# United States Patent [19] 

## Finaz et al.

[54] METHOD OF PRODUCING A CELLULAR RESIN SUITABLE FOR USE AS AN INSULATING MATERIAL
[75] Inventors: Gilles Finaz; Robert Michon; Michel Rasclard, all ofLyons, France [73] Assignee: Societe d'Application et de Developpement de Techniques Nouvelles, S.A.D.E.V., Villeurbanne, France
[21] Appl. No.: 533,859
[22] Filed: Sep. 20, 1983
[30] Foreign Application Priority Data

Sep.20, 1982 [FR] France

................................ 82 16071 [51] Int. Cl.3

......................... C08J 9/02; C08G 18/48 [52] U.S. Cl

....................................... 

### 521177; 5211121; 5211131; 5211180 [58] Field ofSearch

.................. 5211180, 121, 131,77
[56] References Cited
U.S. PATENT DOCUMENTS

2,911,380 11/1959 Doedeus

............................. 521/180 [11] 

## Patent Number:

[45] 

## Date of Patent: 

## 4,467,051 Aug. 21, 1984

3,047,518 7/1962 Doedeus et al.

.................... 521/180 3,128,258 4/1964 Doedeus et aI

..................... 521/180 3,274,157 9/1966 Doedeus et al.

.................... 521/180 3,311,573 3/1967 Graham et al.

..................... 521/180 3,311,574 3/1967 Bowering et al.

.................. 521/180 3,311,575 3/1967 Graham et a1.

..................... 521/180 3,415,763 12/1968 Sonnabend

.......................... 521/180

OTHER PUBLICATIONS

Article: Development ofa Canadian Standardfor Urea Formaldehyde Thermal WallInsulation, Thermal Insulation Performances, ASTM STP, 718-1980, pp. 361-394, (Bowles & Shirliffe).
Primary Examiner-Morton Foelak Attorney, Agent, orFirm-Karl F. Ross; Herbert Dubno
[57] ABSTRACT

A cellular foam particularly suitable for use as thermal

or accoustic insulation is producedbythe condensation in an acidic medium in the presence ofa catalyst hardener of methyloldihydroxydiphenylmethylene ether isomers.

15 Claims, No Drawings

### 1 

### 4,467,051

METHOD OF PRODUCING A CELLULAR RESIN SUITABLE FOR USE AS AN INSULATING MATERIAL

FIELD OF THE INVENTION

Our present invention relates to a method ofproducing a cellular or foamed synthetic resin composition resin composition and to the composition which thus results andespecially totheuse ofthecompositionas an insulating material. More particularly, the invention relates to cellular or foamed compositions obtained by the condensation of isomers of methyloldihydroxydiphenylmethylene ether.

BACKGROUND OF THE INVENTION 5 

## 2
D. L. McElroy and R. P. Tye, Editors, American Society for Testing and Materials, 1980, pp 361-394. The description ofthese publicationscanbe found onpage 

### 2 ofthe French text.

These studies have concluded that the**shrink~ge** can be up to about 21% by volume and it can be estimated that such shrinkage ,reduces the thermal performance of the material by 60% with respect to the same material hypothetically filling the original space without shrink10 age. These undesirable 'results have been confirmed by

numerous experiences carried out utilizing urea-formaldehyde foams.

One might expect the polyurethane foams to effec15 tively replace the urea-formaldehyde foams because of their excellent thermal pll'Operties, their desirable meIt is common to provide insulation for buildings, chanical properties, 1m!! theil!' good dimensional stabilespecially residences, and transport vehicles (land vehi- ity. cles, maritime vehicles and aircraft), and for indus,trial In practice, however, it ill fm,md that this ie not the
structuressuchas ducts, utilizing cellular syntheticresin 20 case. For example, it is not possible or mdvantageous to insulating compositions which generally are applied in simply inject such materials in the spacebetween a wall the form ofa liquid foam which reacts and hllll'dens to and a partition because ofthe sharp increase in pressure produce the cellular product. which occurs when this material is injected into III wall.

Thereaction can be carried out in a factory by treat- Theexpaillsion pressure ofthe foam appears tobe ofthe ing the industrial structure tobe insulated or at the site 25 order ofkg/cm2 and the use of such materials require in the case ofbuilding structures, either by casting the support for the walls of the cavities into which the reactive liquid composition in a space to be provided polyurethane foam is introduced. with the insulating material, byinjection ofthe reactive For example, if a metallic structure is filled in the liquid into a cavity tobefilled thereby, orbyprojecting factory with such foams, themetal panelsfrequently are the composition against a surface to be coated, Gener- 30 distorted. Sandwich structures likewise formed with ally speaking these liquid reactive compositions have been urea-fonnakllehyde resins, polyurethane resins, such foams are also distorted or deformed. Ifthe polyepoxy resins or phenol-aldehyde (phenol-formalde- urethane resin is injected between a supporting wall and hyde) resins or combinations thereof. a partition, the partitionis frequently displaced, cracked

