WO2024065360A1

WO2024065360A1 - Tiling adhesive with improved flexibilty

Info

Publication number: WO2024065360A1
Application number: PCT/CN2022/122457
Authority: WO
Inventors: Jian Li; Kunpeng GUO; Shaoguang Feng; Xiang GENG
Original assignee: Dow Global Technologies Llc
Priority date: 2022-09-29
Filing date: 2022-09-29
Publication date: 2024-04-04

Abstract

In mortars used for tile adhesion, flexibility can be improved by incorporating in the mortar from 3 to 15 weight percent of recycled composite fibers that have an average diameter of no more than 50 microns and an average length of no more than 800 micron. In some cases, the dry components can be pre-mixed as a dry mix before blending in water to make the mortar.

Description

IMPROVED TILING ADHESIVE

FIELD

This invention relates to the field of cement-based tile adhesives.

INTRODUCTION

Tiled surfaces typically comprise: (a) a substrate such as a wall or floor, (b) tiles and (c) an adhesive that binds the tiles to the substrate.

In many cases, the adhesive is a cement-based tile adhesive, which is often called a mortar. Mortars that are used for tiling frequently comprise the following dry components, mixed with water: (a) a hydraulic binder (also called a “cement” ) , such as Portland cement; (b) an inorganic filler, such as sand; and (c) a water-dispersible organic binder. Some mortars contain further components, such as cellulose ethers, starch ethers, inorganic rheology modifiers, inorganic or organic fibers, air-entraining agents, accelerators, retarders, superplasticizers and defoamers.

The fillers used in mortars have different particle sizes depending on intended use. See, for example, “Dry Mortar” , Ullmann’s Encyclopedia of Industrial Chemistry (7 ^th Ed. ) at P 557. The filler used in tiling mortar often has a maximum particle size between 0.5 mm and 1 mm, while bricklaying mortars may have somewhat larger particles and finishing plasters may have smaller particles. In contrast, structural concrete usually contains larger particle sizes such as 5 mm to 10 mm.

Mortars are governed by national and international performance standards, such as industrial standard JC/T 547-2017 in China, standard EN 12004 in Europe and ISO 13007 globally. For some applications, a flexible mortar is desirable. Flexible mortars give the tiled surface more durability and less brittleness under stress or temperature cycles. The standards require that a “deformable adhesive” must be capable of transverse deformation of at least 2.5 mm under test conditions. See for example, in European Standard EN 12004.

It is desirable to find additives that can improve the flexibility of mortar while retaining other desirable properties such as adequate tensile adhesion.

SUMMARY

We have discovered that an appropriate amount of recycled composite fibers added to mortar can improve the flexibility of the mortar while retaining adequate tensile adhesion. This result is unexpected, because components in the recycled composites, such as fibers and matrix resins, are ordinarily selected to have high stiffness and low flexibility.

One aspect of the present invention is a dry mix composition comprising:

a) cement;

b) an inorganic filler wherein 95 to 100 weight percent of filler particles will pass through a sieve of 2.36 mm;

c) an organic binder suitable for use in tiling mortar;

d) from 3 to 15 weight percent of recycled composite fibers that have an average diameter of no more than 50 micron and an average length of no more than 800 micron.

wherein all weight percentages are based on the weight of the dry components (a) - (d) .

A second aspect of the present invention is a mortar comprising:

a) cement;

c) an organic binder suitable for use in tiling mortar;

d) from 3 to 15 weight percent of recycled composite fibers that have an average diameter of no more than 50 micron and an average length of no more than 800 micron, and

e) water

wherein all weight percentages are based on the weight of the dry components (a) - (d) , excluding the water.

A third aspect of the present invention is a process to use the mortar in the second aspect to affix tiles to a substrate, comprising the steps of:

a) applying the mortar to a substrate;

b) applying a plurality of tiles to the mortar on the substrate; and

c) permitting the mortar to set.

A fourth aspect of the present invention is a tiled surface comprising:

1. a substrate;

2. a plurality of tiles; and

3. a set mortar adhering the tiles to the substrate, wherein the mortar contains: (a) cement, (b) an inorganic filler, (c) an organic binder suitable for use in tiling mortar; and (d) from 3 to 15 weight percent of recycled composite fibers that have an average diameter of no more than 50 micron and an average length of no more than 800 micron, wherein all weight percentages are based on the weight of components (a) - (d) .

The invention provides a useful outlet for short fibers recycled from composites. There is a need to economically recycle end-of-life composite parts, such as wind turbine blades and auto, boat and airplane parts. Short-ground fibers are easy to make, but usually have low value because they replace inexpensive fillers. The present invention allows the less-expensive short-ground fibers to add value beyond simple filler value.

