JPS6134079A - Sprayable fire-proof coating - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to novel compositions useful as sprayable fire retardant coatings containing at least one hydroxypropyl hydroxyethyl cellulose.

In the building and construction industry, fire-retardant coatings are applied by spraying to structural parts of buildings, especially girder 1 structural columns, and to metal facing parts of buildings for the dissipation of heat in case of fire. often applied.

Traditional sprayable fire retardant coatings are calcined gypsum (p
(Laster of Paris) or a mixture of hydraulic cements, such as Portland cement, amounts of mineral wool and vermiculite, and small proportions of thickeners for rheology adjustment and water retention. Such mixtures may also contain perlite as a heat spreader. The dry gypsum or cement mixture is simply mixed with water using specialized mixing equipment and applied by pressurized spraying to the surface of the appropriate structural part of the building.

Plaster of Paris is a natural gypsum, and its chemical formula is CaSO4
@2H20, which is converted to calcium sulfate hemihydrate by known methods. Commercially available calcined gypsum varies greatly in quality, purity and properties, depending on where it is mined and how it is manufactured.

A wide variety of hydraulic cements that can be used in the present invention are known and commercially available. All types of Portland cement are particularly useful. Other hydraulic cements can be used, such as persulfated slag cements, calcium aluminate cements, natural cements, pozzolanic cements and lime.

The physical properties of cured conventional sprayable fire retardant coatings are influenced by the rate of cure and thus by the rate of water removal during the curing operation. Influences acting on these parameters at the onset of the curing reaction, either by increasing the rate of water removal or by decreasing the water concentration in the sprayable fire-retardant coating, degrade the physical properties of the fire-retardant coating.

To overcome, or at least minimize, the aforementioned water loss problems, small amounts of water-soluble polymers, such as starch, hydroxyethyl cellulose and hydroxypropyl cellulose, are used as water retention aids in sprayable fire retardant It has been added to coating compositions. Preferably.

These polymers first create high water absorption of the fire retardant coating composition and then increase the viscosity of the aqueous phase of the fire retardant coating composition, thus maintaining the desired water concentration in the coating composition during curing. This prevents water from separating from the fire retardant coating composition. Furthermore, these polymers are intended to impart a high air content to the sprayable fire-retardant coating, thereby allowing it to be pumped easily and smoothly at low pressures. However, the aforementioned water-soluble polymers often fail to provide and retain the desired water concentration and air content in sprayable fire-retardant coatings, are thus difficult to pump, and exhibit relatively poor spray properties, e.g. and provide a sprayable fire retardant coating with inadequate cure strength. Another disadvantage of sprayable fire retardant coatings is that after application to the structural support, the application becomes uneven due to sagging of the sprayable fire retardant coating.

According to the invention, calcined gypsum or hydraulic cement; mineral wool; vermiculite; and preferably from about 0,05 parts to about 1;
of water-retaining thickener, about 19 parts of its own weight
In a dry sprayable fire retardant coating composition that, when mixed with 0 parts to about 210 parts of water, can produce a fire retardant coating composition that can be sprayed in a thin layer onto the surface of a structural support, As a water retentive thickening agent, at least one hydroxypropyl hydroxyethyl cellulose is used, said hydroxypropyl hydroxyethyl cellulose contains about 0.3 to 9734.0 hydroxyethyl M, S, and 0. Hydroxypropyl M, S greater than 35.

A dry sprayable fire retardant coating composition is provided having the following characteristics: When a dry sprayable fire retardant coating is based on calcined gypsum, it may also be referred to herein as a dry gypsum composition. When a dry sprayable fire retardant coating is based on hydraulic cement, it may also be referred to herein as a dry cement composition.

Preferably, the dry gypsum compositions of the present invention have a dry gypsum composition of about 15 to about 35
1 part calcined gypsum, about 15 to about 35 parts mineral wool, about 40 to about 70 parts vermiculite, and about 0.05 to about 1 part of at least one hydroxypropyl hydroxyethylcellulose, the sum of which is 100 copies. Most preferably, the dry gypsum mixture includes about 20 to about 30 parts of plaster of paris, about 20 to about 30 parts of mineral wool, about 45 to about 55 parts of vermiculite, and about 0.1 to about 0.2 parts. of at least one hydroxypropyl hydroxyethylcellulose, the total amount of which is 100 parts.