Because ofthe simplicity of application, urea-for- 35 or otherwise ruptured in a wholly unacceptable manmaldehyde resins Ilave been widely used for over 20 nero years in EuropeandNorthAmericafor theinsulation of Ofcourse, one can utilize specially reinforced partiprivate domiciles and other structures. tions and other structures adapted to withstand the

Generally the reactive composition is discharged expansion pressures ofpolyurethanebut, ofcourse, this from a machine which proportions the twocomponents 40 can only be done with loss ofeconomic advantages of in a fixed ratio with respect to one another, e.g. a 50/50 the polyurethane foam. proportion by volume. The supply reservoirs of the Furthermore, the polyurethane foams cannot be utimachine thus can contain the two components, one of lized effectively in existing structures without such which is the resin in the form ofan aqueous solution of reinforcements.

a precondensate of urea-formaldehyde containing a 45 Polyurethane fomus suitable for application by proplasticizer. The other composition can be an aqueous jection onto a surface have also been developed, for solution of the catalyst and the foaming agent which example, for insulating terrace roofings, albeit with the

can include an anionic surface active agent in an acid disadvantages discussed above. Furthermore, the moismedium. Thetwocomponentsare mixed, foamed in the ture in concrete or support structures against which the
presence of air and the resulting composition, in the 50 polyurethane foam may be brought, tends to affect the form of a cream having the consistency of shaving hardening or setting of the resin. In the region where
cream, can be cast between slabs, can be injected the foam contacts the support, the properties of the through small holes in the space between partitions and foam differ from those elsewhere. walls, or can be coated onto structures to be provided Another difficulty frequently encountered in the use with insulating layers. 55 of polyurethane foams is the limited temperature at

The foam hardens in about one minute to leave a which it can be applied, namely, between 10· and 30· C. cellular material. Thus in severe temperature extremes as may occur in

Initially the density ofthe foam depending upon the the summer and in the winter, the use ofpolyurethane humidity, is about 40 to 48 kg/m3but after drying over foams is drastically limited.

a period of several days to several weeks, the density 60 Yet another disadvantage of using polyurethane diminishes to a level between 10 and 13 kg/m3. Regret- foams is the flammability characteristics thereof, a distably, significant shrinkage accompanies this reduction advantage which is also found with urea-formaldehyde in density and drying and is responsible for a significant foams. loss in thermal insulating performance ofthe material. The conventional polyurethane foams are somewhat

An extensive study of this subject can be found in 65 flammable and cannot be utilized where there is a danBowles and Shirliffe: Development of a Canadian Stan- ger of ignition. This is especially the case in buildings dardfor Urea Formaldehyde Thermal Wall Insulation, and domiciles and for the insulation ofroof, ceiling and Thermal Insulation Performances, ASTM STP718 and like structures when sandwich panels are provided.

## 3 4,467,051 4 Naturally, various remedies to this problem have minute. With resol resins, while it is possible to modify been developed and, for example, some firms have fab- the reactivity. by various means, e.g. controlling the ricated polyols for use in the production of polyure- concentration of the methylol group, the nature and thane foams whichenable them tobe fire retardant and, concentration of the catalyst and hardener, or other for example, to conform to the M 1 class utilizing the 5 aspects ofthe reaction, it is found that when the duraepiradiation test described in Frenchindustrial standard tion ofcontact is.sufficient for the initial aspect ofthe NF P 

### 92-501. reaction, theexothermicity ofthe reactionis insufficient

However, such foams contain nitrogen, chlorine or to provide, at ambient temperature within an appropribromine or combinations thereof and, upon combina- ate time ofthe order, say, oftwo minutes, a complete tion, emit opaque smoke or highly toxic vapors and 10 drying and hardening ofthe foam. thus, although they are less flammable, upon contact A second disadvantage ofresol based resins used to with a source of combustion, can give rise to other date is thatthe viscosity ofthe resol resin for foaming is health disadvantages. generally between 1,000 and 5,000 centipoises. It 

### is

Epoxy resins havebeen found tobe interesting in the possible to reduce this viscosity to slightly below 1,000 production of thermally insulating foams, although 15 centipoises by increasing the concentration ofwater in their cost is so great that they have been utilized only the product but this reduces the reactivity ofthe resin effectively in industrial apparatus such as steam boilers and diminishes the properties of the fmal product as ofthe like, whichjustify the higher cost. Furthermore, well as its dimensional stability. The viscosities ofthe their combustion characteristics have limited their ap- resol resins whichmustbeused donotpermitthegenerplicability in the same manner as polyurethane foams. 20 ation oflight foams ofthe type which have been found Phenol-aldehyde resins, generally referred to as pheno- to be satisfactory with urea-formaldehyde resins and lic resins, have the advantage that they are exception- indeed it is generally not possible to obtain a final denally resistant tocombustion for materials which are rich sity ofthe material significantly below 30 

