CA1038528A

CA1038528A - Building material element

Info

Publication number: CA1038528A
Application number: CA195,014A
Authority: CA
Inventors: Volkmar Hilzensauer; Gunther Pflug; Gerald Maresch; Kurt Kirsch; Felix Wehrmann
Original assignee: Isovolta Osterreichische Isolierstoffwerke AG
Current assignee: Isovolta AG
Priority date: 1973-03-16
Filing date: 1974-03-14
Publication date: 1978-09-12
Also published as: FR2221602A1; DK151954C; SE415178B; CH606669A5; NO146501C; NO740900L; NO146501B; BR7402022D0; DE2410605C2; CH605459A5; IT1020553B; JPS5026319A; DK151954B; JPS6030824B2; GB1463613A; DE2410605A1; FR2221602B1

Abstract

ABSTRACT OF THE DISCLOSURE
A building material element comprises a lightweight inorganic material, such as exfoliated vermiculite, expanded perlite, slag wool or fly ash and is an organic resin two component binder of which one component is a combustible resin component, e.g., a phenol resin, and the other component is an incombustible nitrogen-containing resin component, e.g., a urea resin. The element is produced by spraying granules of the inorganic material with the binder and then pressing the granules in a heated press.
Waterglass may be present as an additional binder.

Description

~038S2~
, .
~ield of the Invention The invention relates to inoombustible building material elements whioh have good thermal insulation propert1es, and i partioularly oonoerned with, but not limited to~ building boards.
Description of the Prior Art Inoombustible building material element~ generallg oonsist of inorganio material~. ~or example, shaped elements, suah as boards or blooks, whioh oan be used as light-weight building ~ elements, may be obtained by mixing expanded materials, suoh as expanded mioa, with plaster or oement and by ~uitably shaping the oomposition and allowing it to set or by outting the composition after it has set. The relatively hlgh proporbion of ;~
binding agents in the form of p1asber or oement whioh is neoe0sa~y ; in order to aohieve adeguabe binding of the expanded =aterial0, lead0 in most oa~es to relatively long setting ti=es or to element~
whioh have only poor thermal insulation~properties. In addition,~
building elements of thi~ kind can generally be worlced only with difficulty or with considerable wear of the material. ~ -In Swiss Patent Speoifioatlon ~o. 519,639 it has been ~ propo0ed to mix expanded mica and an inorganio inoombusbible binder in the volumebrio proportion of 9:1, and to press the mixture to ;~
form building elements. The amount of`binder required in thi0 prooe0s is also relatively great.
, : ~
Summary of the In~ention 25~ Aooording to one~aspeot of the pre0ent inventlon there is~
provided a building material elemenb oomprising a lightweight inoxganic material, and~an organio re0in two-oomponent binder for aid material, one component of sald binder being a oombustible resin oomponent and the other oomponent of 0aid binder being an 3O~ inoo=busbible nibrogen-oonbaini~g resin oo=ponent.

.,i ~ r '

2 ~
: : :
1~::

~ 38528 The present building elements, which are preferably in the for~ of building boards, thus contain a resin-bound inorganic material, suoh as exfoliated vermiculite, expanded perlite, slag wool, fly ash, in which a relatively small proportion of the organic binder is used, while, despite the use of the organic binder, an incombustible building element is ~;
obtained which has good hea-t inRulation properties and whioh in addition provides good æound insulation.
The combustible resin component is preferably a phenol resin and the incombustible nitrogen-containing resin component is preferably a urea resin, in which case, the content of the urea resin component in the resin mixture is desirably from 10 to 25 mole pex cent.
I~ a fire should occur, the action of heat on a urea resin in the ~;
pre~ent building element will produce an atmosphere having a high nitrogen content, which will prevent the comb~stion of the combus-tible resin component (phenol resin) to ~uch an extent that carbonisation of the resin component does not occur but only a superficial charring as the result of which a dense thermally stable layer of carbon is formed on the surface of the building.element.
Exfoliated vermiculite, expanded perlite, expanded clay, or mixtures thereof are preferred e~amples of expanded materials which may be used in forming the present building elements.
In addition to the organio binder, the presen-t building material - element preferably contains waterglass as an additional binder, theproportion of waterglass in the entire quantity of binder, calculated as ~` .
solid material, preferably being at least l~o bv weight~ ~he addition of -;~-waterglass to the binder has, among other results, the effect of increasing the fire resistance of the building material element~
According to another aspect of the present invention there is provided

- 3 ~
~ I . . .

