumOxide Grades and Use
firing temperature is described in the booklet of the Martin Marietta Magnesia Specification dial Tees Company s) made name used, according to this publication, a hard burn de grade about 2800 ⁰ F~3000 ⁰ F (1540~16
Manufactured by firing at a temperature in the range of 49 ° C.), the dead burn de grade magnesium oxide 4000 ⁰ F
It is fired at a temperature above (2204 ° C.). There are also differences in the surface area of various magnesia. Therefore, light burned magnesia has a surface area of about 10 to 200 m ² / g or more. Hard-burned magnesia and dead-burned magnesia have surface areas of about 1 m ² / g or less than 1 m ² / g.

Commercially available magnesia agglomerates generally have about 91% to more than 99% MgO, preferably about 96% to more than 99% MgO and less than 4% by weight CaO as major impurities. It is then analyzed and preferably the magnesia agglomerates contain up to 3.50% CaO. As the amount of quicklime (CaO) increases, the mix life in binder-magnesia aggregates decreases. Specific examples of suitable hard-burned magnesia agglomerates include 98.2% MgO content, 0.25% burn loss, 0.
Magchem 10 with 90% CaO and small amounts of other oxides
96% of this product, including -40, has -40 US sieves with a median particle size of 30 microns and a surface area of less than 1 m ² / g.

For use in refractory compositions, the magnesia particles are ground and sorted into various fractions. A typical mixture of coarse, medium, and fine particle fractions suitable for obtaining high bulk density and low porosity, such as for use in making refractory products useful in basic oxygen process furnaces, is Having a Tyler standard screen size such as: 30-35% 4 mesh pass, 10 mesh hold; 30-40% 6 mesh pass, 28 mesh hold; and 30-35% ball mill Fine particles (100
Less than mesh). The magnesia agglomerates used in the present invention include about 10 to 25% of such agglomerates, which are ground to a powder.

The term "room temperature cure" is about 60-90.
⁰ F, binding agents of the invention in particular a temperature of about 65-80 ⁰ F - means curing of the aggregate composition. However, the use of retarders in the methods and compositions of the present invention is for example 60 to 110 ⁰
Delays curing at low and high temperatures, such as F,
Such temperatures are referred to herein as ambient temperatures. Gelling or curing of the resole resin at ambient temperature even in the absence of magnesia aggregates is the first step to curing. Nevertheless, when the novolaks come into contact with the magnesia agglomerates at ambient temperature, there is an increase in viscosity, reduced flow or easy cure of the binder-aggregate composition of the present invention. In addition to ambient temperature cure, the binder-aggregate composition of the present invention is also heat cured after ambient temperature cure, or heat cured prior to such cure. As used herein, the term "heat cure" refers to curing the composition at a temperature of at least 170 ⁰ F (77 ° C), such as up to 248 ⁰ F (120 ° C), and generally at a temperature of at least 212 ⁰ F (100 ° C). Means

Ester Curing Agent The ester functional curing agent accelerates the curing of the phenolic resin in the binder-magnesia aggregate composition of the present invention. The ester function is provided by a lactone, a cyclic organic carbonate, a carboxylic acid ester, or a mixture thereof. Generally, low molecular weight lactones are ester functional hardeners such as, for example, beta or gamma-butyrolactone, gamma-valerolactone, caprolactone, beta-propiolactone, beta-isobutyrolactone, beta-isopentyl lactone, gamma-isopentyl lactone, and delta-pentyl lactone. Suitable for Examples of suitable cyclic organic carbonates include, but are not limited to, propylene carbonate, ethylene carbonate, 1,2-pentanediol carbonate and 1,3-pentanediol carbonate.

Carboxylic acid esters that can be used in the present invention include phenolic esters and aliphatic esters. The aliphatic ester preferably has a short or medium chain length, for example, a mono- or polyvalent saturated or unsaturated alcohol having 1 to 4 carbon atoms, and a short or medium chain length, for example, a chain length of about 1 to 10 carbon atoms. , Esters with saturated or unsaturated carboxylic acids, which are monocarboxylic or polycarboxylic acids. Preferred aliphatic esters are esters of alkyl, monohydric, dihydric or trihydric alcohols with alkyl, mono- or di-unsaturated acids which may be mono-, di- or tricarboxylic acids.

With respect to aromatic esters, such esters esterify the phenolic groups of aromatic compounds, such as mono- or polyvalent aromatic phenols, to produce formic or acetic acid esters of such aromatic compounds. Obtained by Further, the aromatic ester may have one or more phenolic hydroxyl groups and / or 1
Containing one or more esterified phenolic hydroxyl groups,
It may also be an esterified phenolic compound containing one or more esterified methylol groups arranged ortho or para to the phenolic hydroxyl group or the esterified phenolic hydroxyl group. Such phenolic esters are disclosed in Lemon et al., International Patent Application No. PCT / GB889 / 01526 filed December 21, 89.

The esterified phenol compound used is a mononuclear, dinuclear or polynuclear phenol in which at least one esterified methylol group is attached to a phenol hydroxyl group or an ortho or para aromatic ring carbon with respect to the esterified phenol hydroxyl group. It will be appreciated that can be The acid moieties of the phenolic ester can be the same as the aliphatic ester acid moieties.

Specific carboxylic acid esters include, but are not limited to, n-butyl formate; ethylene glycol diformate; methyl and ethyl lactate; hydroxyethyl acrylate; ethylene glycol diacetate; triacetin (glycerol triacetate); diethyl fumarate. Dimethyl maleate; dimethyl glutarate; dimethyl adipate; 2-acetyloxymethylphenol; 2-salicyloxymethylphenol; 2
-Acetyloxymethylphenol acetate; 2,6
-Diacetyloxymethyl p-cresol acetate;
2,4,6-triacetyloxymethylphenol;
2,4,6-Triacetyloxymethylphenol acetate; 2,6-diacetyloxymethylphenol acetate; 2,2 ', 6,6'-tetraacetyloxymethylbisphenol A; and 2,2', 6,6 '-
Includes tetraacetyloxymethylbisphenol A diacetate. Cyanoacetate derived from aliphatic alcohol having 1 to 5 carbon atoms; formate and acetate of benzyl alcohol; alpha, alpha'-dihydroxyxylenol;phenol; alkyl-substituted phenol;
Also suitable are dihydroxybenzene; bisphenol A; bisphenol F; and low molecular weight resoles. Sometimes
It is also advantageous to use a mixture of ester functional hardeners.

The ester functional curative is present in an amount sufficient to enhance the tensile and compressive strength of the ambient temperature curable composition. Such amounts of ester also enhance the cure rate of such compositions. The amount of ester used in the binder-aggregate composition of the present invention can vary over a wide range, such as about 5 to 25% by weight of the phenolic resin, preferably about 5 to 15% by weight of the resin. The exact amount depends on the particular ester curing agent used, the temperature of use and storage of the composition, and the desired result.

Retardant The retarder used in the present invention is hydrogen fluoride, hydrogen difluoride, phosphoric acid,
2- and 4-acetylphenol, 2- and 4-chlorophenol, tetraalkoxysilane in which each alkoxy group has 1 to 3 carbon atoms and a hydrolyzate of such silane,
Phosphoric acid, malic acid, oxalic acid, tartaric acid, aspartic acid (2
-Aminosuccinic acid), phosphonic acid and citric acid and salts thereof, eg at least 0.1% at 25 ° C.,
Preferably it has a water solubility of at least 2% by weight and the retarder compound comprises a salt such as is capable of providing an anion such as citrate to the composition. Some of the retarders are strong acids and care must be taken to maintain the binder-aggregate pH above about 4. Otherwise, acid decomposition of the phenolic resin will occur, prematurely curing the binder-aggregate composition.

Our Co-pending US Patent Application No. 562,2
No. 06 (filed on August 2, 1990) and No. 698,945
No. (filed May 13, 1991), which are hereby incorporated by reference herein for ionizable compounds, it is the anion () that determines whether these substances are retarders. For example, F ^- a). Thus, cations (eg, Na ⁺ , H ⁺ , K ⁺ ) do not change that anions are retarders, but compounds with low water solubility usually have a low retardation, and therefore a slight delay. Influence.
In the case of ionizable retarder compounds, such compounds impart a retarder anion to the composition. For this,
Some solubility in the composition, for example in binder-aggregates or water, is required. Thus, the fluoride in calcium fluoride is not effective as a retarder due to the low solubility of this compound in water. However, compounds that do not appear to ionize are also retarders. Such retarders include tetraalkoxysilane.