Preferably, the dry cement compositions of the present invention contain, on the other hand, about 40 to about 60 parts of hydraulic cement, about 20 to about 3
0 parts mineral wool, about 20 to about 50 parts vermiculite, and about 0 parts
．． 0.5 to about 1 part of at least one hydroxypropyl hydroxyethyl cellulose, totaling 100 parts. Most preferably, the dry cement mixture is about 45 to about 55 parts hydraulic cement, about 15 to about 25 parts.
about 25 to about 35 parts mineral wool, about 25 to about 35 parts vermiculite, and about 0.
1 to about 0.2 parts of at least one hydroxypropyl hydroxyethylcellulose, for a total of 100 parts.

Preferably, the hydroxypropyl hydroxyethylcellulose has at least 0.6 hydroxypropyl M, S
, most preferably it has about 0.7-1.5
Hydroxyethyl M.

S, and about 0.6 to about 1.2 hydroxypropyl M
, S. The total M, S of these two types of substituents
, has a high Brookfield viscosity, i.e., a 1% solution T of at least 100 centipoise (c
ps), preferably from 2000 to about 4000 cps. In general, these two
The sum of the species substituents, M, S, is from about 1.0 to about 5.0.

i M, s refers to the average number of moles of hydroxyethyl or hydroxypropyl substituents attached per anhydroglucose unit of cellulose.

For example, when compared to a sprayable fire retardant coating prepared using the most commonly used thickener in sprayable fire retardant coatings, namely methyl hydroxypropyl cellulose, the sprayable fire retardant coatings of the present invention Fire retardant coatings exhibit improved sprayability, sag resistance, water absorption and water retention, which are parameters widely used in the field to characterize sprayable fire retardant coatings.

The fire retardant coating of the present invention exhibits improved air entrainment when it is based on plaster of Paris.

Hydroxypropyl hydroxyethyl cellulose, which can be used as a thickener, water retention aid in the sprayable fire-retardant coatings of the present invention, is prepared by reacting ethylene oxide and propylene oxide with cellulose in a strongly alkaline medium. Specific techniques for carrying out this etherification are known in the art, and any known procedure can be used.

In another method, hydroxyethylcellulose can be etherified with propylene oxide in a strongly alkaline medium. In this case, the hydroxyethylcellulose has an M, S of substantially from about 0.3 to about 4.0.
, can be of any grade with . Preferred materials are from about 100 to about 5000 in a 1% solution at 23°C.
It has a Brookfield viscosity of c p s.

However, materials with higher and lower viscosities can be used to advantage.

Regardless of the method of preparing hydroxyprobyl hydroxyethylcellulose, the product is neutralized with an acid, preferably nitric acid or a mixture of acids, for example a mixture of nitric acid and acetic acid, and then with about -9.0% acetone. Washing with an aqueous solution of acetone removes reaction by-products, such as alkali metal salts, ethylene glycol, and propylene glycol, so that the final purified product has an ash content of about 5% or less. Preferably, the product has an ash content of about 2.9 to 4.9.

Hydroxyethylcellulose can be prepared using any cellulose feed, such as wood pulp, cotton linters of varying viscosities, and the like.

Air entraining agents, such as sodium lauryl sulfate or sodium stearate, in an amount of 0.001 of the weight of the dry composition.
It can also be added in amounts of up to about 1.0 part, with the amounts of other ingredients of the dry composition being adjusted such that the total amount is 100 parts.

A thermodiffusible component, such as perlite, can also be added in an amount of 25 to about 60 parts by weight of the dry composition, with the amounts of other components of the dry composition being adjusted such that the total amount is 100 parts. be done.