. . :. . -: - , . ,. : - ..................... ~
- -, :: , -: :::: ~ . , , , :

~385Z~
a procesa for the production of a building material element, wherein granules of a lightweight inorganio material are spxayed, while being stirred, with an organio re~in two-oomponent binder, in an amount of from 2 to 30% by weight o~ binder calculated as a dry solid, based on weight of inorganic material, suoh binder ha~ing one component which i~ a combustible resin ¢omponent and another component whichis an incombustible nitrogen-containing re~in component, and wherein the coated granules are moulded or pre~sed to form the element in a heated press.
~he moisture content of the granules coated with binder is advantageously reduced to below 7% and the treated granules then pressed in a preaa heated by high frequency.
In one embodiment of the present process, the granules treated with binder may be precompreased at room temperature in a mould to form a ~elf-suataining body which is then removed from the mould, and thereupon prea~ed and bhermally oured. ~he body removed from the mould has sufficient strength re~ulting from the preoompression to form a atable bisouit which oan be introduoed into the press without xequiring speoial tranaport means, suoh as plates or belts.
If desired, strengthening or reinforcing elements may be introduced during the spraying of the granules with the binder, whereupon the ~ranulea are preferabIy preoompressed and then pre~sed into the final building element. Glass fibres, glasa filaments, and bhe like are parbioularly suitable as strengthening or reinforcing elements.
.. .
~he preaent building material element, partioularly in the form of a building board, oan be integrated with similar boards to form a multi-layer board direct during ita manufaoture, and a multi-layer board of this kind oan be produoed by pressing the gxanules treated with binder, or the preoompressed biacuit, with oover sheets previously 3 treated with binder or together with external cover boarda. ~hrough : ~ ' :", ~038~
a multi-layer ¢onstruction of this kind, for exa~ple u3ing paper, glass fleece, aluminium foil, or the like, an improvement of the mechanical stxength of the resulting board i9 achieved.
If the present building material element is to oontain water~
glass a~ an additional binder, the granulate may be sprayed with water-glasa prefera~bly using the spraying means 3epara,te from those u~ed for spraying the organic binder, whereafter the granules, treated with binders and ¢ontaining an expanded material, are prqferably first precompressed and then shaped or pressed into mouldings in a heated hydrauli¢ press.
' ~ It is true that ~ ~ Patent Speoifioation ~o. 187,051 has disclosed a b~ilding board which is composed of expanded mica with waterglass a~ a binder. When an inorganic binder, such as waterglass, is used, lt is however, generally necessary to u~e a ~ub~tantially hlgher proportion of binder than when an organio binder i~ employed. ~urther- ;~
more, with binders suoh as waterglass, whioh give up a xelatively large amount of water on setting, the diffioulty of removing thi~ water suffioiently quiokly arises, and this generally leads to relatively long pressing times. ~heiuse of waterglass as a binder for building elements has, therefore, not been very widespread.
In the present procesa in whioh both an organic binder and water- ~ ~
glass are used, a sub~tantially ~maller amount of watergla~s i9 required ?
than in the abovementioned prooes~ desoribed in~e ~ Patent Specification No. 187,051, since a large part of the binding action is supplied by the organio binder. Sinoe, however, the organio binder fraotion gives up only relatively small amounts of water on setting, substantially smaller amounts of water have to be removed in this -embodiment of the present prooess and it is possible to manage with substaniially shorter heating times than would be the oase for a building material element in whioh uaterglas~ wa~ the only binder. :

- ,~

, . .

~ ecause the expanded material granules are sprayed separately with the organic binder and with the waterglass, a binder film i8 produced which containa both these products, namely ~: :
-the organic binder and the waterglass. In this binder film there now 5 takes place a precipitation reaction by which the film iæ co~verted to a jelly-llke consistency. It is found that, after precompression, the granule~ coated in this manner produce substantially ~tronger preformed elements than in the case of coating with the organic binder or waterglass alone.
10Description of the Preferred Embodiments ~ ~ ;
~he invention will now be illustrated by the following Examples~
Example 1:
600 litres (50 kg.) of exfoliated vermiculite of a ~rain size 0.5 to 3 mm. are sprayed in a free-fall mixer with 12 litres of a 7~/0 15aqueous resin mixture conaisting of 85 mole % of a phenol-formaldeh~de resin and 15 mole % of a urea-formaldehyde resin, in such a manner that the grains of the exfoliated vermiculite are uniformly wetted. ~he resin-coated granulate obtained in this manner is compressed-uniformly in an unheated prepressing apparatus at a pressure of about 1.5 kp./cm2 to 5~/0 20of its original bulk volume, whereby a transportable moulded produot is obtained. ~he latter is thereupon cured in a press equipped with a high frequenoy and/or thermal heating system, together with oover sheets of kraft paper coated with resin on one side, at a pressure of from 2 to kp./cm.2 and with a press temperature of 150 to 170C.. ~he moulded product is removed from the mould in the hot state ana c~t to the desired size. ~;
In a test for combustibility, no asphyxiating or combustible vapours or gases occurred, the material glowed when subjected to the action of a flame, in aooordanoe with the temperature produced, and after :
,, .