The advantage of using the ammonium or amine salt of the acid is that it is more soluble than the sodium or potassium salt. Partial neutralization with amines allows the use of high levels of acid in order to avoid excessive drops in pH which can lead to acid catalyzed polymerization. Premature settling of salts such as disodium citrate or disodium tartrate results in a heterogeneous mixture, affecting the retardation heterogeneously. Therefore, the bottom of the vessel of such a heterogeneous mixture will have a high concentration of retarder. Advantageously, the salt of the retarder is an amine salt. Specific examples of such amine salts are: N, N-dialkylethanolamines in which each alkyl group has 1 to 3 carbon atoms, preferably 1 to 2 carbon atoms; each alkyl group has 1 to 2 carbon atoms. o- and p-dialkylamine methylphenol; N, N-dimethylbenzylamine; N-alkylpiperidines in which each alkyl group has 1 to 2 carbon atoms; N-methyl and N-ethylmorpholine;
N, N-dimethylethanolamine; N, N-diethylethanolamine and the like. The amine is a tertiary amine. Primary and secondary amines can also be used with acid retarders provided that there is no undue destabilization of the resin relative to the use of tertiary amines. In any case, primary and secondary amines should be avoided if the organic ester is present as a retarder in the binder-aggregate composition. Specific examples of primary and secondary amines for forming salts of acid retarders include ethanolamine and its N-monomethyl and N-monoethyl derivatives; 1- and 2-aminopropanol; N-methylbenzylamine; Morpholine; piperidine and diethanolamine.

The retarder anion used in the present invention is aspartate, bifluoride, citrate, fluoride,
Malates, oxalates, tartrates, phosphates and phosphonates. It is preferred to combine the retarder anion with hydrogen as the cation and use it as a compound in acid form, for example as citric acid. Also preferred are cations of alkali metals, ammonium, and lower alkyl-substituted ammonium in which each alkyl group has 1 to 4 carbon atoms.

In the tetraalkoxysilane used as a retarder in the present invention, each alkoxy group has 1 to 3 carbon atoms. Partially prehydrolyzed tetraalkoxysilanes in which each alkoxy group has 1 to 3 carbon atoms can also be used and the degree of hydrolysis of such compounds can vary over a wide range, such as up to about 60%. The alkoxy groups of these silanes are the same or different.

Specific examples of specific retarder compounds include the following compounds: ammonium difluoride; ammonium fluoride; ammonium phosphate (monobasic); phosphoric acid; potassium fluoride; sodium fluoride; phosphoric acid Sodium (monobasic); Sodium phosphate (tribasic); Citric acid; Sodium citrate; Each alkyl group has 1 carbon atom
~ 3 N, N-dialkylethanolamine mono- and di-salts with citric acid; potassium tartrate; tartaric acid; malic acid; aspartic acid; and phosphoric acid. Specific examples of the organic phosphonic acid include diphosphonic acid, polyphosphonic acid,
These amine derivatives and their salts, such as Dequest 2000, phosphonic acid, Monsanto (M) such as [nitrilotris (methylene)] tris.
onsanto Co. This is the Dequest series sold by Kala.

Malates, tartrate and citrate such as malic acid, citric acid and their salts are
It has unusual properties as a retarder in that it exhibits early thixotropy. This is advantageous in that it provides high initial green strength (ambient temperature cure) with extended mix life.

The amount of the retarder used in the present invention is the binder-
An amount sufficient to reduce the rate of ambient temperature viscosity increase, gelation and curing of the aggregate material, such an amount being such that the activity of the particular retarder, the desired degree of retardation, room or ambient temperature, It can vary over a wide range depending on the amount of calcium oxide (generally as an impurity in the magnesia agglomerates) and whether an ester hardener is also used. Therefore, the amount of retarder is generally in the range of about 0.1-6% based on the weight of the phenolic resin. The preferred level of use of the various retarders is 0 for fluoride and bifluoride.
1-1.0%; 0.5-2.5% for phosphoric acid, silane and polycarboxylic acids; and 2-5% for substituted phenols. All of these usage levels are based on the weight of phenolic resin and are designated as "BOR".

Fillers, Agglomerates and Modifiers The compositions of the present invention may include fillers, modifiers and agglomerates, such as those commonly used in phenolic resins, other than magnesia agglomerates. This supplemental aggregate material is granular,
It is a granular material such as powder or flakes. Suitable supplemental agglomerate materials include, but are not limited to, magnesite, alumina, zirconia, silica, zircon sand, olivine sand, silicon carbide, silicon nitride, boron nitride, bauxite, quartz, chromite, corundum, and mixtures thereof. ..

The binder-aggregate composition obtained by incorporating the curable resin binder, the magnesia agglomerate and the retarder may further comprise some optional modifiers and additives. Such modifiers and additives include non-reactive solvents, silane, hexamethylenetetramine, clay, graphite, iron oxide, carbon pitch, silicon dioxide, metal powders such as aluminum, magnesium and silicon, air detraining agents ( air detrainini
ng agent), and mixtures thereof.

Uses The methods and compositions of the present invention can be used to produce refractory or ceramic products. They are particularly useful for the production of moldings such as adhesive dead-burned magnesia for the production of bricks and castable monolithic moldings. In the case of castable products, the binder-agglomerate mixture is generally of low viscosity and contains more resin than refractory materials such as bricks. Other ingredients may be added to the composition depending on the desired use. The amount of graphite in the binder-aggregate composition for refractory applications is generally in the range of about 5 to 35 wt% of the magnesia aggregate. Metal powders such as aluminum, magnesium and silicon are generally in the range of about 1-5% by weight of the magnesia agglomerate.

The mixing of the components of the binder-agglomerate composition of the present invention may be accomplished by any means known in the art, eg, Eilich mixer, Simpson (Simp).
It is carried out using an industrial mixer such as a son mixer, a Muller mixer or the like. The binder-agglomerate mixture resulting from the mixing step is shaped and pressed by methods known in the art to form the desired shape. The binder in the binder-magnesia agglomerate composition wets the agglomerate and allows the composition to be shaped, or allows the composition to be completely filled into the mold, for example by vibration.
For example, the binder-aggregate can be compression molded, isostatically pressed, transfer molded, extruded, or injection molded at any temperature and pressure. After molding, the molded body can be cured at ambient temperature, or the molded body can be further cured by heat curing before or after ambient temperature curing. Typical heat treatment is about ^{120 ℃ (248 0 F) ~205} ℃ (400 0 F)
Continuously increasing the temperature to thermoset the resin binder and evaporate the water and organic solvent. 800
Further heat treatment up to ℃ ~ 1000 ℃ further promotes carbonization of the resin binder.

For example, in the case of refractory material such as brick,
The binder-magnesia aggregate composition is compression molded into the desired shape and heat cured. Occasionally, from the manufacture of the composition, compression molding to the desired shape followed by, for example, about 230 ⁰ F
There is a delay before heat curing as at a temperature of (110 ° C). Such a delay can be a few minutes, but can last for a day or two. During such delay, the viscosity of the binder composition increases and the composition dries. Subsequent press forming and thermosetting of such binders into, for example, brick-like shaped bodies reduces the strength and / or yields products requiring additional pressure cycles to compress to the desired density. Occurs. Addition of a retarder slows the increase in viscosity to form a high ultimate tensile strength, compression molded, thermoset product.

For some refractory applications, an assembly formwork is required other than brick-like moldings. These "monolithic refractory materials" are cast by placing a viscous but flowable binder-agglomerate system into a mold and utilizing vibration to fill the mold. Once the binder-agglomerate system is room temperature cured, the mold can be removed and the shaped body can be heat cured to prepare it for use either before or after shipping the monolithic refractory material to its site of use. .. The retarder of the present invention allows for extended processing time for mold filling and composition compression molding. After room temperature curing, the monolithic can preferably be heat cured or carbonized at the point of use, for example as part of a furnace lining.

The following methods and examples are provided so that those skilled in the art may more fully understand the invention described herein. All parts and percentages in the examples, as well as elsewhere in this application, are by weight unless otherwise specified.

Resin Characterization Resin A. The resole resin was prepared by charging a formaldehyde to phenol molar ratio of 0.93 in the presence of an alkali catalyst. Resin A is 5100 at 25 ° C
It had a viscosity of cps, 3 wt% water, 22.7 wt% phenol content, 80 wt% solids and a pH of 8.0. It should be noted that although the formaldehyde to phenol ratio charged to the reactor is less than 1, the amount of formaldehyde that reacts with the phenol is substantially greater than 1 due to the large amount of unreacted phenol in the resin.

