TECHNICAL FIELD

The present disclosure relates to compositions useful in the production of fire retardant coatings and/or materials, methods of production thereof, and fire retardant coatings and/or materials comprising the same.

BACKGROUND

For fire safety reasons, fire retardant coatings are commonly required by woods and plastics used for household furniture and electric appliances, and by concretes and steels used for constructions and buildings. Woods and plastics are flammable, and the strength of steels and concrete may significantly be weakened at high temperature, which may result in structural damage of buildings made therefrom.

Existing fire retardant coatings may have limitations, such as a narrow operative temperature range (e.g. only applicable at medium to high temperature or only applicable at low temperature), a narrow operative material range (e.g. only applicable on concrete or only applicable on woods and plastics), and environmentally unfriendly. In addition, commonly used fire retardant coatings are either aesthetically appealing yet with poor fire retardancy (e.g. fire retardant paintings), or have good fire retardancy yet aesthetically unattractive (e.g. cement-based fire retardant coatings). Other fire retardants, such as halogenated fire retardants, especially brominated fire retardants, cause serious environmental problems by releasing toxic gases during burning.

On the other hand, the accumulation of solid waste (such as industrial slag, fly ash, desulfurization ash, broken glasses, and mine tailings) on Earth poses serious dangers to public health and contributes to pollution. However, elimination and/or exploitation of solid waste is technically and economically challenging.

Therefore, there is a need for compositions useful in the production of fire retardant coatings that have a wide operative temperature range, a wide operative material range, and are environmentally friendly and aesthetically appealing. There is also a need for methods for preparing such compositions that utilize environmentally hazardous solid wastes and turn the same into fire retardant coatings in a cost-effective manner.

SUMMARY

Provided herein are improved fire retardant compositions that can be readily prepared from solid waste materials and commercially available materials. Also provided herein are fire retardant coatings made from the fire retardant compositions that can have a wide operative temperature range, a wide operative material range, and are environmentally friendly and aesthetically appealing.

In a first aspect of the present disclosure, provided herein is a fire retardant composition comprising at least one non-intumescent composition and at least one intumescent composition, wherein: the at least one non-intumescent composition comprises a curable binder composition, at least one non-intumescent fire retardant ingredient, and at least one reaction enhancing additive; and the at least one intumescent composition comprises a curable binder composition, at least one intumescent fire retardant ingredient, and at least one inorganic filler.

In a first embodiment of the first aspect, the curable binder composition comprises a curing agent and a resin.

In a second embodiment of the first aspect, the curing agent is an aliphatic amine based curing agent with a viscosity of about 5,000-about 15,000 centipoise at 25° C.

In a third embodiment of the first aspect, the resin is a waterborne epoxy resin with a viscosity of about 400-about 750 centipoise at 25° C.

In a fourth embodiment of the first aspect, the at least one non-intumescent fire retardant ingredient is a solid waste material.

In a fifth embodiment of the first aspect, the at least one intumescent fire retardant ingredients are selected from the group consisting of a carbon-source agent, a blowing agent, an acid-source agent, and combinations thereof.

In a sixth embodiment of the first aspect, the at least one inorganic filler is a metal hydroxide with an average particle size of about 10 nm-about 500 nm.

In a seventh embodiment of the first aspect, the fire retardant composition further comprises an anti-weathering composition.

In an eighth embodiment of the first aspect, the non-intumescent composition comprises about 1.6%-about 9.9% by weight curable binder composition, about 0.3%-about 76.0% by weight non-intumescent ingredients, and about 2.0%-about 30.4% by weight reaction enhancing additive; and the intumescent composition comprises about 6.2%-about 26.9% by weight curable binder composition, about 11.8%-about 56.0% by weight intumescent ingredients, and about 0.4%-about 8.8% by weight inorganic filler.

In a ninth embodiment of the first aspect, the inorganic filler has an average particle size of about 10 nm-about 500 nm.

