GB2054455A

GB2054455A - Non-flammable light-weight composite material and method of producing the same

Info

Publication number: GB2054455A
Application number: GB7931448A
Authority: GB
Original assignee: Nitta Belt KK
Current assignee: Nitta Corp
Priority date: 1979-07-17
Filing date: 1979-09-11
Publication date: 1981-02-18
Also published as: DE2933095A1; GB2054455B; DE2933095C2; JPS5614482A; JPS6047100B2

Abstract

A moulded non-flammable light- weight composite material comprises a layer containing a fly ash balloon, aluminium hydroxide, thermosetting resin, fibrous reinforcing agent and coupling agent in specified proportions, laminated between layers of thermosetting resin impregnated non-woven fabric. The composite material is produced by mixing the components of the first mentioned layer and kneading the mixture, moulding the kneaded mixture into a plate-like article applying to top and bottom surfaces of the article respective layers of thin non-woven fabric impregnated with thermosetting resin, and laminating and moulding the layers.

Description

SPECIFICATION Non-flammable light-weight composite material and method of producing the same This invention relates to a non-fiammable light-weight composite material and method of producing the same.

The promotion of the construction of high-level buildings has created a demand for light-weight building materials which can be used in practice without problems arising due to insufficient mechanical strength. A further demand is for high quality building materials. Another important demand in the building construction field is for building materials which are non-flammable with the aim of minimizing damage resulting from fire especially in high population density buildings or areas.

Under the existing circumstances, however, a single building material satisfying all the aforesaid demands is not yet available, and in most cases, if the material is light-weight, the mechanical strength thereof to the extent capable of making it suitable for practical use is difficult, if not impossible, to attain. In order to increase the vaiue of building materials which, in use, are exposed to view, the colour tone thereof may be accentuated or an uneven rugged pattern such as a sculptural wall painting applied, or a combination thereof employed. With respect to the colour tone, satisfactory colour tones have been developed through printing technology.However, with respect to the creation of suitably rugged patterns satisfactory molding materials are not yet known capable of being formed with recesses having depths of up to 50% of the maximum thickness of the article, and which are uneven, are susceptible to volume production and can be applied in a wide range of design patterns.

According to one aspect of the present invention we provide a method of producing a non-flammable, light-weight composite material comprising (i) forming a mixture containing a) fly ash balloon and aluminium hydroxide in a weight ratio in the range of from 20:80 to 60:40 b) thermosetting resin in a weight ratio with respect to the total components defined in (i), or 3:97 to 15:85 c) 0.5 to 80 parts by weight in total of fibrous reinforcing agent, coupling agent and possibly inorganic filler and the like, per 100 parts byweightofthethermosetting resin; (ii) kneading the mixture; (iii) moulding the kneaded mixture into a plate-like article; (iv) applying to top and bottom surfaces of the article respective layers of thin non-woven fabric impregnated with thermosetting resin; (v) Laminating and moulding the layers.

According to another aspect of the invention we provide a molded, non-flammable light-weight article comprising thin layers of thermosetting resin impregnated with non-woven fabric laminated to respective surfaces of a base layer composed of a mixture comprising a) fly ash balloon and aluminium hydroxide in a weight ratio of from 20:80 to 60:40 b) thermosetting resin in a weight ratio, with respect to the total components defined in (i) of 3:97 to 15:85 c) 0.5 to 80 parts by weight in total of fibrous reinforcing agent, coupling agent and possibly inorganic filler and the like, per 100 parts by weight of the thermosetting resin.

In the following description the article obtained by molding article from (iii) will be referred to as the "base layer".

Preferred are fly ash balloon produced using. coal as a raw material, such as those sold under the trade mark ARMOSPHERS, FILITE, and CENOLITE. We have found that the use of fly ash balloon may be used in preferred embodiments of our invention as ingredient of building members to obtain building members which are light-weight and high in structural strength. The most noteworthy characteristic of the fly ash balloon mentioned above lies in that unlike other volcanic hollow spheres such as other silas balloons, the former is close to a true sphere and has a relatively thicker spherical shell body, thereby providing increased strength and reducing the amount of oil which can be absorbed.

Referring, by way of example to the drawings, Figure lisa photograph (enlargment x33) of an assembly of fly ash balloons sold under the trade mark ARMOSPHERE: Figure 2 by way of contrast is a photograph of the same degree of enlargement of fine hollow "spheroids" obtained from volcanic ash.

According to a preferred embodiment of the invention the laminating and molding are carried out in a single stage operation.