Resin B. This resol resin has a formaldehyde to phenol molar ratio of 1.
It was prepared by charging 20. Resin B is 25 ° C
Viscosity of 4100 cps at 7.9% moisture, 14.6
It had a% free phenol content, 79% solids, an approximate weight average molecular weight of 566 (excluding free phenol), and a pH of 7.9.

Resin C. This resol resin has a formaldehyde to phenol molar ratio of 1.
It was prepared by charging 25. Resin C has the following properties: viscosity at 25 ° C., 3,000 cps, 7.6% water, 13% phenol content, 78% solids, 406
Approximate weight average molecular weight of (excluding free phenol),
And had a pH of 7.8.

Resin D. This resol resin has a formaldehyde to phenol molar ratio of 1.
It was prepared by charging 25. Resin D has the following properties: viscosity of 3,000 cps at 25 ° C., moisture of 9.7%, free phenol content of 11%, solids content of 77%, 5
It had an approximate weight average molecular weight of 36 (excluding free phenol), and a pH of 7.9.

Production of Resin D. Phenol 3.621 kg
A solution of (38.55 mol) in 50% formalin 2.88
It was reacted with 5 kg (48.08 mol) and 38 g of 50% sodium hydroxide at 60-75 ° C. for 50 minutes. The reaction was then heated to 90-92 ° C for 40 minutes, then cooled to 60 ° C, at which time vacuum distillation was initiated at 26 inches of mercury. About 31% of the distillate was removed.
Residue at 75 ° C. for several hours, 25 ° C. at 3,000
Heated until a viscosity of 0 cps was reached. This residue was characterized as described in the Resin Characterization heading section above.

Production of Resin B. Resin B was prepared exactly as Resin D, using a formaldehyde / phenol molar ratio of 1.20, but proceeded to a slightly higher molecular weight and slightly higher viscosity at essentially the same solids.

Production of Resin E. This resole resin was prepared in the same manner as Resin B, using 80 mol% potassium hydroxide catalyst instead of sodium hydroxide catalyst. Resin E is 25
3,900 cps viscosity at ℃, 6.4% moisture, 14
% Free phenol, 79% solids, approximate weight average molecular weight of 370 (including free phenol), and 7.
It had a pH of 9.

Production of Resin F. The resole resin was prepared by charging a formaldehyde to phenol molar ratio of 0.95 in the presence of hexamethylenetetraamine as a catalyst. Resin F has a viscosity of 800 cps at 25 ° C., 10.9% water, 12.6% free phenol,
It had a solids content of 69%, an approximate weight average molecular weight of 278 (including free phenol), and a pH of 8.0.

Phenolic resin D / viscosity of high-purity magnesia
Method for Measuring the Effect of Resin, Solvent and Retarder on Degree This method is also referred to herein as "Method A". Resin 90g
Was thoroughly mixed with 72 g of high purity magnesia in powder form (passed through a 200 mesh US sieve series screen). The term "high purity" magnesia refers to 99 +% MgO content and 0.59% Ca (0.82 wt% as CaO).
And the dead burned magnesia having the grain size described in the above sentence. This mixture of resin and magnesia was then transferred to a 4 ounce bottle. Measure the freshly manufactured Brookfield viscosity at time zero, then close the bottle and contents at 25 ° C ± 1 ° C at about 32 revolutions /
Rotated in minutes. Viscosity is measured first, then 3, 6, 2
Measurements were taken at 4 hour intervals and possibly 48 hour intervals. The sample was immersed in a constant temperature bath one hour before the viscosity measurement. The sample was thoroughly stirred just before the viscosity measurement. This method is also referred to herein as "method A".

Phenolic resin / magnesia aggregate Mick
For qualitative flow
Method for measuring the effect of additives according to this method This method is also called "qualitative flow method". Glass vials (28 mm x 57 mm) were charged with 5.0 g of resin, additives and solvent, if present, and after formation of the solution, high purity magnesia, or, if specifically mentioned, "standard grade" magnesia 4.0 g. , Which was mixed thoroughly with a spatula for 1 minute, and then a 9-10 setting of American Scientific Products (Americ
S from an Scientific Products)
Mix for an additional 1 minute using a / P Vortex mixer. The term "standard grade" magnesia is about 9 MgO
It is used here to represent dead-burned magnesia containing 2% by weight and 2.48% by weight CaO (1.77% Ca) and having the same particle size as mentioned for the high purity magnesia of method A above. The relative viscosities of the mixes were determined by comparing two to five sets at the same time and laying them at right angles, ie on their sides, at room temperature (23-2
It was observed at various intervals when left at 5 ° C. All mixes were initially completely fluid, but generally 1
It became immobile and tack-free in ~ 7 days. The immobile mix is inspected with an applicator stick and ranges from initial stickiness to toffee-like stickiness to the next stickiness (ie the stick is pulled clean without resin sticking). The adhesiveness was evaluated. As the viscosity of the fluid mix increases, the mix becomes immobile. Further increase in viscosity is demonstrated by the sticking of the immobile mix to the applicator stick. A further increase in viscosity is indicated by a toffee-like stickiness, and a larger increase in viscosity is demonstrated by the applicator stick being pulled clean and free of resin. In addition, the relative increase in viscosity was recorded,
For example, 3>2> 1 means that the viscosity of mix 3 is greater than the viscosity of mix 2 (>), and the viscosity of mix 2 is greater than the viscosity of mix 1. The use of two or more symbols (>) means that the difference is large, ie the viscosity is increased compared to the use of one symbol (>). The mixture without additives is also called the "control".

Example 1 Phenolic resin / high purity magnesia
And Effect of Phenol This example was carried out according to Method A above with various resole resins with or without water or free phenol as indicated in the various mixes.

The results of this example are shown in Table 1. The entry of added water and added phenol in the table shows the case where the addition is performed to adjust the total amount of water or free phenol in the resin to the amount described in the table. Therefore, the amount of water or phenol in the table is the total amount of water in the sample to which the addition was made. As can be seen from the display 10 ^3, the viscosity readings 1000
Need to ride. Therefore, the viscosity reported value of 1.68 at 0 for Mix 1 is 1680c at 25 ° C.
ps. Resin A was used for Mixes 1, 2, and 3, while Resin B was used for Mixes 4 and 5. The column "without MgO" shows the viscosity of the mix without the addition of magnesia agglomerates.

As is clear from Table 1, the viscosity increasing rate increases as the amount of water increases, but the viscosity increasing rate decreases as the amount of free phenol increases.

[0084] Table 1 Phenol resin / high purity affect viscosity (25 ° C.) water and phenol on the viscosity of the magnesia Cpsx10 ³ mix water added phenol MgO 0 3 6 24 / addition / No Time Time Time Time total amount 1 8.1 --- 0.675 1.68 4.40 6.70 25.75 2 5.5 --- 1.55 3.76 6.10 7.60 19.75 3 --- --- 5.25 17.25 15.00 16.25 20.00 4 --- ー ー 2.25 7.50 18.00 27.25 110.00 5 --- ー ー 5.60 22.00 69.00 119.0> 4 Example 2 Effect of Additives on Viscosity of Resin B / High Purity Magnesia This example was carried out according to Method A above. The column labeled "No MgO" shows the viscosity of the mix with no magnesia added.

In this example, Mix 1 contained no additives. Mix 2 is 1.37% BOR malate
(Based on resin). Mix 3 contained 0.25% ammonium difluoride BOR and 0.38% water BOR. Mix 4 contained 1.4% BOR salicylate. Mix 5 is 1.4% salicylic acid BOR and 1.4
% Sodium salicylate BOR.

The results of this example are shown in Table 2. As is apparent from Table 2, the increase in viscosity of Mixes 2 and 3 was delayed compared to the control without any additive (Mix 1) and to Mixes 4 and 5 where the additive had no retarding effect. It was One of the unexpected results of this experiment is our co-pending US patent application No. 698,945 (May 13, 1991).
The salicylic acid (Mix 4) did not show a retarding effect, in contrast to the effect exhibited by light-burned magnesia in the same application. The same effect is shown if hard burned magnesia is used instead of dead burned magnesia.