DETAILED DESCRIPTION

Mortars and dry mixes of this invention contain (a) cement, (b) an inorganic filler, (c) an organic binder suitable for use in tiling mortar; (d) from 3 to 15 weight percent of recycled composite fibers that have an average diameter of no more than 50 micron and an average length of no more than 800 micron, wherein all weight percentages are based on the weight of components (a) - (d) . The mortars further contain (e) water.

In some embodiments, the mortar is made by first making the dry mix and then blending water into the dry mix. In some embodiments, the mortar is made by first blending one or more components of the mortar with water, and later blending the remaining components of the mortar to the water-borne mixture, separately or together. Both embodiments can make the same mortar, but the first embodiment makes and uses the dry mix of the present invention, and the second embodiment does not. In both the mortar and dry mix, the selection and relative proportions of the components, other than water, are the same.

The dry mix/mortar contains cement. The ASTM recognizes five categories of cement: Type 1 (ordinary Portland cement) ; Type 2 (moderate sulfate resistant cement) ; Type 3 (rapid hardening cement) , Type 4 (low heat cement) and Type 5 (high sulfate resistant cement) . Any of these cements may be used in the dry mix/mortar. In some embodiments, the cement is ordinary Portland cement. In some embodiments, the cement is a variation of ordinary Portland cement, known as white cement. In some embodiments, the cement is a more specialized cement, such as a high alumina cement or a calcium sulfoaluminate cement. Suitable cements are commercially available.

The dry mix/mortar should contain enough cement to be effective as a tile adhesive. In some embodiments, the dry mix/mortar contains at least 15 weight percent cement or at least 20 weight percent or at least 22 weight percent or at least 25 weight percent or at least 30 weight percent or at least 35 weight percent, based on the dry components and excluding water. In some embodiments, the dry mix/mortar contains at most 60 weight percent cement or at most 55 weight percent or at most 50 weight percent or at most 45 weight percent, based on the dry components and excluding water.

The dry mix/mortar contains inorganic filler, for which 95 to 100 weight percent of the filler will pass through a 2.36 mm (Mesh 8) sieve. Examples of inorganic fillers include silica sand, quartz sand, kaolin, calcium carbonate, magnesium carbonate, talc or mixture thereof. Suitable inorganic fillers are commercially available.

In some embodiments, 95 percent to 100 percent of the inorganic filler has a particle size of no more than 1.5 mm or 1.2 mm or 1.0 mm or 0.8 mm or 0.7 mm or 0.6 mm. In some embodiments, the inorganic filler contains at least 5 percent particles with a size of at least 0.1 mm or at least 0.2 mm or at least 0.3 mm.

In some embodiments, the dry mix/mortar contains at least 20 weight percent of inorganic filler or at least 24 weight percent or at least 30 weight percent or at least 40 weight percent or at least 45 weight percent or at least 50 weight percent, based on the dry components and excluding water. In some embodiments, the dry mix/mortar contains at most 80 weight percent of inorganic filler or at most 70 weight percent or at most 65 weight percent or at most 60 weight percent or at most 55 weight percent, based on the dry components and excluding water.

The dry mix/mortar contains an organic binder that is suitable for use in tiling mortar. In some embodiments, the organic binder is water-dispersible. In some embodiments, the organic binder is a dry powder before the components are mixed with water, called a “redispersible powder” . The redispersible powder contains an organic polymer and optionally a surfactant that can form a stable polymer emulsion when mixed with water. In some embodiments, the redispersible powder is made by (1) forming a polymer emulsion containing the organic polymer and the surfactant (if any) and (2) drying the emulsion to form the powder such as by spray drying. In such case, the redispersible powder may contain both the organic polymer and the surfactant that were present in the emulsion. In some embodiments, redispersible powders may sometimes further contain additives such as anti-caking agents. Calcium carbonate and kaolin are examples of common anticaking agents.

In some embodiments, the organic binder contains an acrylic copolymer, vinyl ester copolymer or styrene-butadiene (SB) copolymer.

In some embodiments, the organic binder contains a vinyl ester copolymer. Examples of suitable vinyl ester copolymers are described in US Patent 6, 890, 975. In some embodiments, the vinyl ester copolymer is a vinyl acetate-ethylene (VAE) copolymer. In some embodiments, the vinyl ester copolymer is a vinyl ester of versatic acid (VEOVA) copolymer.

Vinyl ester copolymers contain repeating units derived from one or more vinyl ester monomers, such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl 2-ethylhexanoate, vinyl laurate, 1-methylvinyl acetate, vinyl pivalate, and vinyl esters of C-branched monocarboxylic acids having 9 to 11 carbon atoms, such as vinyl versatate. In some embodiments, the vinyl ester copolymer comprises vinyl acetate. In some embodiments, the vinyl ester copolymer comprises both vinyl acetate and vinyl esters of C-branched monocarboxylic acids having 9 to 11 carbon atoms; examples of such polymers are commercially available under the trademark VeoVa.