In a tenth embodiment of the first aspect, the non-intumescent composition comprises about 1.6%-about 2.8% by weight curing agent, about 4.1%-about 7.1% by weight resin, about 39.5%-about 65.7% by weight fly ash, about 0.3%-about 10.3% by weight slag, about 2.0%-about 2.8% by weight alkali metal hydroxide, and about 14.4%-about 27.6% by weight alkali metal silicate solution; and the intumescent composition comprises about 6.2%-about 6.6% by weight curing agent, about 15.3%-about 16.7% by weight resin, about 11.8%-about 13.0% by weight carbon-source agent, about 15.8%-about 17.2% by weight blowing agent, about 23.6%-about 25.8% by weight acid-source agent, and about 0.4%-about 8.8% by weight inorganic filler.

In an eleventh embodiment of the first aspect, the inorganic filler has an average particle size of about 10 nm-about 500 nm.

In a twelfth embodiment of the first aspect, the non-intumescent composition comprises about 1.6%-about 2.8% by weight aliphatic amine based curing agent with a viscosity of about 5,000-about 15,000 centipoise at 25° C., about 4.1%-about 7.1% by weight waterborne epoxy resin with a viscosity of about 400-about 750 centipoise at 25° C., about 39.5%-about 65.7% by weight fly ash, about 0.3%-about 10.3% by weight slag, about 2.0%-about 2.8% by weight sodium hydroxide, about 14.4%-about 27.6% by weight sodium silicate solution, and about 1.5%-about 20.3% by weight water; and the intumescent composition comprises about 6.2%-about 6.6% by weight aliphatic amine based curing agent with a viscosity of about 5,000-about 15,000 centipoise at 25° C., about 15.3%-about 16.7% by weight waterborne epoxy resin with a viscosity of about 400-about 750 centipoise at 25° C., about 11.8%-about 13.0% by weight pentaerythritol, about 15.8%-about 17.2% by weight melamine, about 23.6%-about 25.8% by weight ammonium polyphosphate, about 0.4%-about 4.4% by weight magnesium hydroxide, about 0.4%-about 4.4% by weight aluminum hydroxide, and about 5.2%-about 33.2% by weight water.

In a thirteenth embodiment of the first aspect, the magnesium hydroxide has an average particle size of about 110 nm-about 500 nm, and the aluminum hydroxide has an average particle size of about 10 nm-about 500 nm.

In a second aspect of the present disclosure, provided herein is a method of preparing the fire retardant composition of the first aspect, comprising the steps of: a) mixing a curable binder composition, at least one non-intumescent fire retardant ingredient, and at least one reaction enhancing additive thereby forming a non-intumescent composition; and b) mixing a curable binder composition, at least one intumescent fire retardant ingredients, and at least one inorganic fillers thereby forming an intumescent composition.

In a third aspect of the present disclosure, provided herein is a fire retardant coating comprising a first layer 2 and a second layer 3, wherein the first layer 2 is formed by the non-intumescent composition of the first aspect of the present disclosure, and the second layer 3 is formed by the intumescent composition of the first aspect of the present disclosure.

In a first embodiment of the third aspect, the non-intumescent composition comprises about 1.6%-about 2.8% by weight aliphatic amine based curing agent with a viscosity of about 5,000-about 15,000 centipoise at 25° C., about 4.1%-about 7.1% by weight waterborne epoxy resin with a viscosity of about 400-about 750 centipoise at 25° C., about 39.5%-about 65.7% by weight fly ash, about 0.3%-about 10.3% by weight slag, about 2.0%-about 2.8% by weight sodium hydroxide, about 14.4%-about 27.6% by weight sodium silicate solution, and about 1.5%-about 20.3% by weight water; and the intumescent composition comprises about 6.2%-about 6.6% by weight aliphatic amine based curing agent with a viscosity of about 5,000-about 15,000 centipoise at 25° C., about 15.3%-about 16.7% by weight waterborne epoxy resin with a viscosity of about 400-about 750 centipoise at 25° C., about 11.8%-about 13.0% by weight pentaerythritol, about 15.8%-about 17.2% by weight melamine, about 23.6%-about 25.8% by weight ammonium polyphosphate, about 0.4%-about 4.4% by weight magnesium hydroxide, about 0.4%-about 4.4% by weight aluminum hydroxide, and about 5.2%-about 33.2% by weight water.