Table 2 Effect of Additives on Viscosity of Resin B / High Purity Magnesia Mix Viscosity (25 ° C.) cps × 10 ³ MgO 0 3 6 24 48 72 No Time Time Time Time Time Time 1 4.40 17.75 56 92> 400-- --2 4.50 28.75 40 42 62> 400 --3 3.10 14.00 14.25 15.00 23 27.75 34.0 4 4.30 16.5 73.0 136> 400 ---- 5 5.15 22.75 81.00 142> 400 ---- Example 3 Resin C / high purity Acetic acid or g
Effect of Acid Additives This example was conducted to test the relative effect of acetic acid in Mix 2 and formic acid in Mix 3 as compared to the control without additives (Mix 1). The test was carried out according to the above qualitative flow method. Each mix contained 0.2 g of ethylene glycol and the amount of acetic acid or formic acid in each mix was 0.06 g (1.2% based on weight of resin).

As can be seen from Table 3, both acetic acid and formic acid accelerated curing, formic acid being the more effective curing agent than acetic acid.

Table 3 Effect of acetic acid or formic acid additives on qualitative flow of Resin C / high purity magnesia Elapsed time Order of viscosity increase of various mixes 0.5-1 3>2> 1 3 3> 2 >> 1 5 3 >> 2 >>>> 1 Mix 1 is still a perfect fluid 24 3> 2 >>>> 1 Mix 1 is still a fluid 34 3 is non-sticky, Mix 2 is still sticky 47 Mix 1 Is still fluid about 59 Mix 2 is non-sticky 96 Mix 1 is slightly mobile and sticky Example 4 Resin C / Glycol for qualitative flow of high purity magnesia
Effect of Acid, Lactic Acid and Malic Acid This example shows Mix 2 containing glycolic acid (hydroxyacetic acid) at a concentration of 1.1% BOR and 1.2% BO.
Relative to the viscosity of Mix 3 containing lactic acid (2-hydroxypropionic acid) at a concentration of R and Mix 4 containing malic acid (hydroxysuccinic acid) at a concentration of 1.2% BOR,
It was carried out according to the Qualitative Flow method in order to test the relative effect compared to Mix 1 without additives.

As can be seen from Table 4, glycolic acid and lactic acid promote viscosity increase, ie they act as accelerators. Malic acid has an apparent initial thixotropic effect, but actually delays the increase in viscosity.

Table 4 Effect of Glycolic Acid, Lactic Acid and Malic Acid on Qualitative Flow of Resin C / High Purity Magnesia Elapsed Time Order of viscosity increase of various mixes 1-6 4 >>2>3> 1 23 2,4>>3> 1 24 2> 3 >> 1 >>>> 4 Mix 2 is immobile but still sticky.

Remix all samples after 24 hours 72 Mix 4 is still flowable Performed according to the method of Example 4 but using hard burned magnesia or standard grade magnesia instead of high purity magnesia, malic acid It exhibits its retarding effect on the composition.

Example 5 Resin C / EDTA for qualitative flow of high purity magnesia-
Effect of Disodium Monohydrate, Malic Acid and Tartaric Acid This example shows that Mix 2 containing EDTA-Disodium-H ₂ O at 1.6% BOR; Mix 3 containing 1.4% BOR with malic acid 3; 1 Conducted to test the relative effect of Mix 4 with tartaric acid at 4% BOR as compared to Mix 1 without additives. This example was carried out according to the qualitative flow method described above. The results of this example are shown in Table 5.

As can be seen from Table 5, malic acid and tartaric acid are effective retarders, but EDTA-disodium-1
Hydrates are moderate retarders.

Table 5 Effect of EDTA-Disodium Monohydrate , Malic Acid and Tartaric Acid on Qualitative Flow of Resin C / High Purity Magnesia Elapsed Time Elapsed Sequence 1-3 1 2>3> 4 for viscosity increase of various mixes Equal to or slightly greater than.

Samples are remixed after 3 hours. 11-24 1> 2 >> 3 is equal to or slightly greater than 4.

Mix 2 is stopped.

28 1 >> 3,4 48 1 >> 3> 4, Mix 4 still very freely flowing 72 1 >>>> 3 >>>> 4, Mix 4 still very freely flowing 96 ( 4 days) Mix 1 approaches tack-free.

144 (6 days) Mix 4 still flows, but Mix 1 is non-sticky 8 days Mix 3 is non-sticky but Mix 4 is not non-sticky.

According to the method of this Example 5, when citric acid is used instead of tartaric acid, the hardening of the composition is delayed similarly to tartaric acid. The same effect occurs with hard burned magnesia or standard grade magnesia instead of high purity magnesia.

Example 6 Resin B / malic acid on qualitative flow of high purity magnesia
Bimalic acid mixed with 4'-hydroxyacetophenone
Effect This embodiment of things and malic acid in 1.2% BOR of Mix 1, the relative effect on Resin B of a mixture of Mix 2 containing 1.2% malic acid BOR and 4'-hydroxyacetophenone 4% BOR Was carried out for testing. This example was carried out according to the qualitative flow method described above.

As can be seen from Table 6, 4'-hydroxyacetophenone initially increases the mix viscosity, but ultimately delays it. Similar results occur when 2'-hydroxyacetophenone is used in place of 4'-hydroxyacetophenone in this example.

[0103] Table 6 Resin B / High purity and malic acid and malic acid on Qualitative flow magnesia 4'hydroxyaldehyde order effects elapsed time increase in viscosity of the various mix of a mixture of acetophenone 1/6 to 2.5 2 > 1 Remix after 2.5 hours 4 2 >> 1 Mix 2 moves very slowly 6-20 2 >> 1 Remix after 20 hours 20 2 is the same as 1 6 2 is equal to 1 or Slightly greater than 1 48-96 1 >> 24 After 4 days, Mix 2 still flowed fairly well.

144 (6 days) Mix 1 is non-tacky, but Mix 2 is not non-tacky.

Example 7 Resin D / Adipic Acid for High Purity Magnesia Flow,
Effect of Succinic Acid and 4-Nitrophenol This example shows that Mix 2 with adipic acid at a concentration of 1.6% BOR; Mix 3 with succinic acid at a concentration of 1.6% BOR; and 4% BOR concentration. Mix 4 with 4-nitrophenol, mix 1 without additives
Was performed to test the relative effect compared to.

The test results are listed in Table 7. As can be seen from Table 7, adipic acid, succinic acid and 4-nitrophenol act as viscosity enhancers. The same result can be obtained by using hard burned magnesia instead of dead burned magnesia in this embodiment.

Table 7 Effect of adipic acid, succinic acid and 4-nitrophenol on the flow of Resin D / high purity magnesia Elapsed time Sequence of increasing viscosity of various mixes 1 2>3> 4 1 or greater than 1 Somewhat large 4 2>3>4> 1 6 Mix 2 moves very slowly 23 Mixes 2 and 3 show no flow, are non-sticky, mix 1 shows a little flow, mix 4 shows a flow 47 but not tack free 47 Both Mix 1 and 4 are tack free but Mix 4 is slightly stiffer Example 8 Resin D / Glutamine for high purity magnesia flow
Acid, malic acid and malic acid with 2-chlorophenol
Effect of Mixture This example was carried out with Resin D according to the Qualitative Flow method described above. Glutamic acid at a concentration of 1.6% BOR was found to show equivalent results to the control after 0.5 and 23 hours.

Mix containing 1.2% BOR concentration of malic acid and 4% BOR concentration of 2-chlorophenol.
The mix containing 2% BOR concentration of malic acid was compared to each other. The addition of 2-chlorophenol to malic acid extended the mix life at 5 minute intervals over 48 hours compared to malic acid alone. After 48 hours, the malic acid mix is tack free (stick is clean) but the mix containing chlorophenol and malic acid is not tack free. The same result is obtained by using ammonium malate instead of malic acid in this example.

From Example 8 it can be concluded that glutamic acid has little or no effect on viscosity, whereas 2-chlorophenol delays the increase in viscosity of the mix.

Example 9 Malic acid, magnesium hydrogen malate, malic acid and phosphorus
Mixture with monoammonium gorate, malic acid and 4'-hydride
Mixture with loxyacetophenone, and malic acid and 2 '
-Resin D / high purity of mixture with hydroxyacetophenone
Effect of magnesia on flow This example was carried out according to the above qualitative flow method in two parts. Part 1 has 1.4% BOR compared to Mix 2 containing magnesium hydrogen malate at a 1.9% BOR concentration
A test was conducted to evaluate the relative viscosity change with Mix 1 containing malic acid at a concentration. In the second part of this example, Mix 3 containing malic acid at 1.4% BOR concentration as a mixture with 2.4% BOR concentration of monoammonium malate; with 4'-hydroxyacetophenone at 4% BOR concentration. Compare the viscosity change of Mix 4 containing malic acid at 1.4% BOR concentration as a mixture; and Mix 5 containing malic acid at 1.4% BOR concentration as a mixture with 4% BOR concentration of 2'-hydroxyacetophenone. Therefore, a test was conducted. The results of these tests are shown in Table 9. As can be seen from Table 9, magnesium hydrogen malate initially increases viscosity compared to malic acid, but 1-2
Decrease viscosity after days. 2'-Hydroxyacetophenone is a less effective retarder than its 4'-isomer, but both are used in combination with malic acid.