In the practice of the invention the base layer is thus always initially molded prior to the final molding thereof, while the final molding is carried out always upon the three components of surface layer, base layer and reverse layer, preferably in the following manner: (a) After the preliminary molded surface layer, base layer and reverse layer have been laminated together, they are charged into a mold for final molding; or (b) The initially molded base layer, the surface layer and the reverse layer are charged into the mold and placed one over the other in the appropriate order for laminating and molding in a single stage operation.

The initially molded article and the two sheets are preferably subjected, in the mold, to heat pressure molding for 5 to 10 minutes at a temperature in the range of from 150 to 17000 and at 5 to 50kg/cm2. The upper die will usually be such as to give a suitable rugged non-uniform pattern to the finished product: the rugged pattern in preferred forms may have recessed portions of up to 50% of the maximum thickness of the article. Extremely deep embossing is possible in some embodiments of the invention under low pressure molding as described above because of the fact that the kneaded material, containing fly ash balloon is bulky with the result that the initially molded article is of relatively large volume and does not require a large compressive force for molding to a desired configuration.In preferred embodiments of the practice of the invention it is possible to obtain a light-weight composite material of attractive appearance, efficiently, without the high cost that generally results using the number of complicated steps required when coating processes are employed; loss of coating material; and significant problems such as environmental contamination resulting from volatilization of solvent or the like.

Preferably, the weight ratio of the fly ash balloon to aluminium hydroxide is in the range of from 20/80 to 60/40. If the relative content of fly ash balloon is less than 20 weight parts, light-weight characteristics of the composite material becomes impaired. On the other hand, if the relative content of fly ash balloon exceeds 60 weight parts, the non-flammable effect provided by the aluminium hydroxide is reduced.

The weight ratio between the fly ash balloon and aluminium hydroxide taken together and the thermosetting resin should be in the range of from 97/3 to 85/15. If the relative content of the resin is less than 3 weight parts, it is not possible to obtain satisfactory coupling forces, whereas if the relative content exceeds 15 weight parts it becomes difficult, if not impossible, to obtain a non-flammable material.

The total amount of the fibrous reinforcing agent, coupling agent and inorganic filling agent and the like should be restrained within the range of from 0.5 to 80 weight parts with respect to 100 weight parts of thermosetting resin: if the amount exceeds the upper limit of the aforesaid range, the coupling force is too small while if it is less than the lower limit of the aforesaid range, the efficiency is insufficient.

Thermosetting resins which can be used in the practice of the present invention include phenol resin, urea resin, melamine resin, xylene resin, resorcinol resin and their co-condensation resins or mixtures thereof.

The fine hollow spherical bodies to be used in the present invention include for example fly ash balloons produced using, as raw material, coals for instance those sold under the trade marks ARMOPHARE, FERRITE, and CENORITE, and which typically have the physical properties and chemical ingredients as given in Table 1 and Table 2 below.

TABLE 1 Physical properties Shape Fine hollow sphere Colour Greyish white Bulk specific gravity (g)cm2) 0.3 - 0.4 Apparent specific gravity (g)cm2) 0.6 - 0.7 Grain size (u) 20 - 250 Thickness of shell of sphere 2-20 Melting point ("C) 1,200 Thermal conductivity 0.07 (Kcal/mh"C) 50% breakdown hydrostatic pressure (kg/cm") 100-120 Water absorptivity (%) less than 0.05 Hardness (Mohs hardness) 5 TABLE 2 Chemical composition Silica (O2) 55 - 60% Alumina (awl203) 25 - 30% Iron oxide Less than 5% Alkali (Na2O, K2O) 0.5 - 4% Others (CaO, MgO, ...... etc) Small amount Unlike other sorts of fine hollow spherical bodies, the aforementioned fly ash balloons are in the form of a true sphere (see Figures 1 and 2) and have relatively thick shells compared to others obtained from sources other than fly ash thereby having relatively greater strength and thus, enabling the production of non-flammable composite materials which have high strength while being of light-weight. In addition, as will be apparent when the resin is mixed with various fine hollow spherical bodies all at the same weight ratio, fly ash balloon may be kneaded with only an extremely small amount of resin as compared to the other sorts of fine hollow spherical bodies, and since the amount of oil absorbed is small this further assists in achieving non-flammable characteristics for the material.

Fibrous reinforcing agents which may be used include for example glass fibers, carbon fibers, gypsum fibers, asbestos, and phenol resin fibers: inorganic filling agents which may be used include for example silica, diatomaceous earth, calcium carbonate, gypsum, mica, clay, talc, graphite carbon black, cement, antimony oxide and metal powder.