In a second embodiment of the third aspect, the magnesium hydroxide has an average particle size of about 10 nm-about 500 nm, and the aluminum hydroxide has an average particle size of about 10 nm-about 500 nm.

In a third embodiment of the third aspect, the fire retardant coating further comprises a third layer 4, wherein the third layer 4 is formed by an anti-weathering composition.

In a fourth embodiment of the third aspect, the anti-weathering composition comprises about 4.81%-about 6.81% by weight vinyl silicone oil with a viscosity of about 95,000 centipoise-about 105,000 centipoise, about 86.09%-about 88.09% by weight vinyl silicone oil with a viscosity of about 400 centipoise-about 600 centipoise, about 0.005%-about 0.015% by weight platinum catalyst, about 0.08%-about 0.28% by weight 1-ethynyl-1-cyclohexanol, and about 5.91%-about 7.91% by weight hydrogen silicone oil with a viscosity of about 70 centipoise-about 110 centipoise.

The fire retardant coatings and/or materials of the present disclosure can be applied at a wide range of temperatures and on a wide range of materials (e.g. steel, concrete, wood, and plastic) with good fire retardancy, strong adhesiveness, good scratch resistance, good hardness, and are environmentally friendly (e.g. utilize solid waste materials to reduce environmental burdens and contain very little toxic substances after burning) and aesthetically appealing (e.g. smooth and even surface with adjustable colors). In addition, the fire retardant compositions can be prepared at ambient temperature within a short time, e.g. less than 20 min, and such compositions can be applied onto a variety of substrate materials using conventional methods, such as spray, rolling, brushing, troweling, etc. Moreover, the fire retardant coatings formed by the compositions of the present disclosure can be dried at ambient temperature in a short period of time, e.g. less than 4 hours.

In particular, the fire retardant coatings of the present disclosure can pass BS476 (Standard for Safety of Flammability: fire test on building materials and structures) for steel, concrete and wood substrates and UL 94 (Standard for Safety of Flammability of Plastic Materials for Parts in Devices and Appliances testing) for plastic substrates.

Advantageously, the content of lead (Pb), mercury (Hg), cadmium (Cd), hexavalent chromium (Cr6+), polybrominated biphenyls (PBB), polybrominated diphenyl ether (PBDE), bis(2-ethylhexyl), phthalate (DEHP), butyl benzyl phthalate (BBP), dibutyl phthalate (DBP) and diisobutyl phthalate (DIBP) in the fire retardant coatings of the present disclosure are lower than the limit as set in the Restriction of Hazardous Substances: RoHS Directive (EU) 2015/863 amending Annex II to Directive 2011/65/EU.

In addition, the volatile organic compound (VOC) content of the fire retardant coating of the present disclosure can be as low (8 g/L) and complies with environmental regulation. This shows that the fire retardant coating of the present disclosure is even more environmental-friendly than the existing products.

Tape tests have also been performed to the fire retardant coating of the present disclosure by attempting to remove the coating with tape after the coating is cut with cutting tool, and the test results confirmed that the developed fire retardant coating can have good adhesion (up to 4B) to a broad range of substrates, such as steel, concrete, wood and plastic.

Pencil tests have been performed to the fire retardant coating of the present disclosure by pushing pencils of known hardness over the coating in order to obtain the coating hardness, and the test results confirmed that the developed fire retardant coating can have good hardness, e.g., up to 2H.

Scratch tests have been performed to the fire retardant coating of the present disclosure by scratching the coating with a scratch stylus loaded with a specified load and checking if there is any scratch on the coating surface by naked eyes and/or microscope, and the test results confirmed that the fire retardant coating of the present disclosure can have good scratch resistance, e.g., up to 2H.

In order to improve the application of a fire retardant coating, it should have good rapid drying. Drying tests have been performed on the fire retardant coatings described herein, e.g. by touching the surface after drying less than 4 hours and checking if there is any imprint on the coating surface by naked eye and/or microscope. The test results confirmed that the retardant coatings described herein have good rapid drying.