~1385Z8 ~ ; ~
removal of the flame, no ther burnin~ could be ob~erved.
Ihe building material produced in accordance with -this Example nas a unit weight of 350 to 400 kg./m3 and posses6es a bending strength of from 40 to 50 kg./cm.2. ~ ;
Example 2 -~or the production of a mixed resin solution 1 kilomole of ~-. ~
phenol (94 kg.), 0.15 kilomole of urea (~ kg.) and 1.6 kilole of formaldehyde (120 kg., 40 weight % solution) are catalysed with sodium hydroxide solution and condensed to form a mixed resin at 80 to 100C
~he resin æolution is thereupon concentrated to a solids content of 70/o by weight by vacuum distillation.
600 litres (50 kg.) of exfoliated vermiculite of a grain size .. ~ . .
0.5 to 3 mm. are sprayed in a free-fall mixer with 12 litres of this 70/0 mixed resin solubion in a manner ~imilar to that desoribed i~
Example 1.
~he granulate aoated in this manner is then further processed as .
desaribed in ~xample 1.
Example 3 600 litres (15 kg.) of exfoliated vermaculite of a grain size 0.5 to 3 mm. are sprayed in a free-fall mixer with 5.4 litres (6.21 kg.) of the mixed resin æolution deæcribed in Example 2 and, u~ing a æeparate ~praying deviae, with 5.4 litres (8.10 kg.) of sodium waterglass of 48 50 ~é, in such a manner that the grainæ of the exfoliated vermiculite are uniformlg wetted. The granulate coated in this manner iæ aompressed unifo~mlg in an unheated prepressing apparatus at a pressure of 1.5 kp./cm.
to 5~/o of its original bulk volume, whereby a transportable moulded product is obtained. The latter is thereupon cured in a press equipped witn a ;
high frequenay and/or thermal heating system, together with cover sheets of kraft paper coated with resin on one side, at a presæure of from 2-3 kp./cm.2 and with a press temperature of 150 to 170C... The moulded ~ 7 ~ ~` ;
. . ~:

~0~3528 ~ ~
product is removed from the mould in the hot state and cut to the desired size.
The board-like building element produced in acco~dance with this Example has a unit weight of 350 ot 400 kg./m.3 and posaesses a bending strength of from 45 to 55 kp./cm.2.
Example 4 ~he procedure described in Example 3, i8 f'ollowed with the exception that 600 litres (50 kg.) of exfoliated ~er~iculite are used with only 4.2 litres (4.83 kg.) of mixed resin solution but with a higher proportion of waterglass, namely 6.7 litres (10.05 kg.);of sodium waterglass, the quality being the same in each case as in Example 3.
~he building material element obtained ha~ a unit weight of 350 to 400 kg./m3 and a bending ~trength of 45 to 55 kp./cm2 as in ~xample 3, but beoau~e of the higher proportion of watiglas~ in the bi~der ha~ greater re~istance to fire.
,~

, ' : :' .

_ 8 -,i ~ .

Claims

WHAT IS CLAIMED IS:-

1. A building material element, comprising a lightweight inorganic material selected from the group consisting of granular, powdery and fibrous inorganic material, and a binder for said material, said binder being an organic resin two-component binder, one component of said binder being a combustible resin component and the other component of said binder being an incombustible nitrogen-containing resin component.

2. The element of Claim 1, wherein the combustible resin component is a phenol resin.

3. The element of Claim 1, wherein the incombustible nitrogen-containing resin component is a urea resin.

4. The element of Claim 3, wherein the content of urea resin in said resin binder in from 10 to 25 mole %.

5. The element of Claim 1, wherein the organic resin binder is a mixture of the separate components.

6. The element of Claim 1, wherein the organic resin binder is a mixed resin in which the two components are copolymerised.

7. The element of Claim 1, wherein the element further comprises waterglass as an additional binder.

8. The element of Claim 7, wherein the proportion of waterglass in the total amount of binder, calculated as solid material, is at least 10% by weight.

9. The element of Claim 1, wherein the lightweight inorganic material is selected from the group consisting of exfoliated vermiculite, expanded perlite, slagwool and fly ash.

10. The element of Claim 1, in the form of a building board.

11. A process for the production of a building material element, comprising the steps of providing granules of a lightweight inorganic material selected from the group consisting of granular, powdery and fibrous inorganic materials, spraying said granules, while stirring them, with an organic resin two-component binder in an amount of from 2 to 30% by weight of said binder calculated as dry solid, based on the weight of inorganic material, said binder having one component which is a combustible resin component and another which is an incombustible nitrogen-containing resin component, and pressing the coated granules in a heated press to form said element.

12. The process of Claim 11, wherein the moisture content of the coated granules is reduced to below 7% and then pressed in a press heated by high frequency.

13. The process of Claim 11, wherein the coated granules are precompressed in a mould at room temperature to form a self-sustaining body which is then pressed in said heated press.

14. The process of Claim 11, wherein reinforcing elements are introduced during the spraying of the granules.

15. The process of Claim 11, wherein the coated granules are pressed together with covers selected from the group consisting of outer cover boards and cover sheets previously coated with binder.

16. The process of Claim 13 wherein the self-sustaining body is pressed together with covers selected from the group consisting of outer cover boards and cover sheets previously coated with binder.

17. The process of Claim 11, wherein, during the spraying of the granules with the organic binder, the granules are additionally sprayed with waterglass by separate spraying means.

18. The process of Claim 11, wherein the combustible resin component is a phenol resin and the nitrogen-containing resin component is a urea resin.

19. The process of Claim 11, wherein the lightweight inorganic material is selected from the group consisting of exfoliated vermioulite, expanded perlite, slag wool and fly ash.