Coupling agents which may be used include for example methacrylatechromichrolide, and silane coupling agents, e.g.ss- 3, 4, - epoxycyclohexylethyltrimethoxysiiane, N - p (aminoethyl) - y - aminopropyltrimethoxysilane, y - aminopropyltrimethoxysilane, y- chloropropyltrimethoxysilane, vinyl - tris (ss - methoxiethoxy silane, y - glycidoxypropyltrimethoxysilane, y - methacryloxypropyltrimethoxysilane, y mercaptopropy Itrimethoxysilane, y- aminopropyltriethoxysilane, y- ureidopropyltriethoxysilane, etc.

Impregnatable materials most suitably used are thin nonwoven fabrics or sheet material, in the range of from 50 to 300 us formed of inorganic fibers and organic fibers. Those which are thinner than 50 y make it difficult to form deep rugged patterns, often resulting in breakage. Conversely, those which are thicker than 300 L do not stretch easiiy so that a sharp pattern portion becomes rounded in the finished product, thus faiiing to make the best use of the mold design.

The following examples serve to illustrate the invention.

Example 1 50 weight parts of fly ash balloon (sold under the trade mark ARMOSPHERES) and 50 weight parts of aluminium hydroxide were added to 8.5 weight parts of phenol resin, 60 weights parts in total of silane coupling agent and chopped fibreglass strands were added to the resin; the mixture was fully kneaded, and thereafter a granular material obtained by pulverizing the resulting kneaded material was introduced into a mold of required dimension and pressed, at a temperature in the range of from 80 to 100"C, at which temperature the resin does not fully harden, for a period in the range from several seconds to several minutes to produce a molded article which is sufficiently consolidated to permit it to be transported.On one surface of the thus molded article was placed a sheet of glass paper impregnated with a melamine urea co-condensation resin which had previously been compounded with copper powder, coloured titanium oxide (yellow) and phthalocyanine-green and subsequently dried; on the reverse side of the molded article was spread a sheet of glass paper impregnated with only a melamine urea co-condensation resin and subsequently dried, pressing of the article and glass paper sheets was then carried out at 80 - 1000C for 30 seconds to form a laminate of the article and sheets which is sufficiently integrated to be transportable. The thus integrated laminate is inserted into a mold provided with an upper die shaped to provide a rugged, non-uniform pattern of desired design.Heated pressure molding was carried out at 150 to 1700C and 35 - 45 kg/cm2 for 8 minutes to produce a light-weight composite material whose bulk specific gravity is 0.9 and bending strength 135.2 kg/cm2 and which has satisfactory and regular colour tone and an attractive physical appearance.

Example 2 60 weight parts of fly ash balloon (sold under the trade mark ARMOSPHERES) and 40 weight parts of aluminium hydroxide were added to 10 weight parts of xylene resin; 80 weight parts in total of chopped glass fibre strands, silane coupling agent and mica were also added to the resin, and the resulting mixture was kneaded. The kneaded material was then introduced into a mold of required dimension and pressed for one minute at a temperature in the range of from 80 to 100 C, at which temperature the resin does not fully harden to produce a molded article which is of sufficient strength to permit it to be transported.On one surface of the thus molded article was placed a sheet of glass paper impregnated with a melamine resin which had previously been compounded with copper powder, red oxide and carbon black and subsequently dried; on the other side was spread a sheet of glass paper impregnated with xylene resin and subsequently dried. The resulting sandwich is inserted into a mold provided with an upper die with a rugged non-uniform pattern of desired design, and is heat pressure molded at 150 to 170"C and 35 - 45 kg/cm2 for ten minutes to produce a light-weight composite material having a bulk specific gravity of 0.85 and bending strength 114.2 kg/cm2. The article had a satisfactory and regular colour tone and an attractive physical appearance.

Example 3 25 weight parts of fly ash balloon (sold under the trade mark ARMOSPHERES) and 75 weight parts of aluminium hydroxide were added to 12 weight parts of phenol resin. 50 weight parts in total of gypsum fibers, silane coupling agent and kaolin were also added to the resin, and the mixture was kneaded; thereafter, the kneaded material was introduced into a mold of required dimension and pressed at a temperature of from 80 to 1 OO"C for 30 seconds to obtain a molded article which is of sufficient strength for transportation. On one surface of the thus preliminary molded article was placed a sheet of glass paper impregnated with a malamine urea co-condensation resin which had previously been compounded with copper powder, chrome oxide and phthalocyanine-green and subsequently dried.On the other side thereof of the molded article was spread a sheet of glass paper impregnated with phenol resin and subsequently dried. The resulting sandwich was inserted into a mold provided with an upper die with a rugged non-uniform pattern of desired design, heat pressure molding was carried out at 150-170 cand 35-45 kg/cm2 for 8 minutes to produce a light-weight composition material having a bulk specific gravity of 1.15 and bending strength 125.4 kg/cm2 and having a satisfactory surface pattern.