Table 9 Resins of malic acid, magnesium hydrogen malate, a mixture of malic acid and monoammonium malate, a mixture of malic acid and 4'-hydroxyacetophenone, and a mixture of malic acid and 2'-hydroxyacetophenone. D / high purity magnesia flow order effects elapsed time mix viscosity increase of relative movement (part 1) 1-3 2 >> 1 3 hours after remixing 5 2> 1 8 mix 2 is equal to or mix mix 1 Slightly greater than 1 10 Mix 1 is equal to or slightly greater than Mix 2 11-48 1 >> 2 72 Both mixes are tack free Elapsed time Sequence of increasing viscosity of various mixes (second Part) 1/3 to 4 3>4> 5 10 3,4> 5 22 3>5> 4 22 hours Re-mixing before inspection 46 3>5> 4 58 Mix 3 Is non-tacky 70 Mix 5 is non-tacky, Mix 4 is non-tacky Example 10 Salicylaldehyde, Salicylamide and 2-Nitroph
For qualitative flow of enol resin D / high-purity magnesia
Impact This example shows mix 2 with salicylaldehyde at 4.4 BOR concentration; mix 3 with salicylamide at 4.4 BOR concentration; 2-nitro at 4.4 BOR concentration to show viscosity change according to the above qualitative flow method. Performed using Mix 4 with phenol; and Mix 1 as a control with no additives. The results of these tests are shown in Table 1.
It shows in 0. As can be seen from Table 10, after one day salicylaldehyde and 2-nitrophenol increase the mix viscosity compared to the control and salicylamide.

[0112] Table 10 salicylaldehyde, salicylamide, and 2-nitrophenol resin D / high purity order of impact elapsed time increase in viscosity of the various mix for qualitative flow magnesia 2.5-7 2>4> 1,3 23 2,4> 1,3 Mixes 2 and 4 are essentially immobile, but not tack free.

48 All mixes are immobile and tack free.

Example 11 Malic acid and malic acid and N, N-dimethyl ethanol
Resin B in a mixture with min / qualitative flow of high-purity magnesia
Impact on In this example, the resin is Resin B and 2.8% BOR
Viscosity comparison by qualitative flow method for a concentration of malic acid (mix 1) and a mixture of 2.8% BOR concentration of malic acid and 1% BOR concentration of N, N-dimethylethanolamine (DMEA) (mix 2) Was carried out.

The results of this example are shown in Table 11, Table 10.
As can be seen, increasing malic acid concentration in the presence of DMEA is very effective in extending flow and mix life.

Table 11 Effect of malic acid and a mixture of malic acid and N, N-dimethylethanolamine on the qualitative flow of Resin B / high purity magnesia Elapsed time Sequence 1 of increasing viscosity of various mixes Mix 2 to Mix 1 Equal to or slightly greater than Mix 1 2 2> 1 Remix after 2 hours 4-7 2 >>>> Remix after 6 hours 24 2 >> 1 7 No apparent change from 72 hours 72 2 >> 1 24 hours Mix viscosity rises slightly after 72 hours, re-mixing at this time 1> 2 95 Mix 1 is non-sticky, but Mix 2 still shows flow 7 days Mix 2 is not yet non-sticky.

Example 12 Curing Delay with Ammonium Fluoride Ingredients: Resin M at a concentration of 36 g / 300 g of a mixture of three sands as described below; gamma-butyrolactone (25% BOR); about 18% dead burned magnesia coagulation. A raw batch composition was prepared by thoroughly mixing the aggregate BOR; water, 8.3% BOR; and 1% BOR of 3-glycidoxypropyltrimethoxysilane. Resin M is a phenol-formaldehyde resol resin produced by reacting formaldehyde and phenol in a molar ratio of 1.25 using sodium hydroxide as a catalyst. This resin intermediate is then followed by acetic acid, ethanol, methanol and N, N
-Mixed with dimethylformamide (DMF), resin M
To form. Resin M has a Gardner-Holt viscosity of 2,560 centistokes at 25 ° C or about 3,000 cps at 25 ° C; 68% solids; 7% free phenol; 10% lower alkyl alcohol; 12% moisture; 4%.
DMF; having a pH of 5.9 and a weight average molecular weight of 4,000. The sand mixture is 198 g of coarse sand, medium grain (medium)
Grain) sand 72 g; and 30 g of fine sand. Deadburned magnesia aggregates contained 98.1% MgO on a combustible basis and had a bulk specific gravity of 3.28, 95% of which passed a 50 US sieve series screen. The raw batch composition was 105 psi without retarder.
24 hour compressive strength. With the addition of 2% BOR of ammonium fluoride, the composition after 5 days at room temperature
It was still soft. Similar results are obtained using propylene carbonate or triacetin instead of butyrolactone according to the method of this example. Using hard-burned magnesia instead of dead-burned magnesia in this embodiment also causes a delay.

Example 13 In a resole / novolak blend with high purity magnesia
Effect of retarder against novolak A solution (solid content 65%, furfuryl alcohol 25% and ethanol 10%, molecular weight about 600,
About 2170 cps, having a viscosity of 25 ° C) 1: 1
Resin D was mixed in a weight ratio of about 2520 cps, 25
A viscosity of ° C was obtained. This composition was tested as Mix 1, without additives, and as a 33% aqueous solution 0.33% BOR
Mix 2 of dispersed ammonium difluoride
Tested as. These two mixes were tested by the qualitative flow method. The results are shown below.

Elapsed time Order of viscosity increase for different mixes 1-3 Mix 1 is equal to or slightly greater than Mix 2 6-10 1> 2 14-23 1 >> 2 As can be seen from the above results. Ammonium difluoride is a very good mix life extender for blends of resole and novolak.

Example 14 Using novolak alone with high-purity magnesia
Effect of Retardant on Qualitative Flow This example shows the effect of retarder on qualitative flow when using only Novolac A with high purity magnesia. Example 13 above having a viscosity of about 2170 cps, 25 ° C.
Novolak A solution of Bifluoride retarder (0.33%
Tested according to the qualitative flow method with or without BOR). After 24 and 50 hours both the samples with and without the retarder were very flowable. The same results were observed after 5 and 7 days. In this example, the retarder had no effect on the sample during the period of interest.

Example 15 Novola as Phenolic Resin with Standard Grade Magnesia
Effect of Retardant on Qualitative Flow Using Kock Only This example demonstrates the effect of retarder on the use of Novolac B with standard grade deadburned magnesia but no resol resin. Phenol-formaldehyde novolac B resin is dissolved in ethylene glycol as a 60% solids solution to give about 3.5% water, about 3,000
With a viscosity of about 5,700 cps. The method used in this example is the qualitative flow method. Standard grade magnesia is only 0.82% CaO in high purity magnesia.
In the place of 2.5% CaO. Mix 1 was a control with 0.6% BOR moisture. Mix 2
Contained 0.33% ammonium difluoride, dispersed as a 33% aqueous solution.

Elapsed Time Sequence of viscosity increase 1-8 for various mixes Mix 1 is equal to or slightly greater than Mix 2 and both are very fluid.

27 Mix 1 is equal to or slightly larger than Mix 2 and both mixes are quite fluid.

31 Mix 1 is equal to or slightly greater than Mix 2 36-72 1> 2 Both are still mobile 72 1> 2 Both are still mobile As can be seen from the table above, only 0 The use of standard grade magnesia containing 2.5% CaO in place of high purity magnesia containing 0.82% CaO was very effective in retarding resin cure during the period of interest. Similar results are obtained with hard-burned magnesia containing about 2.5% CaO instead of standard grade magnesia.

Example 16 Resin D / High-purity magnesia
Effect of Nmmonium This example illustrates the effect of retarder on the use of Resin D and standard grade magnesia. Mix 1 in the table below
Is control + water 0.6% BOR, mix 2 is 33%
It contained 0.33% ammonium difluoride BOR dispersed as an aqueous solution.

Elapsed time Order of viscosity increase of various mixes 1/3 Mix 1 is equal to or slightly greater than Mix 2 1-2 1> 2 3-6 1 >> 26 After 6 hours, Mix 1 Moves very slowly 20 1 >>>> 2 Mix 1 is Tuffy-like 47 1 >>>> 2 Mix 1 is tack free. Mix 2 is still quite mobile.