In some embodiments, the vinyl ester copolymer further comprises repeating units derived from ethylene or vinyl chloride. For example, vinyl ester-ethylene copolymers may contain at least 1 weight percent repeating units derived from ethylene or at least 5 weight percent or at least 10 weight percent, and vinyl ester-ethylene copolymers may contain at most 60 weight percent repeating units derived from ethylene or at most 50 weight percent.

In some embodiments, the vinyl ester copolymer further comprises repeating units derived from an acrylic or methacrylic ester such as n-butyl acrylate or 2-ethyl hexyl acrylate. For example, vinyl ester-acrylic ester copolymers may contain 30 to 90 weight percent repeating units derived from vinyl ester, 1 to 60 weight percent repeating units derived from acrylic ester and 1 to 40 weight percent repeating units derived from ethylene. In some embodiments, the vinyl ester copolymer comprises no measurable quantity of acrylic or methacrylic ester.

Vinyl ester copolymers may further contain a small quantity of repeating units derived from ethylenically unsaturated monocarboxylic acids or dicarboxylic acids or their anhydrides, ethylenically unsaturated carboxamides or carbonitriles, ethylenically unsaturated sulfonic acids and their salts and vinyl silanes. Examples of common comonomers in this group include ethylene, acrylic acid, methacrylic acid, acrylamide, acrylonitrile, vinyl trimethoxysilane, vinyl triethoxysilane, vinyl tripropoxysilane, vinyl triisopropoxysilane, and sodium vinyl sulfonate. In some embodiments, the vinyl ester copolymer contains 0 to 2 weight percent of repeating units derived from such comonomers, or 0 to 1 weight percent or 0.5 to 1 weight percent.

In some embodiments, the organic binder contains an acrylic copolymer. Examples of acrylic polymers include styrene acrylic copolymers such as styrene acrylonitrile copolymers.

In some embodiments, the organic binder has a weight average molecular weight (Mw) of at least 300,000 Da or at least 350,000 Da or at least 400,000 Da. In some embodiments, the water-dispersible organic binder has a weight average molecular weight (Mw) of at most 2,000,000 Da or at most 1, 500,000 Da or at most 1, 200,000 Da.

In some embodiments, the organic binder has a glass-transition temperature of at least -30℃ or at least -20℃ or at least -10℃ or at least 5℃ or at least 15℃. In some embodiments, the water-dispersible organic binder has a glass-transition temperature of at most 40℃ or at most 30℃ or at most 25℃.

In many embodiments, the organic binder further comprises a surfactant. In some embodiments, the surfactant is an anionic surfactant. Examples of nonionic surfactants include nonylphenol ethoxylates and fatty (C ₆ to C ₃₀) alcohol ethoxylates, such as TERGITOL ^TM 15-S-40 and TERGITOL ^TM NP10, which are commercially available from The Dow Chemical Company.

In some embodiments the surfactant is poly-vinyl alcohol (PVOH) . PVOH is a polyvinyl acetate in which acetate groups have been hydrolyzed to alcohol groups. In some embodiments, the PVOH is at least 70%hydrolyzed or at least 80%hydrolyzed or at least 85%hydrolyzed or at least 87%hydrolyzed. In some embodiments, the PVOH is at most 95%hydrolyzed or at most 90%hydrolyzed or at most 88%hydrolyzed. Examples of suitable PVOH have a weight average molecular weight (Mw) of at least 15,000 Da or at least 20,000 Da. Examples of suitable PVOH have a weight average molecular weight (Mw) of at most 150,000 Da or at most 120,000 Da. Examples of suitable PVOH include PVOH 04-88 and PVOH 26-88, which are commercially available.

In some embodiments, the organic binder and surfactant are selected such that the organic binder forms an emulsion with a particle size of at least 200 nm or at least 400 nm or at least 500 nm or at least 600 nm. In some embodiments, the organic binder and surfactant are selected such that the organic binder forms an emulsion with a particle size of at most 1000 nm or most 800 nm.

In some embodiments, the organic binder and surfactant are selected such that the organic binder forms an emulsion which is stable in a cementitious environment. The cement used in mortars creates an alkaline environment that is high in calcium ions. This environment can cause some emulsions to break down. Other combinations of organic binder and surfactant are known to form stable emulsions in this environment, and the combinations that form stable emulsions may be advantageously used in dry mixes/mortars of the present invention.