### kg/m3 even in carbon and hydrogen. Indeed, it is possible to form under the best conditions. from them foams, which are non-flammable and are in 25 Still another disadvantage of resol-based resins for the M 1 class for the epiradiation test as previously the purposes described is the need to utilize large quandescribed. tities ofhardening agentorcatalyst. Becauseofthepoor

It 

### is for this reason that considerable effort has been reactivity and the higher apparent density ofthe foam, expended in the development of such foams where it is generally necessary to accelerate the reaction by thereis a chanceofcombustion, for example, in building 30 

### utilizing comparably large quantities of hardening
structures and in transport vehicles. agents orcatalysts. Thecompounds are generally acids,

The usual method ofproducing a foam ofa phenolic for example sulfonic acids, and when these are used in resin comprises mixing a resin known as a resol with an excess, they tend to increase the hydrophilic character acidic compound in the presence of a surface active ofthe foam and make the same corrosive. agent and a blowing agent, permitting the mixture to 35 

### Yet another disadvantage of the use of resol based react under the exothermicity of the reaction until a resins for foam insulation is the limited temperature at fluid foam is formed which hardens progressively until which the foam can be generated, generally a temperathe reaction concludes. ture in the range of 10° to. 25° C. Below 10° C., the

Theresol based phenol-aldehyde resins which canbe product is difficult to handle and there is a risk that it foamed in the manner described can be applied by the 40 will solidify or plug the pumps, piping, nozzles and the methods utilized with other resins, e.g. by casting, by mixing head. Furthermore, the reactivity is substanprojection onto a surface and by injection into a cavity.

. tially reduced at temperatures below 10° C. However, because ofa variety ofdifficulties generally Attemperatures about 25° C., thecontrolfo thereacassociated with the formation ofa foam ofsuch resins, tion can be lost. Consequently, one is generally limited the use thereofhas been marginal to date. 45 

### in the time ofapplication ofthe product to a narrower

As a matter of fact, considerable research has gone interval thanthat which has been found to bedisadvaninto the efforts to control the reaction and into the tageous for the use ofurea-formaldehyde resins. production ofarticles utilizing such resins without sig- It

### has also beenfound thatthe resol resins ofconvennificant success. tional types have poorstorage stability ofshelflife. The

For example, resol based phenol-aldehyde resins 50 resins tend to condense autogeneously with increase of have poor reactivity. When a foamed resin is to be

.their viscosity. Thereaction occurs more readily as the produced from two components, it is necessary to pro- storage temperature increases. Resol resins are individe sufficient time for the two components to react in cated to have shelflives less than several weeks. Consethe mold orin the cavity tobe filled orin the device for quently it is difficult to stock the materials at various metering the two components into the mold or cavity. 55 locations or to ship them long distances. However, this time cannotbe excessivebecausethereis Finally, it should be mentioned thatthe conventional always the risk that the mixture will drain from the resol resins produce foamed products which have poor cavity, especially if the walls thereof are porous, as is dimensional stability and which are somewhat brittle. the case in building structures. For urea-formaldehyde It 

### has already been recognized that the mechanical resins, thetime required for the reaction is less than one 60 strength propeI1ies offoamed resins formed from such minute which has been considered to be a suitable time resols are poor and especially that they have extremely period. low tensile strength.

Within this time period, thefoaming reactions should Indeed, when dimensional stability is tested accordbe rapid and hardening should follow directly with a ing 

### to the French standard NFT 56122, i.e. after several sufficient exothermicity to completion and to eliminate 65 cycles including a conditioning phase at ambient temvolative materials. perature and in a relatively constant humidity atmoThus the desirable kinetic curve should increase ex- sphere, followed by a period in an oven, it is noted that ponentiallywithtemperature after aperiod ofaboutone there is a substantial dimensional variance. In suitable

## 5 4,467,051 

## 6 foams, this variation is minimal. A minimum variation under this test is necessary if degredation ofthe foam with time is to be avoided since the test represents an accelerated weathering or aging test. In fact, dimensional variationsunder suchtests shouldbeless than 2% 5 and this value is difficult to guarantee when the foam is made ofa resol resin ofthe type described. HOCH2-ArOH-[CH2-AROH(CH20H)xJy-H



### in which small xrepresents 0 

### or I and thus indicates the number ofmethylol groups which canbe substituted on the aromatic hydroxy moiety; small y is Ii

### highly variable integer representing the polymerization of these units and generally represents from several units to several tens ofunits. OBJECTS OF THE INVENTION The resol resins are thus characterized at a chemical It 

### is, therefore, the principal object of the**pr~sent.** 

### 10 level, by hydroxy aromatic moieties connected to one invention to overcome the disadvantages described another·by methylene groups. A certain number of above. these moieties can comprisein an orthoorpara-position