As can be seen from the results of Example 16, the bifluoride retardant is also very effective against high calcium magnesia aggregates.

Example 17 Resin D / Silane and polyphosphonate for high purity magnesia
Effect of Acid This example was carried out as described in the Qualitative Flow Method section.
Mix 1 was a control with 2% water as diluent. Mix 2 has 2% BOR water as diluent and 2
% BOR of tetraethyl orthosilicate (tetraethoxysilane) was included. Mix 3 contained 2% BOR of water and 2% BOR of aminotri (methylenephosphonic acid). The test of this example was carried out according to the qualitative flow method and the results are shown below.

Elapsed time Order of viscosity increase of different mixes 1 1> 3,3 is equal to 2 or slightly greater than 2 3 1 >> 3 2 is equal to or slightly greater than 2 7 1 >>3> 2 27 1> 3 >>>> 2 Mix 1 is thick, tuffy-like, mix 2 is still almost liquid 36 1> 3 >>>> 2 Mix 2 is still liquid 39 Mix 1 is tack free Not 48 Mix 1 is non-sticky, but Mix 2 is still flowable 72 Mix 3 is non-sticky, but Mix 2 is still flowable.

As is apparent from the results of Example 17, tetraethoxysilane is an effective retarder, while polyphosphonic acid is a less effective retarder than silane.

Example 18 Resin D / Ester and Slow for High Viscosity Magnesia Viscosity
Effect with Spreading Agent In this example, two sets of tests were performed. The first series of tests were conducted according to Method A above and the results of these tests are shown in Part A below. The second series of tests were conducted according to the qualitative flow method and the results of these tests are shown in Part B below. In both Part A and Part B, Mix 1 contains no additive but instead 2-methoxyethyl ether (inert solvent) 10% BOR and 0.
The control was with 5% water BOR; Mix 2 was 1
Gamma-butyrolactone with 0% BOR concentration and 0.5%
Contains BOD concentration of water; Mix 3 is 10% BO
R concentration of gamma-butyrolactone and water 0.75% BO
It contained ammonium difluoride 0.25% BOR added as a 33% solution in D. Part 1 table 1st
In the column, the heading "without MgO" means that the viscosity measurements were taken before the addition of high purity magnesia, ie the composition was "neat".

[0132] Part A mix viscosity ^{(25 0), cps x 10} 3 MgO None 0:00 6:00 24 1 1.900 4.70 22.50 158.00 2 1.250 4.60> 400ｰｰｰ3 1. 000 4.70 11.75> 400 As can be seen from Part A above, bifluoride has a strong retarding effect of at least 6 hours (Mix 3 vs. Mix 2) and replacement of the ester with an inert solvent greatly increases mix life. Extend (Mix 1 vs. Mix 2).

Part B Mix 1 hour aged mix thoroughly, transfer approximately 11 g of each mix to a vial and observe viscosity change over time.

Elapsed time Mix viscosity increase order 0 Mix 2 is equal to 1> 3 or slightly greater than 1> 3 1 2>3> 1 2 2 >>>3> 1 3 2 >>3> 1 Mix 3 is still very fluid 6 2 >>>>1> 3 Mix 3 is still very fluid 22 2,3 >> 1 Mix 2 is near tack free. Mix 3 is very sticky. Mix 1 is moderately mobile.

30 Mix 2 is tack free.

44 Mix 3 is tack free. Mix 1 moves very slowly.

69 Mix 1 is immobile and sticky.

95 Mix 1 is not tack free.

As can be seen from Part B of this example,
The conclusions of Part A are substantiated. Bifluoride has a strong retarding effect, and replacement of the ester with an inert solvent greatly extends the mix life. This also demonstrates the validity of correlating the qualitative flow method with the method of obtaining Brookfield viscosity as in Method A.

Method of Making Fire Resistant Tensile Specimens Dead burned magnesia with 99 +% MgO content and 14/48 sheave size 1360 g; 99 +%
240 g of dead-burned magnesia having a MgO content of -200 mesh sieve size; and 2.0 kg of agglomerate mix containing 400 g of crystalline graphite were placed in a plastic bag in a 130 ⁰ F (54 ° C) oven,
Stored overnight. The hot agglomerates were mixed with 5 quart 3-speed Hobart mixer.
Bart mixer) and 83.3 g of resin [4.2% based on agglomerates, preheated to 90 ⁰ F (32 ° C)] were added. The complete mix was obtained by mixing at low speed for 1 minute, medium speed for 5 minutes and high speed for 3 minutes. The final mix temperature was about 160 ⁰ F (41 ℃). The die was charged with 150 g of mix and compressed under 15 tons pressure for 1 minute to give a length of 3 inches and a thickness of 1
An inch, 1 inch neck dogbone specimen was manufactured. The unused mix is 90 for later use.
⁰ F Put in oven. Tensile strength (psi) was measured with a Universal Sands tester.

Example 19 Effect of retarder on mix life / tensile strength of Resin D
Fruit was above to produce a refractory tensile specimens according to the production method of the refractory tensile specimens, resin used was Resin D. Mix 1 was the control and contained no retarder. Mix 2 contained 1.4% malic acid BOD. Tensile strength was measured at various times as shown in the table.

Tensile Strength, PSI (Average of 2 or 3) Mix 0: 4: 24: 48: 72: 11 11 8 16 21 32 32 2 6 5 17 30 61 Mix 1 was gradually dried over time. Mix 2 remained moist than Mix 1. As is apparent from the above table, retarders reduce initial strength (0-4
H) equals to control after 1 day and shows significantly higher intensity after 2-3 days.

Example 20 Resin B / High Purity Magnesia Qualitative Flow Study This example was conducted according to the Qualitative Flow Method. Results were recorded by comparing samples with various additives as described below with controls without additives. The test period lasted for 5 days. 1.0% BOR trimellitic acid (1,
The 2,4-benzenetricarboxylic acid) additive acted as a moderately effective accelerator. The 1.5% BOR concentration of sulfanilic acid (4-aminobenzenesulfonic acid) additive acted as a mild accelerator and the 1.5% BOR concentration of aspartic acid additive acted as a mild retarder.

Example 21 Resin D / High-purity magnesia
Effects This example was carried out according to a qualitative flow for Resin D as phenolic resin and high purity magnesia as agglomerate. Mix 1 is a control with no additives,
Compared to Mix 2 containing citric acid dispensed as a 55% aqueous solution. The results are shown below.

Elapsed time Order of viscosity increase of different mixes 0.5 2 >> 1 3.5-5 6 2> 1 Remix after 6 hours 6 * 1> 2 Therefore, citric acid shows an early thixotrope 11- 19 1 >> 2 22 1 >>>> 2 Mix 1 is immobile, Mix 2 is still almost liquid 45 Mix 1 is not sticky, but Mix 2 is still mobile 70 Mix 1 is barely immobile Sticky but mix 2 moves slowly 94 Mix 2 is almost non-sticky * As can be seen from this Example 21, citric acid gives an early thixotrope and is an effective retarder.

Example 22 Resole / Retarder Mix Compatibility Study The purpose of this example was to investigate the compatibility of different retarders in different resole resins. The method used in this example was to simply add the retarder to the resin in the glass vial at the concentration in parentheses (BOR) after the additive name in Table 22. In one of the mixes, the amine salt former was added to the acid retarder at the concentration BOR listed in the table. The materials in the glass vials were mixed vigorously and observed after the designated period. The results are shown in Table 22 below.

Table 22 Observation of resin retarder (% BOR) B Ammonium difluoride (0.2%) Immediately emulsified. Solids settled very slowly after a few days.

B Malic acid (2%) and salicyl (precipitation after 1 day.

0.8%) B Ethyl orthosilicate (2%) Turbid within 1 day. Over the course of a few days (tetraethoxysilane) it becomes increasingly opaque B Malic acid (2%) and choline base (precipitates within 1 day 0.9%) B Oxalic acid (0.8%) 1 day less Precipitation formation within B B Citric acid (1.1%) Turbid after 1 to 22 days but no precipitation formed D Malic acid (2.5%) and N, N-12 days after which crystals were apparent.

Dimethylethanolamine (1.3%) D Malic acid (1.4%) Significant crystals observed after 6 days.

E Ammonium difluoride (0.28%) Clear after 25 days E Citric acid (1.1%) Clear after 25 days E Malic acid (1.1%) Appearance of granular turbidity after 4 days E Tartaric acid ( 1.1%) Turbid after several hours. Cloudy after about 14 hours, no obvious change by 3 days, some precipitation present after 2 weeks.