It will be recognized that nominally dry powders may contain a small amount of moisture. In some embodiments, the water-dispersible organic binder contains no more than 5 weight percent moisture or no more than 4 weight percent or no more than 3 weight percent or no more than 2 weight percent or no more than 1 weight percent, based on the weight of the water-dispersible organic binder. In some embodiments, the water dispersible organic binder may contain no detectable moisture content (0 weight percent, based on the weight of the water-dispersible organic binder) .

Examples of suitable organic binders are commercially available, such as under the DOW ^TM Latex Powder 2000 and DOW ^TM Latex Powder 2001 trademarks and under the VaVeova and VaE-Veova trademarks. Other organic binders can be made in aqueous dispersion by emulsion copolymerization of vinyl ester monomers and ethylene monomer according to known processes, such as are described in Lindemann, Vinyl Acetate/Ethylene Emulsion Copolymers, Paint Manufacture, September 1968, at 30-36, and US Patent 5, 576, 384 and US Application 2009/0069495 A1. The resulting dispersion can be spray-dried to produce a redispersible powder.

In some embodiments, the quantity of organic binder in the dry mix/mortar is at least 0.5 weight percent or at least 1 weight percent or at least 1.5 weight percent or at least 2 weight percent, based on the weight of dry components and excluding water. In some embodiments, the quantity of organic binder in the dry mix/mortar is at most 12 weight percent or at most 10 weight percent or at most 8 weight percent or at most 6 weight percent or at most 5 weight percent, based on the weight of dry components and excluding water.

Dry mixes/mortars of the present invention contain recycled composite fibers that have an average diameter of no more than 50 micron and an average length of no more than 800 micron. Recycled composite fibers can be made by grinding and/or crushing unwanted composites, such as end-of-life wind turbine blades, parts for automobiles, watercraft and aircraft and sporting equipment, and scrap from composites manufacturing. Processes to recover the recycled composite fibers from composites are described in US Patent 5, 569, 424 and US Patent Application 2011/0301287 and Section 4.1 "Mechanical Recycling" in Krauklis et al., Composite Material Recycling Technology –State-of-the-Art and Sustainable Development for the 2020s” , 2021 (5) J. Compos. Sci. 28. ( https: //doi. org/10.3390/jcs5010028) .

The content of the recycled composite fibers reflects the content of the composites they are made from. The composites typically contain fibers embedded in a polymer matrix.

Examples of suitable fibers in the composite include glass fibers, carbon fibers, basalt fibers and aramid fibers. All of the fibers are commercially available. Glass fibers are commonly categorized as E-glass, S-glass or R-glass. E-glass fibers contain borosilicate glass. S-glass fibers contain magnesium aluminosilicate glass. R-glass fibers contain calcium aluminosilicate glass. Examples of other potential glass fibers are sold under the trademarks: ECRGLAS, Advantex and WindStrand.

In some embodiments, the fibers in the composite are all one type of fiber, such as glass fibers, carbon fibers, basalt fibers or aramid fibers. In some embodiments, the fibers in the composite contain a mix of fibers, such as glass and aramid or glass and carbon. In some embodiments, the fibers in the composite contain at least 50 weight percent glass fibers or at least 60 weight percent or at least 70 weight percent or at least 80 weight percent or at least 90 weight percent. In some embodiments, the fibers in the composite contain glass fibers with at least 10 weight percent carbon or aramid fiber, or at least 20 weight percent or at least 30 weight percent. In some embodiments, the fibers in the composite contain glass fibers with no more than 50 weight percent carbon or aramid fiber, or no more than 40 weight percent or no more than 30 weight percent.

In some embodiments, the fibers in the composite are coated with a sizing. Sizing protects the fiber and promotes adhesion to the matrix polymer. Appropriate sizings depend on the fiber selected; they are commercially available and well-known in the composite industry. Examples of suitable sizing for glass and basalt fibers include chromium oxides, titanium oxides and organosilane compounds having amine or epoxy functionality. Examples of sizings for carbon fiber include epoxy, polyamide, polypropylene, or polyurethane dispersions. Examples of sizings for aramid fiber include polyvinyl alcohol and certain other polymers.

Examples of suitable polymer matrices in the composite include both thermoset and thermoplastic polymers. Examples of suitable thermoset resins include epoxy and polyester resins. Examples of suitable thermoplastic polymers include thermoplastic polyurethane, nylon polyamide, high-density polyethylene, low-density polyethylene, polystyrene and polypropylene. In some embodiments, the polymer matrix is a thermoset polymer. In some embodiments, the polymer matrix is an epoxy resin.

Examples of suitable composites include composites that contain glass fibers, and optionally carbon or aramid fibers, embedded in an epoxy matrix. Other examples of suitable composites include composites that contain glass fibers, and optionally carbon or aramid fibers, embedded in a polyester matrix.