The sprayable fire retardant coating is prepared by adding water to a dry composition containing (1) calcined gypsum or hydraulic cement, (2) mineral wool, (3) vermiculite, and (4) the thickening agent of the present invention. It can be prepared by adding The proportion of thickener in the dry plaster of Paris or cement typically ranges from about 0.05 to about 1 part, preferably from about 0.1 to about 0.5 parts by weight of the composition. Plaster of Paris or cement acts as a hydraulic adhesive for the coating composition.

These dry gypsum compositions or hydraulic cement compositions are
When water is added, 0.64 to about 5
．． 08 cm (1/4 to 2 inches), typically 1.27
- Forms a blowable plaster or cement in a layer of about 1/2 to 1 inch (2.54 cm). The amount of water used is such that the resulting stone chip or cement composition is sprayable and not so dilute that it slides or falls off the surface of the support when applied. Generally, from about 190 parts to 210 parts, based on the weight of the dry composition.
Part of the water gives excellent results.

Example 11 - This example illustrates a preferred embodiment of the sprayable fire retardant coating composition of the present invention and its method of preparation.

(a) 25% plaster of Paris, (b) tumble blended
99.65 parts of a mixture with 25% mineral wool and (c) 50% vermiculite; and hydroxypropyl with 1.0 hydroxypropyl M,S and 1°2 hydroxyethyl M,S 0.35 parts of hydroxyethylcellulose is provided and tumble blended at room temperature (approximately 23°C) to a substantially homogeneous state. This dry mixture is added to water at the workplace in a ratio of 1:2 (two bottles of dry mixture) in a specialized mixing device, and this wet mixture is immediately pumped and passed by a machine through a spray nozzle onto the surface of the structure. ” Shout out to Ni.

This example illustrates another specific embodiment of the sprayable fire retardant coating composition of the present invention.

A blowable fire retardant coating is prepared according to the procedure and formulation of Example 1, except that 1.0 hydroxypropyl M,S and 1.2 hydroxyethyl M,S,
Instead of hydroxypropyl hydroxyethylcellulose with 0.9 hydroxypropyl M,S and 0.9 human lnia*diethyl M,S, hydroxypropylhydroxyethylcellulose is used.

- Application - This example illustrates another specific embodiment of the sprayable fire retardant coating composition of the present invention.

A sprayable fire retardant coating is prepared according to the procedure and formulation of Example 1, except that 1.0 hydroxypropyl M,S and 1.2 hydroxyethyl M,S,
Instead of hydroxypropyl hydroxyethyl cellulose with 0.98 hydroxypropyl M, S and 1.23 hydroxyethyl M, i, hydroxypropyl hydroxyethyl cellulose is used.

Kazumi] Ie A - This example illustrates another specific embodiment of the sprayable fire retardant coating composition of the present invention.

A sprayable fire-retardant coating was prepared according to the procedure and formulation of Example 1 in a mixture having (a) 50% Portland Cement White Type 1, (b) 20% mineral wool, and (c) 30% vermiculite. 99.65 parts of; and 1.0 hydroxypropyl M, S, and 1.2 hydroxyethyl M.

Prepared using 0.35 parts of hydroxypropyl hydroxyethyl cellulose with S.

Example 1 - This example illustrates another specific embodiment of the sprayable fire retardant coating composition of the present invention.

A sprayable fire retardant coating is prepared according to the procedure and formulation of Example 1, except using 99.5 parts of the mixture instead of 99.65 parts and 0.5 parts of hydroxy instead of 0.35 parts. Use propyl hydroxyethylcellulose.

Properties of hydroxypropyl hydroxyethyl cellulose in sprayable fire retardant coatings.

It was evaluated using the following test method.

Water loss (or water retention) is a measure of the amount of bleed or water loss that a composition experiences when it comes into contact with an absorbent surface. Low water loss rate values are desirable because excessive water loss reduces strength and causes the dried fire retardant coating composition to crack.