A more specific object ofthe invention is to provide with respect to the phenolic hydroxyl group, with

a method of making a cellular foam, particularly suit- methylol groups apartfrom all otherreactive functional able for insulation purposes, which canbe applicable in 15 units. situ without any ofthe disadvantages outlined above in The hardening of the resol resin in the presence of connection with resol resins. acid compositions, referred to as hardeners or**~atalysts,**



### Still another object ofthe invention is to provide an is effected by a condensation of the methylol groups improved insulating material. with the hydroxy aromatic moieties belonging to the DESCRIPTION OF THE INVENTION 20 

### resin itselforto the hardener. The hardeners are gener- ally aromatic sulfonic acid and can be simple compounds such as the para-toluene sulfonic acid, hydroxybenzene sulfonic acid, etc, or sulfonic resins such as the condensate ofhydroxy benzene sulfonic acid with formaldehyde. Theseobjects and otherswhichwillbecome apparent hereinafter are attained, in accordance with the present invention which is based upon our discovery that it is possible toproducea cellularproduct wihout anyofthe 25 

### disadvantages ofearlier resol based resins by condensing atleast one isomer ofmethylol-dihydroxy-diphenyldimethylene ether (MDDME) ofthe empirical formula CisHlS04and especiallythe 3-methylol-2,2'-dihydroxydiphenyldimethylene ether ofthe structural formula: 30 

### According to conventional techniques, the hardening reaction with the resol resin gives an insoluble and non-fusible foam. The latter has a three-dimensional reticulate structure with crosslinking ofthe molecules

as aconsequenceofthefact thatthe number ofmethylol
groups per mole ofresol resin is greater than unity.
OH 

### The MDDME is a compound chemically different

# "'~ .COHH2-0.'-

..

# CH20"'~CH20H 

### from the products which are condensed in the conven- 35 tional resol resin and produce condensation products which are likewise different.

Firstly, the MDDME is a mixture ofisomers ofwell

., defmed structures as represented by the formulas given and the 3-methylol-2,4'-dihydroxy-diphenyldimethy- above. By contrast with resol resins, these formulas do lene ether ofthe structural formula: 40 not have any recurrent units and MDDME is readily definable by nuclear magnetic resonance spectrometry

as having a molecular weight of260.

Another important distinction is that the MDDME has a dimethylene ether group (-CH2-0-CH2) 

### 10-

(possibly in a mixture ofthe two isomers). 45 cated between the two aromatic moieties of the compound. The resol resin and its condensate does not contain a corresponding internuclear chain but rather links theinternuclearmoieties by a methylene group whichis neither reactive nor identical to the ether linkage and hencethe hardeningis effective exclusivelybythereaction of methylol groups and the substituted aromatic moieties. Thehardening kinetics ofMDDMEalso proceed differently. Accordingto afeature oftheinvention, themixture is constituted'primarily by or is constituted ofa majority 50 

### of the 3-methylol-2,2'-dihydroxy-diphenyldimethylene ether.

We have found that the use ofisomers ofMDDME permits the condensation to form an insulating foam which can be applied by casting, injection, projection 55 and pulverization.

The transformation ofMDDME into a resin can be effected in a manner similar to that utilized in generating foams from resol resins and utilizing the same hardening or catalytic agents. However, the chemical com- 60 

### position of MDDME, the kinetics .of its reaction, its physical characteristics and the properties ofthe resins obtained differ significantly from those of the resol resins as will be detailed below:

The resol resins are polycondensates':of a hydroxy 65 aromatic compound such as penol with formaldehyde. These resols can be represented by the formula: The hardening ofthe MDDME requires, on the one hand, the reaction with a methylol group (a group which itself cannot contribute to cross-linking and the formation of a network) and, on the other hand, the participation ofthe dimethylene ether group.

For a better appreciation ofthe invention, a reaction scheme for the hardening ofthe MDDME is provided below. However, the process shown is not exclusive, i.e. various other and side reactions may occur depending upon the operating conditions and the reaction'sequence may differ depending upon the nature and concentration of the hardener and the temperature used. Consequently, the explanations below as to the nature ofthe hardening ofthe MDDME should not be considered to be any limitation on the invention.

## 7 4,467,051 

## 8 The hardening ofMDDME was studied at ambient temperature in the presence of acid hardeners which generally were identical to those employed for the hardening ofconventional resol resins. which can contain (with a variability of up to, say, 25%):

MDDME=75% by weight

The polycondensation reaction (I) is initiated at the 5

. methylol group. This reaction is an ionic reaction and Water= 13.5% by weight '2,6-dimethylolphenol=5% by weight mixture ofmethylolphenolisomers=4% by weight phenol-1.2% by weight its velocity is initially proportional tothe concentration ofhydrogen ion. The methylol group condenses with a substituted hydroxyaromatic nucleus with formation of

a methylene bridge and elimination ofone molecule of 10 water (reaction I below).