The recycled composite fibers contain fibers with adhered matrix resins that reflect the options discussed above. In some embodiments, the recycled composite fibers contain at least 10 weight percent matrix resin or at least 15 weight percent or at least 25 weight percent or at least 30 weight percent, based on the total weight of the recycled composite fibers. In some embodiments, the recycled composite fibers contain at most 50 weight percent matrix resin or at most 45 weight percent or at most 40 weight percent or at most 35 weight percent, based on the total weight of the recycled composite fibers.

The recycled composite fibers average no more than 800 micron in length. In some embodiments, the recycled composite fibers average at least 100 micron in length, or at least 200 micron or at least 250 micron or at least 300 micron. In some embodiments, the recycled composite fibers average at most 700 micron in length, or at most 600 micron or at most 550 micron or at most 500 micron.

The recycled composite fibers average no more than 50 micron in diameter. In some embodiments, the recycled composite fibers average at least 5 micron in diameter, or at least 10 micron or at least 15 micron or at least 20 micron. In some embodiments, the recycled composite fibers average at most 45 micron in diameter, or at most 40 micron or at most 35 micron or at most 30 micron.

In some embodiments, the aspect ratio of the recycled composite fibers (average length/average diameter) is at least 2 or 3 or 4 or 5 or 6 or 7 or 8. In some embodiments, the aspect ratio of the recycled composite fibers is at most 100 or 50 or 30 or 20 or 18 or 15 or 12 or 10.

The dry mix/mortar contains from 3 to 15 weight percent recycled composite fibers, based on the weight of dry components, excluding water. In some embodiments, the dry mix/mortar contains at least 4 weight percent recycled composite fibers, based on the weight of dry components, excluding water, or at least 5 weight percent or at least 6 weight percent or at least 7 weight percent. In some embodiments, the dry mix/mortar contains at most 12 weight percent recycled composite fibers, based on the weight of dry components, excluding water, or at most 10 weight percent.

Some embodiments of the dry mix/mortar further contain pozzolans such as fly ash, calcined kaolin, pumices, or fumed silica. In some embodiments, the dry mix/mortar contains at least 5 weight percent pozzolans, or at least 10 weight percent or at least 15 weight percent, based on the weight of dry components and excluding water. In some embodiments, the dry mix/mortar contains at most 50 weight percent pozzolans, or at most 40 weight percent or at most 30 weight percent, based on the weight of dry components and excluding water. Pozzolans and their use in mortars and concrete are well-known and described in US Patent 9181131B2

In addition to cement and filler, some embodiments of the dry mix/mortar may optionally contain other additives, such as cellulose ethers, starch ethers, inorganic rheology modifiers, air-entraining agents, accelerators, retarders, superplasticizers and defoamers.

· Cellulose ethers, such as methyl cellulose, ethyl cellulose and methyl ethyl cellulose, can increase the water retention of the mortar and lengthen open time. Cellulose ethers can also improve the workability and viscosity of the mortar. Appropriate cellulose ethers are commercially available, such as under the WALOCEL ^TM OR METHOCEL ^TM trademark.

· Starch ethers, such as hydroxypropyl starch ether, can improve the anti-sagging and anti-slip performance of the mortar, as well as lengthening open time and providing a smoother surface. Appropriate starch-ethers are commercially available, such as under the Aqualon trademark.

· Inorganic rheology modifiers, such as bentonite clay, organically-modified clay, attapulgite, fumed silica and precipitated calcium carbonate, can modify the viscosity and shear thinning behavior of the mortar. Suitable inorganic rheology modifiers with instructions for their use are commercially available.

· Air-entraining agents cause the formation of small air-bubbles in the mortar, which can improve its resilience under freeze-thaw cycles. Air-entrainment agents are frequently surfactants. Suitable air-entrainment additives with instructions for their use are commercially available.

· Accelerators speed the setting of the mortar. They may be especially useful in cold-weather application. Examples of common accelerants include calcium nitrate, calcium nitrite, calcium formate and certain aluminum compounds. Accelerator formulations with instructions for their use are commercially available.

· Retarders slow the setting time of the mortar. Examples of common retarders include calcium, sodium and ammonium salts of lignosulfonic acid, hydroxycarboxylic acids such as hydroxylic acid, carbohydrates, lead oxides, zinc oxides, phosphates, borates and fluorates. Retarder formulations with instructions for their use are commercially available.

· Superplasticizers allow the production and use of mortar with lower water content. Examples of superplasticizers include sulfonated melamine-formaldehyde condensates, sulfonated naphthalene-formaldehyde condensates, modified lignosulfonates and polycarboxylates. Superplasticizer formulations with instructions for their use are commercially available.