Example 4 40 weight parts of fly ash balloon (sold under the trade mark ARMOSPHERE) and 60 weight parts of aluminium hydroxide were added to 6.5 weight parts of phenol resin 50 weight parts in total of chopped glass fiber strands and silane coupling agent were added to the resin. The mixture was fully kneaded, and thereafter, a procedure simiiar to that shown in Example 1 was carried out to produce a light-weight composite material having a bulk specific gravity of 0.98 and bending strength 99.3 kg/cm2 and having a satisfactory surface appearance.

As a result of test conducted on the light-weight composite materials obtained from the above-mentioned Examples 1-4 in accordance with JIS A - 1321, both the surface test and the base material test proved to give acceptable results.

Comparison test 1 An attempt was made to repeat Example 1 but this time using silane balloon in place of the "armosphere" fly ash balloons. It was found impossible to effect kneading because the degree of wetting caused by resin was insufficient.

Also, a large quantity of silas balloons have been broken during the kneading.

Comparison Test2 An attempt was made to repeat Example 4 using a glass microballoon (made by Emerson Cumming Co.) in place of the "armophere" fly ash balloons. It was found impossible to effect kneading because wetting caused by resin was insufficient and in addition, a considerable quantity of the glass microballoons were shattered.

Comparison Example 3 An attempt was made to repeat Example 2 using a silica balloon in place of the "ARMOSPHERE" fly ash balloons. It was found impossible to effect kneading because of insufficient wetting by the resin. It was also found that a considerable quantity of silica balloons had been shattered.

The operation, effects and advantages of preferred embodiments of the present invention may be summarized as follows: (a) Since a mixture of fly ash balloon and aluminium hydroxide forms the main ingredient of the base layer, a high degree of a non-inflammability combined with light-weight and high strength is achieved.

It will be noted that the fly ash balloon provides characteristics of light-weight and high strength whilst aluminium hydroxide is of course, non-inflammable.

(b) Since the fly ash balloon absorbs only a small amount of oil only a small quantity of resin is required to enable kneading to be carried out. Accordingly, the quantity of thermoplastic resin which forms a component of the base layer is relatively small and in consequence the proportions of aluminium hydroxide and fly ash balloon can be increased to further enhance the non-inflammable light-weight characteristics of the final material.

(c) The coupling agent is used to strengthen the coupling force between the resin and the aluminium hydroxide and fly ash balloon, thereby to provide a full integration of the components of the base layer.

If the resin only is used, the coupling between the aluminium hydroxide and fly ash balloon is not always sufficient, and the bending strength of the final product may not be sufficient either.

(d) By coating the two sides of the base layer each with a thin impregnated nonwoven fabric, protection of the base layer is provided and enables the formation of desired surface effects.

B. Concerning the method of manufacture of the materials: (a) Since the surface layer, base layer and reverse layer are finally molded after an initial or preliminary molding, it is possible to avoid the generation of gases when the final molding is carried out and to prevent the surface from being roughened in this way.

In addition, the final molding may be accomplished securely and readily, and displacement of the various layers is less likely to occur.

(b) By initial or preliminary molding it is not only possible to produce a product, integrally molded but, at the same time, if they are subjected to embossing molding, it is possible to form deep recesses at low pressure.

The reason is that at the time of preliminary molding the kneaded article of the base layer is of large bulk, and thus the recesses may be formed simultaneously with compression.

Further, the fly ash balloon is never broken since it has sufficient strength to resist the necessary embossing pressures.

Claims

1. A method of producing a non-flamable, light-weight composite material comprising (i) forming a mixture containing a) fly ash balloon and aluminium hydroxide in a weight ratio in the range of from 20:80 to 60:40 b) thermosetting resin in a weight ratio, with respect to the total components defined in (i), of 3:97 to 15:85 c) 0.5 to 80 parts by weight in total of fibrous reinforcing agent, coupling agent and possibly inorganic filler and the like. per 100 parts by weight of the thermosetting resin; (ii) kneading the mixture; (iii) moulding the kneaded mixture into a plate-like article; (iv) applying to top and bottom surfaces of the article respective layers of thin non-woven fabric impregnated with thermosetting resin; (v) Laminating and moulding the layers.