F Ammonium difluoride (0.28%) Clear after 25 days F Tartaric acid (1.1%) Clear after 25 days The results of this example show that potassium hydroxide catalyzes a resol resin (resin E ) And an amine-catalyzed resol resin (resin F) have improved compatibility with retarders as compared to sodium hydroxide-catalyzed resol resin (resin B). Show.

Example 23 Ionization constants (p of acid and phenol used in Examples )
K _a) This example shows the type of activity of the various additives in the S column, "A" indicates that the additive is a promoter,
"R" indicates that the additive is a retarder and "N" indicates that the additive is neutral. Table also shows the pK _a of the additive, pK ₁ is a pK _a of monoacid. The pK _a value is Jay. A. J. A. Dean, Handbook of Organic Chemistry (Handbook of Organics)
Chemistry, McGraw-Hill Publishing House (McG)
raw-Hill Publishing Co. )
(NY, 1987).

S additive (acid) pK ₁ (pK _a ) pK ₂ pK A acetic acid 4.76 A adipic acid 4.42 5.41 R aspartic acid 3.87 10.00 R 2-chlorophenol 8.55 A Formic acid 3.75 N glutamic acid 4.31 9.76 A glycolic acid 3.83 R citric acid 3.13 4.76 6.40 R hydrogen fluoride 3.17 R 2'-hydroxyacetophenone 9.90 R 4'- Hydroxyacetophenone 8.05 A Lactic acid 3.86 R Malic acid 3.46 5.10 A 2-Nitrophenol 7.22 A 4-Nitrophenol 7.15 R Oxalic acid 1.27 4.27 R Phosphoric acid 2.157 .20 12.38 N salicylic acid 2.98 A salicylaldehyde 8.34 N salicylamide 8.36 R silicic acid 9.77 11.80 A Curic acid 4.21 5.64 A Sulfanilic acid 3.23 R Tartaric acid 3.04 4.37 A Trimellitic acid 2.52 3.84 5.20 * Partial hydrolysis product of tetraalkoxysilane Ionization constant and resin / Example 2 shows that there is no clear correlation with the retarder / accelerator activity of the MgO mix.
It is clear from 3.

Example 24 Effect of Additives on the Flow of Resin B / High Purity Magnesia This example was conducted according to the Qualitative Flow Method. In this example, Mix 1 is a control with no additive, Mix 2 contains 1.4% BOR of phenolsulfonic acid as an additive, Mix 3 is nitric acid as an additive of 1.1% BOR. Contains lithium, mix 4 is 1.4%
Ammonium sulfamate was included as a BOR concentration additive. All mixes contained 1.4% added water BOR. The results of this example are shown below.

Elapsed time Order of viscosity increase for different mixes 0.5 4>2>3> 1, where 4 >> 1 1 4 >> 2 is equal to 3> 1 or slightly more than 3> 1. Large 2 4 >> 2 is equal to 3 >> 1 or slightly larger than 3 >> 1 Mix 1 is immobile, but Mix 1 is mostly liquid 3 4> 2,3 >> 1 Mix 4 is non-sticky 9 3> 2 >>>> 1 Mix 1 is still moderately fluid 14 Mix 3 is near non-sticky, but Mix 2 is not non-sticky 21 Mix 2 and 3 Non-tacky 31 Mix 1 still flows 48-72 Mix 1 is sticky 96 Mix 1 is non-sticky As evidenced by Example 24 ammonium sulfamate is a strong accelerator. Yes, phenolsulfonic acid and nitric acid Umm is a good accelerator. In an experimental run similar to the above, 2% BOR concentration of acetylacetone (2,4-pentanedione) showed mild promoter activity, i.e. lower than that in Example 24 above.

Example 25 Effect of Additives on Resin E / High Purity Magnesia Flow This example was carried out according to the Qualitative Flow method. In this example, Mix 1 was the control and contained no additives. Mix 2 contained 2% BOR concentration of P-toluenesulfonic acid as an additive. Mix 3 contained as additives 1.5% BOR concentration of citric acid and 1% BOR concentration of N, N-dimethylethanolamine (DMEA). All mixes contained an additional 1.4% BOR water. The results of this example are shown below.

Elapsed time Sequence of viscosity increase for different mixes 0.66 3>2> 1 1-5 3>2> 1, mix 3 hardly migrates after 3-5 hours 6 remix after 6 hours, then 2 >>3> 1 14 3 is equal to 2 >> 1 or slightly greater than 2 >> 1 24 2,3 >> 1 Mix 1 flows fairly easily. Remix 1 and 3, 1 and 3 can be easily remixed, but Mix 2 is tacky and cannot be mixed. After remixing, 2 is equal to 1 >> 3 or slightly greater than 1 >> 3, Mix 3 shows good flow.

26-332 is equal to 1 >> 3 or slightly larger than 1 >> 3. Mix 3 shows good flowability, while Mix 2 is not tack free.

39 2 >> 1 >> 3 Mix 2 is only slightly tack free.

72 Mix 1 is still sticky and flows very slowly. Mix 3 is still moderately liquid, but shows good liquidity after remixing.

127 Mix 1 is not tack free and Mix 3 shows moderately good flowability.

144 Mix 1 is tack free and Mix 3 shows moderately good fluidity.

288 Mix 3 flows before and after remixing.

336 Mix 3 still flows.

The resin solution containing retarder used to make Mix 3 was clear and homogeneous for at least 13 days.

As can be seen from the results of Example 25, p-
Toluenesulfonic acid is a promoter, but citric acid / DM
EA exhibits an early thixotrope, but it is a strong retarder.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical display location C08K 5/54 C08L 61/06 LMR 8215-4J

Claims (55)