The reaction is accompanied by the release of heat which accelerates the decomposition in the acid medium ofthe dimethylene ether group with formation of

an internuclear methylene bridge and elimination of a 15 molecule offormaldehyde (reaction II)**belo~.**



### The reaction synergism can be manifested by an acceleration ofthe temperature increase and a vaporization ofby-products ofthe reaction.

Whenthe dehydration is complete, the ionic reaction 20 is terminated although the decomposition of the dimethyl ethergroups cancontinuebya free radical reaction.

The formaldehyde generated by the reactant II has a high reactivity during the ionic reaction phase. It 

### con- 25 denses with two substituted hydroxyaromatic nuclei and thus creates a new methylene bridge with elimination ofa molecule ofwater. It

### participates essentially in

a cross-linking ofthe polycondensate (reaction III below). 30 

# •**H-':H-CH'-r-CH~;::",-cu,OH**

35 H [-ArOH-cH2-0-cH2-ArOH-CH21n-OH 

### + oH20

(II) 

# '\ ! mineral salts (catalyst residues)= 1 % by weight nonidentified impurities=0.3% by weight. TheMDDMEis generallyin theform ofa mixture of the two isomers: 3-methylol-2,2'-dihydroxy-diphenyldimethylene ether

and 3-methylol-2,4'-dihydroxy-diphenyldimethyhme ether.

These two isomers are generally in a weight proportion of9 

### parts ofthe first to I 

### part ofthe second.

The crude products described'above, which is referred to as technical grade MDDME, is a clear liquid of an odor resembling that 

### of phenol. Analyses for
traces ofaldehyde found none. The composition canbe handled in free air without particularrisk to therespiratory tract.

The characteristics ofthe technical grade MDDME

are as follows:

viscosity measured by a Brookfield viscometer at 23°

C.= 170 to 180 centipoises. Density at 25° 'C. d422

### = 1.87 glcm2• 

### pH ofa 10% solution in water=7.4. In spite of its high reactivity, the product can be stored for several months at temperatures below about 20° C. and up to about20° C. without noticeablechange in viscosity. After two months, the viscosity rises only
to about 200 to 220 centipoises.

In order to obtain a foamed composition from the MDDMEtechnical grade product, a foaming agentcan be added which is insoluble and/or we can add a surface-active agent ofthe**emul~ifier** 

### class.

It 

### is desirable 'that the MDDME contain a certain
H [-ArOH-CH212n OH 

### + 0 CH20 

# t 40 

### amount ofwater since this is inlportant for thefoaming.

(III)



### 45

After the ionic step, the nascent formaldehyde released with the water vapor without reacting with the polycondensate, is available as a foaming agent to pro- 50
mote the expansion of the resin. Consequently, the transformation ofthe formaldehyde in cross-linking the polycondensate is incomplete.

The result is a macromolecular reticulate structure which is moderately cross-linked and which explains 55 the particular properties of the cellular resin obtained by condensation of the MDDME, namely, high resilience and a dimensional stability much greaterthan that ofthe resol resins.

Finally, after the reaction is complete there are no 60 longer groups available which can generate formaldehyde even when the composition is brought to an ele-' vated temperature at which pyrolysis may occur. This
too contributes to the high stability ofthe product.

Accordingtotheprocessofthepresentinvention, the 65 MDDMEwhich is polymerized and cross-linked is used in the form ofthe crude products obtained in the fabrication of the MDDME, namely, a composition Naturally this is the case when the technical grade MDDME is used. If

### water is not present, water can be added so that the composition to be foamed contains between 5 and 20% by weight water. '

The foaming agent can be added in an amount of0.1
to 12% by weight ofthe composition to be foamed and is advantageously a liquid having a low boiling point. Preferred foaming agents include:

saturated aliphatic hydrocarbons, e.g. petroleum ether and other mixtures ofhydrocarbons obtained as distillation cuts in the fractional distillation of petroleum, the cut having a distillation curve at ambient pressure running from 30° to 70° C.;

aliphatic ethers, for example ethyl ethers.and especially diethyl ether; and

halogenated hydrocarbons and especially methylene chloride and certain freons such as Freon 11**(fluorotri~** 

### chloromethane) and Freon 113 (1,1,2-trichloro-2,2,I-trifluoroethane).

Itis also more economical to employ a mixture-foaming agent, for example Freon 113 CM which is a mixture ofFreon 113 and methylene chloride.

The surface active agent is intended to produce a stable emulsion of the foaming agent in the aqueous solution oftheMDDME. It

### is utilized in aproportionof 0.01 to 6% by weight ofthe composition.

Preferably the surface'active agents which are used

are nonionic surfactants because these have no unfavor-

## 9 4,467,051 10 able effect on the stability ofthe MDDME

..Ofparticular value are the nonionic surfactants which are polyethoxy ethers of fatty alcohols, alkyl phenols and polysilicones.