· Defoamers can reduce air-entrainment and voids in the mortar. Examples of defoamers include mineral oils, polyglycols and polyethersiloxanes. Defoamers with instructions for their use are commercially available.

In some embodiments, the dry mix/mortar contains at most 20 weight percent of the other additives or at most 10 weight percent or at most 5 weight percent or at most 2 weight percent, based on the dry components and excluding water. In some embodiments, the dry mix/mortar contains no measurable content of the other additives (essentially 0 weight percent) or at least 1 weight percent or at least 2 weight percent, based on the weight of dry components and excluding water.

To make the dry mix, the dry components are blended together. Suitable dry blending techniques are known, and suitable equipment to practice the techniques is commercially available.

To make the mortar, the dry components are thoroughly mixed with water, either separately or together as a dry mix, as previously described. The best quantity of water varies depending on the dry components and their intended use, and can be readily determined by experimentation. In some embodiments, the amount of water is at least 20 weight percent of the weight of the dry components, or at least 22 weight percent or at least 24 weight percent or at least 26 weight percent. In some embodiments, the amount of water is at most 60 weight percent of the weight of the dry components, or at most 50 weight percent or at most 40 weight percent or at most 30 weight percent.

In some embodiments, the quantity of water is selected to provide a mortar that, when wet, is on the one-hand fluid enough that it can be applied smoothly to a substrate and is on the other hand viscous enough that it will hold tiles to the substrate without excessive slippage or falling of tiles before the mortar sets. In some embodiments, the mortar has a viscosity of at least 300 Pa·s or at least 350 Pa·sor at least 400 Pa·sor at least 450 Pa·s or at least 500 Pa·sor at least 525 Pa·s or at least 550 Pa·s. In some embodiments, the mortar has a viscosity of at most 800 Pa·s or at most 700 Pa·s or at most 650 Pa·s or at most 600 Pa·s.

In one embodiment, the mortar contains:

a) From 20 to 50 weight percent cement;

b) From 25 to 65 weight percent inorganic filler;

c) From 1 to 10 weight percent organic binder suitable for use in tiling mortar;

d) from 3 to 15 weight percent of recycled composite fibers that have an average diameter of no more than 50 micron and an average length of no more than 800 micron,

e) water,

wherein all weight percentages are based on the weight of the dry components (a) - (d) , excluding the water. It may optionally further contain from 0 to 20 weight percent other additives as previously discussed. The selection and quantity of each component may optionally reflect the embodiments and examples previously discussed.

Among other uses, the mortar can be used for ordinary tiling. First, the mortar is applied to a substrate. Second, tiles are pressed onto the applied mortar. Third, the mortar is allowed to set. Each of these steps is well-known.

Examples of appropriate substrates include any known rigid building material, such as drywall, wood, plaster or concrete. Examples of suitable tiles include any known tiles such as ceramic, glass, porcelain, stone or marble, terra cotta or concrete.

Average thickness of the mortar varies depending on a number of factors such as the smoothness of the substrate and the tiles and the intended use. In some embodiments, the mortar is applied with a thickness (when wet) of at least 2 mm or at least 3 mm or at least 4 mm. In some embodiments, the mortar is applied with a thickness (when wet) of at most 10 mm or at most 9 mm or at most 8 mm or at most 6 mm or at most 5 mm. Setting causes the mortar to shrink. In some embodiments, the set mortar is at least 1 mm thick or at least 1.25 mm or at least 1.5 mm. In some embodiments, the set mortar is at most 6 mm thick or at most 5 mm or at most 4 mm or at most 3 mm.

Setting time for the mortar depends on many factors such as temperature, water content and components of the mortar. In some embodiments, setting time is between 300 and 700 minutes. In some embodiments, it may be longer or shorter.

In some embodiments, when tested according to the Test Methods the mortar provides a tensile adhesion after curing at room temperature of at least 0.5 N/mm ² or at least 0.75 N/mm ² or at least 1 N/mm ² or at least 1.1 N/mm ² or at least 1.2 N/mm ² or at least 1.3 N/mm ². There is no maximum desired tensile adhesion, but in many embodiments, adhesion above 3 N/mm ² or 2 N/mm ² provides little added value.

In some embodiments, when tested according to the Test Methods the mortar has a transverse deformation of at least 2.5 mm or at least 2.6 mm or at least 2.8 mm or at least 3 mm. In some embodiments, when tested according to the Test Methods the mortar has a transverse deformation of at most 8 mm or at most 6 mm or at most 5 mm or at most 4.5 mm or at most 4 mm or at most 3.75 mm.