9.0 cm No. 1 of 40 Whatman filter paper
Stitch 0 circular objects (circle) with a stable
Determine the amount of water loss by tapping) and weighing. The stack of filter papers is then placed on a flat surface and covered with a piece of 11, Ocm No. 4 Whatman filter paper. Diameter 5.1cm (2 inches) x length 7
．． Place a 6 cm (3 inch) cylinder on top of this stack of filter paper. Fill this cylinder to the top with a mixture of wet plaster or cement. After 1 minute of precision, remove the cylinder and 1 sheet of paper, 4 copies. The stack of filter papers is weighed to determine the water gain, which is expressed as water loss (g) from the gypsum or cement based fire retardant coating composition.

The amount of air entrained in the composition is determined gravimetrically.

The wet fire retardant coating mixture is placed into a cylinder of known volume and tapped to remove large air bubbles. Drain the mixture at the top of the cylinder to obtain a known volume of mixture. Measure the weight of this mixture. The specific gravity of the wet mixture and the known specific gravity of the solids in this mixture.

and calculate the air volume of the wet mixture. The high air content in fire-retardant coating compositions causes pump transport (pump
p) is desirable because it leads to a coating mixture that is easy to use.

Sag resistance and spray characteristics are primarily determined.

The properties of the sprayable fire-retardant coatings prepared using the hydroxypropyl hydroxyethyl cellulose of Examples 1-4 are compared with three control sprayable fire-retardant coatings using prior art thickeners and the table below: A comparison is shown below. Control A is prepared according to the recipe and procedure of Example 1, except that 0.35 parts of methylhydroxypropyl cellulose having methyl D,S of about 0.15 and hydroxyethyl M,S of about 1.8. use. Control B is prepared according to the procedure of Example 1 and using the formulation of Example 4, except that methylhydroxypropyl has a methyl D, S of about 0.15 and a hydroxyethyl M, S of about 1.8. Use 0.35 parts of cellulose.

Control C is prepared according to the procedure and formulation of Example 1, but
0.5 parts of methylhydroxypropylcellulose, except that 99.5 parts of the mixture is used instead of 99.65 parts, and 0.5 parts of methyl hydroxypropyl cellulose having about 0.15 methyl D, S, and about 1°8 hydroxyethyl M, S. ．． use the section.

The degree of substitution (D, S,) is the average number of methyl groups per anhydroglucose unit of cellulose.

As used herein, the term "consisting essentially of" excludes any unlisted substance in sufficient concentration to substantially adversely affect the essential properties and characteristics of the defined composition, but , permitting the presence of one or more unlisted substances in insufficient concentrations to substantially adversely affect said essential properties and characteristics.

Features, advantages and other specific embodiments of the invention will be readily apparent to those skilled in the art after reading the above disclosure; in this regard, specific embodiments of the invention have been described in considerable detail. However, changes and modifications to these embodiments are possible without departing from the spirit and scope of the invention as disclosed and claimed.

Claims (1)

[Claims] 1. Contains calcined gypsum or hydraulic cement; mineral wool; vermiculite; and a water-retaining thickener, about 19% of its own weight.
In a dry sprayable fire retardant coating composition that, when mixed with 0 parts to about 210 parts of water, can produce a fire retardant coating composition that can be sprayed in a thin layer onto the surface of a structural support, consisting essentially of using at least one hydroxypropyl hydroxyethylcellulose as a water-retaining thickener, said hydroxypropylhydroxyethylcellulose having a hydroxyethyl M.O. of about 0.3 to about 4.0. S. and hydroxypropyl M. S. 1. A dry sprayable fire retardant coating composition comprising: 2. The hydroxypropyl hydroxyethylcellulose has at least 0.6 hydroxypropyl M. S. The composition according to claim 1, having the following. 3. The hydroxypropyl hydroxyethylcellulose has a hydroxyethyl M.D. of about 0.7 to about 1.8. S. and about 0.6 to about 1.2 hydroxypropyl M. S.
The composition according to claim 1, having the following. 4. The composition of claim 1, wherein said hydroxypropyl hydroxyethyl cellulose is present in an amount of about 0.1 part to about 0.5 part.