Best results are obtained using mixtures ofthe surface 5 active agents prepared such that their hydrophilic-lipophilic equilibrium point or H.L.B. point corresponds to Such sulfonic acids can be employed individually or in mixtures and can be diluted with phenol to control their acidity index and hence their reactivity for foaming and hardening ofthe MDDME.

Specific examples of such hardeners include: phenol sulfonic acids C6H4(0H)(S03H), particularly in

the form ofmixtures oftheir isomersj the cresolsulfonic acids C6lI3(CH3)(0H)(S03H)j the naphthosulfonic acids CloH6(0H)(S03H)j the H.L.B point required for emulsifying the foaming agent in MDDME containing 5 to 20% by weight water.

To emulsify the petroleum ether, an emulsifying agent composition E canbe used whose composition is 10 the dihydroxydiphenylmethane sulfonic acids C6H40H-CH2-C6 H3(0H)(S0 3 H)j

as follows: the dihydroxydiphenylpropane sulfonic acids C6lI40H-C(CH3hC6lI3(OH)(S03H)j condensate of

### 4 moles ofethylene oxide (E.O.) with

oleocetylic alcohol-70% by weight, nonylpehnol condensate with 4 moles of ethylene

oxide (E.O.)-lS%, and the dihydroxydiphenylbutane sulfonic acids C6lIs(OH15 )-C-(CH3)(C2HS)C6H3(0H)(S03H)j and

nonylphenol condensate with 9 moles ethylene oxide-1S%. The MDDME based foam compositions are foamed 20 and hardened bythe addition ofan acid catalysthereinafter referred to as a hardener.

Tests have shown that the velocity ofthe reaction of theMDDMEis, at least in its initial phase, proportional
to the concentration ofhydrogen ions and it is possible 25
toutilize as thehardener, those acids whosedissociation
constant is sufficient to reduce the pH ofwater to4 pH units and preferably below a pH of2.

A significant number of mineral and organic compounds satisfy this requirement and indeed any mineral 30

ororganic acid capable ofreducing thepH to a pH of2

or lower will suffice.

Best results are obtained when the acidity ofthe mixture ofthe MDDMEand hardener is between0.5 and 2 pH units. 35

For the higher pH values, the reaction is slowed and it may be necessary to supply heat from the exterior.

AtpHvalues abovethisrange, thereactionis sharply slowed and it

## may be necessary to provide an external heating source to maintain the reaction. 40

At pH values below this range the reaction becomes difficult to control. Within this pH range the foamed composition of MDDME foams and hardens at initial temperatures between -50 C. and +350C. which permit the formation of the cellular product by conven- 45 tional in situ processes for insulating buildings and the like.

Care may have to be taken to avoid a strong acidity which may be responsible for hydroscopy and a corrosive character ofthe cellular resins which are thus pro- 50 duced. Preferably the acid hardeners act both as catalysts and as polycondensation agents with the MDDME, thereby removing them from availability as free acids

..Consequently, it is advantageous to utilize compositions and reaction conditions such that the 55 fOaming and hardening are satisfactory but the cellular resin contains the least possible amount of free acid compounds and particularly free acid compounds' which are extractable by water.

Thepreferred hardeners are organic sulfonic acids of 60 the following type: containing one or more aromatic nuclei (benzenic, naphthenic) sulfonic acidsj

containing a phenolic hydroxyl group on at least one

ofthenucleij containing one or more sulfonic acid groups on at 65

least one ofthe nucleij and' containing a hydrocarbon chain Cn H2n, where n is an integer, for connecting the nuclei. the polyhydroxyphenylmethylene sulfonic acids H-[C6lI2(OH)(S0 3 H)-CH21n-C6H3(0H)(S03H)j and polysulfonic acids obtianed by partial sulfonation of

liquid novalac resins. Theformula ofthese acidsis similarly totheformulas given previously but the number of sulfonic groups is less than the number of hydroxyphenyl nuclei. The liquid novolac resins are themselves obtained by a condensation ofphenol with formaldehyde in the presence ofan acid catalyst and with a molar ratio ofphenol:formaldehyde greater than 1.

EXAMPLE 1

The foaming composition is obtained by the addition
to 100 parts by weight oftechnicai grade MDDME as defined previously, of emulsifier E as a surface active agent (3 partsbyweight) and 8partsbyweightofpetroleumether. Thehardeneris preparedbymixing 77 parts by weight oftechnical grade phenolsulfonic acid with 23 parts by weight of crystallized phenol containing 10% water. Using a turbine stirrer, for especially vigorous agitation, 1000 g of the foamed composition are mixed with 250 g ofthe hardener. After 20 seconds of agitation, the mixture begins to foam and assumes the
appearance ofa cream.