The process produces a tiled surface comprising:

1. a substrate;

2. a plurality of tiles; and

3. a set mortar adhering the tiles to the substrate, wherein the mortar contains: (a) cement, (b) an inorganic filler, (c) an organic binder suitable for use in tiling mortar; and (d) from 3 to 15 weight percent of recycled composite fibers that have an average diameter of no more than 50 micron and an average length of no more than 800 micron, wherein all weight percentages are based on the weight of the dry components (a) - (d) .

Options and specific embodiments for the substrate, tiles and mortar are previously described, except the mortar has been allowed to set, so that it no longer contains the high level of water in the wet mortar. Ratios of dry components are as previously described.

EXAMPLES

Test Methods

Parameters described in this application can be measured using the following measurements:

Molecular Weight

Molecular weight/molecular weight distribution and a Mark-Houwink plot for branching structure analysis are measured using Triple Detector Gel Permeation Chromatography. The processes and equations utilized are described in US Patent No. 8,871,887. US Patent No. 8,871,887 is incorporated by reference. For the Gel Permeation Chromatography (GPC) processes (Conventional GPC, Light Scattering (LS) GPC, Viscometry GPC and gpcBR) , a Triple Detector Gel Permeation Chromatography (3D-GPC or TDGPC) system is utilized. This system includes a Robotic Assistant Delivery (RAD) high temperature GPC system [other suitable high temperature GPC instruments include Waters (Milford, Mass. ) model 150C High Temperature Chromatograph; Polymer Laboratories (Shropshire, UK) Model 210 and Model 220; and Polymer Char GPC-IR (Valencia, Spain) ] , equipped with a Precision Detectors (Amherst, Mass. ) 2-angle laser light scattering (LS) detector Model 2040, an IR4 infra-red detector from Polymer ChAR (Valencia, Spain) , and a 4-capillary solution viscometer (DP) (other suitable viscometers include Viscotek (Houston, Tex. ) 150R 4-capillary solution viscometer (DP) ) . A GPC with these latter two independent detectors and at least one of the former detectors can be referred to as “3D-GPC” or “TDGPC, ” while the term “GPC” alone generally refers to conventional GPC. Data collection is performed using software, e.g., Polymer Char GPC-IR. The system is also equipped with an on-line solvent degassing device, e.g., from Polymer Laboratories.

Eluent from the GPC column set flows through each detector arranged in series, in the following order: LS detector, IR4 detector, then DP detector. The systematic approach for the determination of multi-detector offsets is performed in a manner consistent with that published by Balke, Mourey, et al. (Mourey and Balke, Chromatography Polym., Chapter 12, (1992) ) (Balke, Thitiratsakul, Lew, Cheung, Mourey, Chromatography Polym., Chapter 13, (1992) ) . Olexis LS columns is used. The sample carousel compartment is operated at 140 ℃ and the column compartment is operated at 150 ℃. The samples are prepared at a concentration of 0.1 grams of polymer in 50 milliliters of solvent. The chromatographic solvent and the sample preparation solvent is 1, 2, 4-trichlorobenzene (TCB) containing 200 ppmw of 2, 6-di-tert-butyl-4methylphenol (BHT) . The solvent is sparged with nitrogen. The polymer samples are gently stirred at 160 ℃ for four hours. The injection volume is 200 microliters. The flow rate through the GPC is set at 1 ml/minute.

For Conventional GPC, the IR4 detector is used, and the GPC column set is calibrated by running 21 narrow molecular weight distribution polystyrene standards. The molecular weight of the standards ranged from 580 g/mol to 8, 400,000 g/mol, and the standards are contained in six “cocktail” mixtures. Each standard mixture had at least a decade of separation between individual molecular weights. The polystyrene standards are prepared at 0.025 g in 50 mL of solvent for molecular weights equal to, or greater than, 1,000,000 g/mol, and at 0.05 g in 50 mL of solvent for molecular weights less than 1,000,000 g/mol. The polystyrene standards are dissolved at 80 ℃., with gentle agitation, for 30 minutes. The number average molecular weight, the weight average molecular weight, and the z-average molecular weight are calculated from equations, e.g., as described in US Patent No. 8,871,887.

For the LS GPC, the Precision Detector PDI2040 detector Model 2040 is used. For 3D-GPC, absolute weight average molecular weight is calculated from equations, e.g., as described in US Patent No. 8,871,887. The gpcBR branching index is determined by calibrating the light scattering, viscosity, and concentration detector and subtracting the baselines. Integration windows are set for integration of the low molecular weight retention volume range in the light scattering and viscometer chromatograms that indicated the presence of detectable polymer from the refractive index chromatogram. Linear polyethylene standards are used to establish polyethylene and polystyrene Mark-Houwink constants. The constants are used to construct two linear references, conventional calibrations for polyethylene molecular weight and polyethylene intrinsic viscosity as a function of elution volume, e.g., as described in US Patent No. 8,871,887. To determine the gpcBR branching index, the light scattering elution area for the sample polymer is used to determine the molecular weight of the sample. Analysis is performed using the final Mark-Houwink constants, e.g., as described in US Patent No. 8,871,887.