2. A method according to Claim 1 in which the laminating and moulding are carried out in a single stage operation.

3. A method according to Claim 1, wherein the layers are first laminated and the resulting laminate is moulded.

4. A method according to any one of Claims 1 to 3, wherein at least one of said layers of fabric is 50-300Ci in thickness.

5. A method according to Claim 4, wherein the layers of fabric are of substantially the same thickness.

6. A method according to any one of Claims 1 to 5, wherein one of said layers of fabric is impregnated with resin that has been compounded with at least one of metal powder, pigment and dye.

7. A method according to any one of the preceding claims wherein the fabric layers are dried after being applied to the article.

8. A method according to any one of the preceding claims wherein the single stage moulding operation is carried out using a mould which provides an embossed, rugged pattern on the surface of the laminated article.

9. A method for the production of a non-flammable light-weight composite material, substantially as described herein with reference to any one of Examples 1 to 4.

10. A moulded, non-flammable light-weight article comprising thin layers of thermosetting resin impregnated non-woven fabric laminated to respective surfaces of a base layer composed of a mixture comprising a) fly ash balloon and aluminium hydroxide in a weight ratio of from 20.80 to 60:40 b) thermosetting resin in a weight ratio, with respect to the total components defined in (i) of 3:97 to 15:85 c) 0.5 to 80 parts by weight in total of fibrous reinforcing agent, coupling agent and possibly inorganic filler and the like, per 100 parts by weight of the thermosetting resin.

11. An article according to Claim 10, wherein at least one of the fabric layers is 50-300y in thickness.

12. An article according to Claim 11, wherein the two layers are of substantially the same thickness.

13. An article according to Claim 10, 11 or 12, wherein one of the fabric layers is impregnated with resin that has been compounded with at least one of metal powder, pigment and dye.

14. An article according to any one of Claims 10 to 13, wherein one surface has a rugged pattern with deeply embossed recesses therein.

15. A moulded light-weight non-flammable article, substantially as described herein with reference to any one of Examples 1 to 4.

16. A method of producing non-flammable light-weight composite material comprising (i) mixing fly ash balloon with aluminium hydroxide in weight ratio in the range of from 20:80 to 60:40 (ii) adding 97 to 85 parts by weight of said fine hollow spherical mixture to 3 to 15 parts by weight of thermosetting resin; adding 0.5 to 80 weight parts in total of fibrous reinforcing agent, coupling agent, inorganic filling agent per 100 weight parts of thermosetting resin and thereafter fully kneading the mixture preliminary moulding said kneaded material into a plate-like article of required dimension for use as a base layer; applying a layer in which thin nonwoven fabric of 50-3001l thickness is impregnated with thermosetting resin with metal powder, pigment, dye and the like precompounded therein dried, on the surface of said base layer;; applying a reverse layer, in which a thin nonwoven fabric of substantially the same thickness as the surface layer is impregnated with thermosetting resin and is dried, on the reverse side of said base layer; and laminating the surface layer, base layer and reverse layer by integral molding at one stage.

17. The method of producing non-flammable light-weight composite material as claimed in Claim 16, wherein a mold with a rugged pattern is used at the time of final molding the surface layer, base layer and reverse layer to form an embossed rugged pattern simultaneously with final molding.

18. A non-flammable light-weight composite material comprising a base layer composed of a compressed and molded kneaded material which is formed by using a fly ash balloon produced using coal as raw material, mixing the fly ash balloon with aluminium hydroxide at the weight ratio of from 20:80 to 60:40 to form a fine hollow spherical mixture, adding 97 to 85 weight parts of said fine hollow spherical mixture to 3 to 15 weight parts of thermosetting resin, and adding 0.5 to 80 weight parts in total of fibrous reinforcing agent, coupling agent, inorganic filling agent and the like to 100 weight parts of thermosetting -resin; a surface layer, in which a thin nonwoven fabric of 50-300Fthick is impregnated with thermosetting resin with metal powder, pigment, dye and the like precompounded and is dried, laminated on the surface of said base layer; and a reverse layer, in which a thin nonwoven fabric of substantially the same thickness as the surface layer is impregnated with thermosetting resin and is dried, laminated on the reverse side of said base layer.

19. The non-flammable light-weight composite material as claimed in Claim 16, wherein a rugged pattern having deep embossed recesses is formed from the surface layer towards the reverse layer.