[Claims] 1. A method of retarding ambient temperature cure of a mixture of phenolic resin and magnesia agglomerates, comprising the following elements: A. Magnesia aggregates; B. , Novolac, a resole having a pH of about 4.5-9.5 and a viscosity of about 100-10,000 cps at 25 ° C., and mixtures thereof, wherein the agglomerates are formed during thermosetting of the resin. Curable phenolic resin solution in an amount sufficient to bind; C.I. The following elements: a. A compound that provides aspartate, bifluoride, citrate, fluoride, malate, tartrate and phosphonate anions to the mixture; and b. Tetraalkoxysilane in which each alkoxy group has 1 to 3 carbons, Partially hydrolyzed tetraalkoxysilane in which each alkoxy group has 1 to 3 carbons, 2-chlorophenol, 4-chlorophenol, 2'-hydroxyacetophenone and 4 '-Hydroxyacetophenone; as well as a compound selected from the group consisting of mixtures of these retarders, the method comprising admixing a retarder compound in an amount sufficient to delay ambient temperature cure of said mixture. 2. The aggregate is deadburned.
2. The method according to claim 1, which is rned) magnesia. 3. The aggregate is hard-burned (hardbu).
2. The method according to claim 1, which is rned) magnesia. 4. The method of claim 1 wherein the resin is a resole resin having a pH of 5 to 8.5 and a viscosity at 25 ° C. of about 250 to 5,000 cps. 5. The anion is bifluoride.
The method described. 6. The method according to claim 1, wherein the anion is citrate. 7. The method of claim 1, wherein the anion is fluoride. 8. The method of claim 1, wherein the anion is malate. 9. The anion is tartrate.
The method described. 10. The compound providing an anion is an acid,
The method of claim 1, wherein the phenolic resin is a condensation product of phenol and formaldehyde. 11. A compound wherein each alkoxy group has 1 carbon atom
The method of claim 1, wherein the tetraalkoxysilane is 3 to 3. 12. The compound has an alkoxy group having 1 to 1 carbon atoms.
The method of claim 1, wherein the partially hydrolyzed tetraalkoxysilane is 3. 13. The method of claim 1 wherein the phenolic resin is a solution of novolac in an organic solvent and the agglomerates contain about 1.5% to 4% calcium oxide. 14. The method of claim 1 wherein the phenolic resin is a mixture containing about 1-4 parts by weight of resole per part by weight of novolak. 15. The mixture comprises about 5 to 35% by weight of graphite based on the weight of the agglomerates, 1 to the weight of the agglomerates.
The method of claim 1 comprising 5% by weight of a metal powder selected from the group consisting of aluminum, magnesium and silicon, and an additive selected from the group consisting of mixtures of said additives. 16. An ester functional curing agent wherein the mixture is selected from the group consisting of lactones, carboxylic esters, cyclic organic carbonates and mixtures thereof.
functional hardening agen
4. The method of claim 3 including t), wherein the amount of curing agent is sufficient to enhance the tensile and compressive strengths of the cured mixture at ambient temperature. 17. A method of retarding ambient temperature cure of a mixture of phenolic resole resin and magnesia agglomerates, comprising the following elements: A. Magnesia aggregates; B. PH of 4.5-9.5, about 100-at 25 ° C
A curable phenolic resole resin solution having a viscosity of 10,000 cps and a water content of about 3 to 15% by weight,
A curable phenolic resole resin solution in which the amount of the resole is sufficient to bind magnesia when the resin is cured; C. The following elements: a. A compound that provides aspartate, bifluoride, citrate, fluoride, malate, tartrate and phosphonate anions to the mixture; and b. Tetraalkoxysilane in which each alkoxy group has 1 to 3 carbons, Partially hydrolyzed tetraalkoxysilane in which each alkoxy group has 1 to 3 carbons, 2-chlorophenol, 4-chlorophenol, 2'-hydroxyacetophenone and 4 '-Hydroxyacetophenone; as well as a compound selected from the group consisting of mixtures of these retarders, the method comprising admixing a retarder compound in an amount sufficient to delay ambient temperature cure of said mixture. 18. The method of claim 17, wherein the anion is bifluoride. 19. The anion is citrate.
7. The method according to 7. 20. The anion is fluoride.
7. The method according to 7. 21. The anion is malate.
The method described. 22. The method of claim 17, wherein the anion is tartrate. 23. The method of claim 17, wherein the retarder is an acid. 24. In the compound, each alkoxy group has 1 carbon atom.
18. The method of claim 17, wherein the tetraalkoxysilane is 3 to 3. 25. In the compound, each alkoxy group has 1 carbon atom.
18. The method of claim 17, which is a partially hydrolyzed tetraalkoxysilane that is -3. 26. The method of claim 17, wherein the magnesia is dead burned magnesia. 27. The method of claim 17, wherein the resole resin comprises less than 1% by weight sodium or potassium. 28. The resin is about 250-5 at 25 ° C.
It has a viscosity of 000 cps and a solids content of about 50-90% by weight, the mixture contains about 3-12% by weight of water, the magnesia contains less than 3% by weight of calcium oxide, and the phenolic resole comprises phenol and formaldehyde. The method according to claim 17, which is a condensation product. 29. The method of claim 28, wherein the resin comprises less than 0.5% by weight sodium or potassium. 30. The mixture comprises an ester functional curing agent in an amount sufficient to enhance the tensile and compressive strength of the composition after curing at ambient temperature, wherein the ester is a lactone.
29. The method of claim 28 selected from the group consisting of carboxylic acid esters, cyclic organic carbonates and mixtures thereof. 31. The method according to claim 30, wherein the ester is a lactone.
The method described. 32. The following elements: A. Magnesia aggregates; B. A curable phenolic resin solution selected from novolac, a pH of about 4.5 to 9.5, a resole having a viscosity of about 100 to 10,000 cps at 25 ° C., and mixtures thereof, wherein the amount of resin is magnesia. About 3
~ 15 wt% curable phenolic resin solution; C.I. The following elements: a. A compound that provides the composition with aspartate, bifluoride, citrate, fluoride, malate, tartrate and phosphonate anions; and b. Tetraalkoxysilane in which each alkoxy group has 1 to 3 carbons, Partially hydrolyzed tetraalkoxysilane in which each alkoxy group has 1 to 3 carbons, 2-chlorophenol, 4-chlorophenol, 2'-hydroxyacetophenone and 4 A binder-coagulant containing a wet mixture of retarder compounds in an amount sufficient to retard ambient temperature cure of the mixture, which is a compound selected from the group consisting of'-hydroxyacetophenone; and mixtures of these retarders. Aggregate composition. 33. The phenolic resin is a resol having a pH of 5 to 8.5 and a viscosity of 250 to 5,000 cps at 25 ° C., and the resol contains 3 to 15% by weight of water. Composition. 34. The composition of claim 32, wherein the phenolic resin is a solution of novolac in an organic solvent. 35. The anion is bifluoride in an amount of 0.1 to 1.0% based on the weight of the resin.
The composition as described. 36. The composition of claim 32, wherein the anion is citrate in an amount of 0.5-2.5% based on the weight of resin. 37. The composition of claim 32, wherein the anion is fluoride in an amount of 0.1-1% based on the weight of the resin. 38. The composition of claim 32, wherein the anion is malate in an amount of 0.5-2.5% based on the weight of resin. 39. The anion is tartrate in an amount of 0.5-2.5% based on the weight of the resin.
The composition as described. 40. The method of claim 32, wherein the magnesia is deadburned magnesia. 41. In the compound, each alkoxy group has 1 carbon atom.
33. The method of claim 32, wherein the tetraalkoxysilane is 3 to 4. 42. The compound has 1 to 1 carbon atoms in each alkoxy group.
33. The method of claim 32, wherein the partially hydrolyzed tetraalkoxysilane is 3. 43. The following elements: A. Magnesia aggregates; B. Curable phenolic resole having a pH of 4.5-9.5, containing 3-15% by weight of water of the resin, said resin amount being in an amount of about 3-15% by weight, based on the weight of magnesia. Resin solution; C.I. The following elements: a. A compound that provides the composition with aspartate, bifluoride, citrate, fluoride, malate, tartrate and phosphonate anions; and b. Tetraalkoxysilane in which each alkoxy group has 1 to 3 carbons, Partially hydrolyzed tetraalkoxysilane in which each alkoxy group has 1 to 3 carbons, 2-chlorophenol, 4-chlorophenol, 2'-hydroxyacetophenone and 4 '-Hydroxyacetophenone; as well as a compound selected from the group consisting of a mixture of these retarders, a binder-aggregate comprising a mixture of retarder compounds in an amount sufficient to delay the ambient temperature cure of the mixture. Composition. 44. The composition of claim 43, wherein the agglomerate is deadburned magnesia. 45. The composition of claim 43, wherein the agglomerate is hard burned magnesia. 46. About 5 to 35, based on the weight of the agglomerates.
1% to 5% by weight based on the weight of graphite and agglomerates
44. The composition of claim 43, comprising a metal powder selected from the group consisting of aluminum, magnesium and silicon, and an additive selected from the group consisting of mixtures of said additives. 47. The composition of claim 43, wherein the compound providing the anion is an acid. 48. A method of retarding ambient temperature cure of a mixture of a phenolic resole resin and a magnesia agglomerate comprising the following elements: A. Magnesia aggregates; B. 250-5 at pH 5-8.5 and viscosity 25 ° C,
000 cps, about 3% based on the weight of resin
A curable phenolic resole resin solution containing 15% water, said resin amount being sufficient to bind magnesia upon curing of the resin; and C.I. A method comprising providing to the mixture an anion selected from the group consisting of phosphate and oxalate, and admixing a compound in an amount sufficient to retard ambient temperature cure of the mixture. 49. In a method of retarding ambient temperature cure of a mixture of phenolic resole resin and magnesia agglomerates, the following elements: A. Magnesia aggregates; B. PH of about 4.5-9.5 and about 100 at 25 ° C.
Curing having a viscosity of ˜10,000 cps and containing about 3% to 15% water, based on the weight of the resin, wherein the amount of resin is sufficient to bind the agglomerates during resin curing. C. phenolic resole resin solution; C.I. The following elements: a. A compound that provides aspartate, bifluoride, citrate, fluoride, malate, tartrate and phosphonate anions to the mixture; and b. Tetraalkoxysilane in which each alkoxy group has 1 to 3 carbons, Partially hydrolyzed tetraalkoxysilane in which each alkoxy group has 1 to 3 carbons, 2-chlorophenol, 4-chlorophenol, 2'-hydroxyacetophenone and 4 '-Hydroxyacetophenone; as well as a compound selected from the group consisting of mixtures of these retarders, the method comprising admixing a retarder compound in an amount sufficient to delay ambient temperature cure of said mixture. 50. The method according to claim 49, wherein the resin is a condensation product of phenol and formaldehyde, and the catalyst is potassium hydroxide. 51. The method of claim 50, wherein the retarder is malic acid. 52. The method of claim 50, wherein the retarder is citric acid. 53. The method of claim 50, wherein the retarder is tartaric acid. 54. The retarder of claim 50, which is fluoride.
The method described. 55. The retarder of claim 5, which is bifluoride.
The method described in 0.