This cream is cast into a cylindrical cavity having a volume of 100 

### 1. The foam develops intensively and overflows the cylinder. The volatile material is evolved in the form ofa gas and 3 minutes after mixing of the
two components and about 2 minutes after expansion begins, the foam being hot is totally hardened and dry;

Samples are cut from the molded body and tests of properties are carried out with the following results:

apparent density: 10.6 kglm3 j resistance to compression: 0.3 kglcm2 j dimensional stability according to the French standard NFT 56122: variation less than 1 %j thermal conductivity WImK=0.030j fire-retardant tests according to the epiradiation test

previously described: the material is class Ml. The remainder oftheblock is comminuted in a blade grinderto form granules withaparticle sizebetween0.5

cm and 6 cm. The apparent density ofthe granules is 8
to 9 kg/m3. These granules can be filled directly into a space to be thermally insulated.

EXAMPLE 2

Foamable Composition: Technical grade MDDME: 1OO'parts by weightj surface active agent of the silicon!! type (DC 193

marked by Dow-Coming): 2 parts by weightj

### 4,467,051 

## 12 

## 11 trichlorofluoromethane (Freon 11): 2 parts by

weight; 1, 1,2-trifluoro-2,2,I-trichloroethane (Freon 113): 2

parts by weight; orifice toorifice, thereby filling the wall and driving the air from the latter. The foaming time requires about 20 seconds and allows the insulation of60 m2ofwall with

a void thickness of 6 cm per hour. This rate has been methylene chloride: 2.5 parts by weight. Hardener: 5 found to be extremely satisfactory in practice.

The hardener is prepared by sulfonation, with 77 parts by weight of95% sulfuric acid, ofa mixture constituted by 51.5 parts by weight of dihydroxydiphenylmethane and 48.5 parts by weight ofphenol.

Fabrication ofInsulating Panels: 10

Thefoaming composition and the hardener are introduced into respective reservoirs of a two component machine for applying reactive systems with variable volumetric proportions. The ratio of the two compo- 15
nents is set so that 15 partsby weight ofthe hardener is combined with 100 parts by weight of the foaming formulation. The two components are mixed in a dynamic head and are cast in an amount of4.5 kg ofthe composition into a closed parallelopipidal mold having 20 dimensions of3 mXl m X0.06 m.

The casting time is 10 seconds and corresponds for the time for delivery of4.5 kg from the head. After 3 minutes, the mold is opened and the hardened and nonsticky pannel is withdrawn. 25

The pannel has the following characteristics: apparent volumetric mass (apparent density): 24

kg/m3; resistance to compression: 0.6 kglcm2; dimensional stability as measured in the manner de- 30

scribed: variations less than 1 %; thermal conductivity in W/mK: 0.032; flammability test: class M1. A determination of the combustion and pyrolysis products was carried outbyburning 1 g ofthe material 35 in a quartz tube in a tube furnace at 700° C. while passing a current ofair at a constant rate through the tube. The gaseous products were 2800 mg ofcarbondioxide
gas and 330 mg ofcarbon monoxide gas. Nohalogen or cyanide was detected. 40

EXAMPLE 3 Foaming Composition Technical grade MDDME: 100 parts by weight; surfaceactive agentAtmer 171 marketedbytheAtlas 45

Chemical Company: 1.5 parts by weight; trichlorofluoromethane (Freon 11): 2.5 parts by

weight; 1,1,2-trichloro-2,2,I-trifluoroethane (Freon 113): 2.5

parts by weight. 50 Hardener: The hardener ofExample 2: 30 parts by weight; phenolsulfonic acid: 20 parts by weight. Insulation ofDwelling Walls with Evacuation ofAir A machine is used of the type for two component 55 application with a volumetric ratio of 100/30. The two components are charged into the reservoir ofthis machine and are displaced independently via pneumatic pumps through a tubular hose ofa length of 50 m. At the end of this hose, a static mixing piston having air 60 injection is provided to mix the two components and entrain them in an air stream into the wall.

To permit the evacuation ofair within the wall, e.g. between a partition and a structural wall, small orifices
atregularintervals spacedabout 1 m areprovided along 65 the wall. At one end ofthe wall, the end ofthe gun is introduced into the orifices and the mixture is blown into the spacebetweenthe wall. Thegunis moved from The operation is effective at ambient temperatures between -5° C. and +35° C.

Filling ofhollow metallic Structureofa Thickness of 8 cm for Preparation ofa Curtain Wall:

Thetechnique previously described for the insulation ofa dwelling wall is used although here the operation is carried out in the factory. After filling of the hollow metallic wall structure withthe cellular resin, no deformation ofthe metallic structure is noted.

RoofInsulation Theformulations ofthepreviousexamplesareusedin

amachine for injectingtheresinintothespacesbetween thejoists ofa roof. The material is applied against the inner surface ofthe roofto a thickness of20 cm in the single pass.