Examples

A series of dry mixes are made by blending the dry ingredients listed in Table 1. The examples labeled IE are inventive examples that contain recycled composite fibers. The examples labeled CE are comparative examples that do not contain recycled composite fibers. Each dry mix is blended with water to make a mortar.

Each mortar is used to prepare specimens according to ISO 130007-2, using a rectangular frame (Template A) with internal dimensions being (280 ± 1) mm × (45 ± 1) mm × (5 ± 0.1) mm and a non-absorbent mold (Template B) of dimensions being (300 ± 1) mm × (45 ± 1) mm × (3 ±0.1) mm for transverse deformation test. Hold the template A firmly onto the polyethylene film. Trowel sufficient adhesive across the template and then screed clean such as to fill the hole in the template neatly and completely. Clamp the mold firmly to the flow table and compact the sample using 70 jolts. Lift the mound gently from the flow table and carefully remove the template vertically. Apply a layer of release agent to the template B and position it centrally over the specimen. Load the template with a mass capable of exerting a force of (100 ± 0.1) N and an approximate cross-sectional area of (290 × 45) mm. The applied pressure ensures that the material fully fills the recess of the template to the required thickness. Remove any excess material from the sides of the template and 1 h later, remove the mass. The specimens are demolded 48 hrs. after preparation. They are cured in air-tight plastic containers for 12 days under (23 ± 2) ℃, and then another 14 days cure under (23 ± 2) ℃ and (50 ± 5) %RH. The thickness of specimens needs to be (3.0 ± 0.1) mm. Any specimen that falls outside the required thickness for the transverse deformation test is discarded.

For tensile adhesion strength test, the fresh mortar paste is applied as a thin layer on a concrete slab with a straight edge trowel. Then a thicker layer is applied and combed with a notched trowel 6*6 mm. The trowel is held at an angel of approximately 60° to the substrate at a right angle to one edge of the slab and drawn across the slab parallel to the edge (in a straight line) . Tiles are then placed 5 min after the mortar is applied, and a load of (20 ± 0.05) N is placed on tiles for 30 s to ensure the tiles are set in the wet mortar. They are cured under (23 ± 2) ℃ and (50 ± 5) %R for 28 days.

Transverse deformation and tensile adhesion are tested using the Test Methods listed above. Results are listed in Table 1.

All proportions listed in the table are in weight percent of total weight of dry mix components, excluding water.

1 –Product of The Dow Chemical Company.

2 –Product of Longbing Lide Company, Ltd. The recycled composite fibers are recovered from end-of-life win contain glass fibers covered with a layer of thermo-set resin on surface. RCF-Acontains 66%glass fiber and 34 Particle size of RCF-Amainly falls in between 300-500 micron. RCF-B contains 73%glass fiber and 27%pol

Claims

A dry mix comprising:

(a) cement;

(b) an inorganic filler wherein 95 to 100 weight percent of filler particles will pass through a sieve of 2.36 mm;

(c) an organic binder suitable for use in tiling mortar;

(d) from 3 to 15 weight percent of recycled composite fibers that have an average diameter of no more than 50 micron and an average length of no more than 800 micron,

wherein all weight percentages are based on the weight of the dry components (a) - (d) .
The dry mix of Claim 1 wherein dry mix contains from 5 to 10 weight percent of recycled composite fibers.
The dry mix of any one of Claims 1 or 2 wherein the average diameter of the recycled composite fibers is from 10 to 40 microns.
The dry mix of any one of Claims 1 to 3 wherein the average length of the recycled composite fibers is from 200 to 500 microns.
The dry mix of any one of Claims 1 to 4 wherein the recycled composite fibers comprise glass fibers.
The dry mix of any one of Claims 1 to 5 wherein the recycled composite fibers comprise cured thermoset resin adhered to the fibers.
The dry mix of any one of Claims 1 to 6 wherein the recycled composite fibers comprise from 20 to 40 weight percent cured epoxy resin and from 60 to 80 weight percent fibers, wherein the weight percentages are based on the total weight of the recycled composite fibers.
The dry mix of any one of Claims 1 to 7 wherein 95 percent to 100 percent of the filler particles have a diameter of no more than 1 mm.
A mortar comprising the dry mix components listed in any one of Claims 1 to 8 and further comprising (e) water.
A process to use the mortar in the mortar in Claim 9 to affix tiles to a substrate, comprising the steps of:

(a) applying the mortar to a substrate;

(b) applying a plurality of tiles to the mortar on the substrate; and

(c) permitting the mortar to set.