The apparent density of the cellular resin measured by samples taken from the product show thatthe product has a density of 18 to 20 kg/m3, depending upon thickness; when applied by injection, but about 12 kglm3when applied by expansion after-spreading upon the roofsurfaces.

EXAMPLE4

FoamingComposition: identicaltothatofExample 3; Hardener: identical to that ofExample 2. Insulation by Spraying ofthe Foundation ofa Building

The machine described in Example 3 is modified to deliver a fixed ratio ofthe two components at 100/100 parts by weight. The combination is pulverized and sprayed on the basement to produce a cellular resin having a thickness ofabout 3 cm. The foaming and the hardening appear practically instantaneously so that there is no danger of flow. The apparent volumetric

mass ofthe insulating layer varies between 25 and 35 kg/m3.

.

The compressure resistance ofthe product exceeds 1 kg/cm2.

EXAMPLE 5

Foaming Composition: that ofExample 2; Hardener: sulfonated novolac-type Alveophen 76058

as produced by the SHEBY division ofthe URACHEM. Group.

- Production ofinSulating Panels: The ratio between the two components, namely, the foamlhardener ratio is 100/20.

The method used was that of Example 2 and the casting time was 16 seconds and corresponded to the delivery ofa weightof7.2 kg ofthe product. Theproduct hardened overa period of5minutes. Thecharacteristics ofthe panel are the following:

apparent volumetric mass (apparent density): 38

kg/m3; resistance to compression: 1.2 kglm3; dimensional stability: variation less than 1 %; thermal conductivity inW /mK: 0.034; flammability test: class M1. We claim: 1. A method of producing a cellular resin which comprisesthe steps ofcondensing atleast one methyloldihydroxydiphenylmethylene ether isomer of the empirical formula C1SH1604.

### 4,467,051 

## 14 13 2. Themethod defined in claim 

### 1in whichthe isomer is at least one ofthe following isomers:

the 3-methylol-2,2'-dihYdroxY-diphenylmethylene

ether ofthe formula:

or the**3-methylol~2,4'**-dihydroxy-diphenylmethylene ether ofthe formula:

.

3. Themethod dermed in claim 1wherein said isomer on at least one aromatic nucleus, at least one sulfonic acid group per molecule.

S. Themethoddefinedin claim 

### 1 whereinthe sulfonic acid is selected from the group which cOl!lslists ofphe5 nolsulfonic acids and isomers thereof, cresolsuhonic acids naphthosulfonic acids, dihydroxydiphenylmethane sulfonic acids, dihydroxydiphenylpropane sulfonic acids, dihydroxydiphenylbutane sulfonic acids, polyhydroxyphenylmethylene sulfonic acids and poiy10 sulfonic acids obtained by the partial sulfonation of liquid novolac resins.

9. The method defined in claim 1 wherein the condensation is carried outby mixing the catalyst hardener and a foaming composition containing methylol dihy15 droxydiphenylmethylene ether and thereafter casting the resulting composition.

10. The method defined in claim 1 wherein the condensation is carried outbymixing the catalyst hardener and a foaming composition containing methylol dihy20 droxydiphenylmethylene ether and thereafter projecting theresulting composition ona surface to enable said composition to foam thereon. is present in the form oftechnical grade methylol-dihydroxy-diphenylmethylene etherin a mixture containing methylol dihydroxy-diphenylmethylene ether together 25 with water, methylol phenol and dimethylol phenol in the presence ofa foaming agent, a surface active agent and a hardener. 11. The method defined in claim 1 wherein the condensation is carried outby mixing the catalyst hardener and a foaming composition containing methylol dihydroxydiphenylmethylene ether and thereafter injecting the resulting composition into a wall space adapted to insulate two zones from one another. 4. The method defined in claim 1 wherein the reaction is carriedoutwitha foaming agentcontentof0.1 to 30 12% by weight and a surface active agent content between 0.01 and 6% by weight.

S. The method defmed in claim 1 wherein the foaming agent is a saturated aliphatic hydrocarbon, an aliphatic ether or a halogenated hydrocarbon. 35

6. Themethoddefined in claim 1whereinthe catalyst hardener used is selected to bring the pH during the reaction to below 4.

7. Themethod dermed in claim 6wherein thecatalyst hardener is at least organic sulfonic acid comprising at 40 least one aromatic nucleus, a phenolic hydroxyl group

45

50

55

60

65 12. The method defined in claim 1 wherein the condensation is carried outbymixing the catalyst hardener and a foaming composition containing methylol dihydroxydiphenylmethylene ether and thereafter dispersing the resulting composition and permitting particles thereofto expand and harden.

13. The method defined in claim 9, further comprising comminuting the cast product thus produced to form insulating granules therefrom.

14. The product made by the method ofclaim 1. 15. Insulation between walls made by the method of claim 1. 

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