The properties of many commercial stain blockers are frequently not retained during washing of the substrate treated with said stain blocker, suffer from light fastness limitations, and have marginal resistance to coffee and mustard stains. Many commercial products when blended with phenol-formaldehyde resins provide better stain blocking and durability, but still provide only limited UV stability (light fastness) and have limited coffee and mustard stain resistance.
Allen, in U.S. Pat. No. 5,574,106, discloses polymers wherein a strong acid-containing monomer, a weak acid-containing monomer, and a neutral aromatic-containing monomer are polymerized. More specifically, Allen describes stain resist compositions formed from (a) from about 8% to about 40% of a styrene, substituted styrene or phenolic monomer free of carboxylic acid groups and strong acid groups, (b) from about 9% to about 20% of an ethylenically unsaturated strong acid monomer having a pKa below 2, and (c) from about 10% to about 62% of an ethylenically unsaturated weak acid monomer having a pKa of 3-11, with the weight percentages described in a ternary diagram. In addition, Allen discloses (a) a preferred system in which the polymers are mixed with sulfonated phenolic condensates, and (b) that the aromatic neutral monomer must be free of acidic groups. Allen does not describe the use of phenols that have weakly acidic groups, nor the use of a preformed co-polymer that is sulfonated.
It is desirable to have stain blockers having improved performance. In particular, improved stain resistance to coffee and mustard stains is desirable while maintaining UV fastness and durability of the properties. The present invention provides such a stain blocker composition, method for its use, and substrates treated therewith.
The present invention comprises a composition comprising a polymer having the following repeating units, said units occurring in any sequence
wherein
R1 is H, methyl or ethyl;
R2 and R3 are each independently H, C1 to about C10 alkyl, —COOR4, CONR5R6, or —CN;
R4 is M, C1 to about C20 alkyl, or C6 to C10 aryl;
R5 and R6 are each independently H, C1 to C10 alkyl, C6 to C10 aryl, or R5 and R6 together with the nitrogen atom form a morpholine, pyrrolidine, or piperidine ring;
R7 is a C4 to C8 alkyl group;
M is H, an alkali metal or alkali earth metal;
h is about 10 to 100 mole %;
i is 0 to about 80 mole %;
j is 0 to about 60 mole %;
k and n are each independently 0 to about 40 mole %; and
m is 0.01 to about 0.5;
provided that h+i+j+k+n equals 100, and
provided that i+j+k+n is greater than zero, except when h is 100%.
The present invention further comprises a method of providing resistance to stains in substrates comprising contacting the substrate with a polymer of Formula 1A having the following repeating units, said units in any sequence
wherein
R1 is H, methyl or ethyl;
R2 and R3 are each independently H, C1 to about C10 alkyl, —COOR4, CONR5R6, or —CN;
R4 is M, C1 to about C20 alkyl, or C6 to C10 aryl;
R5 and R6 are each independently H, C1 to C10 alkyl, C6 to C10 aryl, or R5 and R6 together with the nitrogen atom form a morpholine, pyrrolidine, or piperidine ring;
R7 is a C4 to C8 alkyl group;
M is H, an alkali metal or alkaline earth metal;
h is about 10 to 100 mole %;
i is 0 to about 80 mole %;
j is 0 to about 60 mole %;
k and n are each independently 0 to about 40 mole %; and
p is 0 to about 0.5;
provided that h+i+j+k+n equals 100, and
provided that i+j+k+n is greater than zero, except when h is 100%.
The present invention further comprises a substrate treated with a polymer of Formula 1A as described above.
The present invention further comprises a composition comprising a polymer of Formula 2 having the following repeating units, said units occurring in any sequence
wherein
R1 is H, methyl or ethyl;
R2 and R3 are each independently H, C1 to about C10 alkyl, —COOR4, CONR5R6, or—CN;
R4 is H, C1 to about C20 alkyl, or C6 to C10 aryl;
R5 and R6 are each independently H, C1 to C10 alkyl, C6 to C10 aryl, or R5 and R6 together with the nitrogen atom form a morpholine, pyrrolidine, or piperidine ring;
R7 is a C4 to C8 alkyl group;
R8 is H, C1 to about C20 alkyl, or C6 to C10 aryl;
R9 is H, R10, or C(O)R11;
R10 is C1 to about C4 alkyl;
R11 is C1 to about C4 alkyl, or C6 to C10 aryl;
h is about 10 to 100 mole %;
i is 0 to about 80 mole %;
j is 0 to about 60 mole %;
k and n are each independently 0 to about 40 mole %; and
m is 0.01 to about 0.5;
provided that h+i+j+k+n equals 100, and
provided that i+j+k+n is greater than zero, except when h is 100%.
Herein trademarks are shown in upper case. As used herein, the term “(alkyl)acrylic” indicates acrylic or alkylacrylic, and the term “(alkyl)acrylate” indicates acrylate or alkylacrylate.
The first embodiment of the present invention comprises polymers of Formula 1 having the following repeating units occurring in any sequence.
wherein
R1 is H, methyl or ethyl and preferably H or methyl;
R2 and R3 are each independently H, C1 to about C10 alkyl, —COOR4, CONR5R6, or —CN;
R4 is M, C1 to about C20 alkyl, or C6 to C10 aryl;
R5 and R6 are each independently H, C1 to C10 alkyl, C6 to C10 aryl, or
R5 and R6 together with the nitrogen atom form a morpholine, pyrrolidine, or piperidine ring;
R7 is a C4 to C8 alkyl group;
M is H, an alkali metal or an alkaline earth metal, and preferably Na or K;
h is about 10 to 100 mole % and preferably about 40 to about 70 mole %;
i is 0 to about 80 mole % and preferably about 30 to about 60 mole %;
j is 0 to about 60 mole % and preferably about 30 to about 60 mole %;
k and n are each independently 0 to about 40 mole % and preferably about 0 to about 10 mole %;
m, also denoted herein as the degree of sulfonation, is from about 0.01 to about 0.5, and preferably from about 0.01 to about 0.4 sulfonic acid groups per hydroxystyrene monomer residue; and
h+i+j+k+n equals 100, and
i+j+k+n is greater than zero, except when h is 100%.
The sulfonated homopolymer of hydroxystyrene is represented by Formula 1 in which i, j, k, and n are zero. The sulfonation of the hydroxystyrene is random throughout the polymer.
Preferred polymers of the structure of Formula 1 are a) polymers having j =k=n=0 and the ratio of h:i from about 50:50 to about 70:30, and preferably about 60:40, or b) polymers having i=k=n=0 and the ratio of h:j from about 50:50 to about 70:30, and preferably about 60:40.
The polymers of the present invention are useful to provide stain resistance to substrates. In particular, improved resistance to staining by coffee and mustard is provided to substrates treated with the polymers of the present invention.
Polymers of the structure of Formula 1 are formed by polymerization of (a) hydroxystyrene, t-butoxystyrene, acetoxystyrene, alkoxystyrene, or other protected hydroxystyrenes, and (b) one or more monomers of i) monomers of the structure of Formula 3 (see below), ii) maleic anhydride, iii) styrene, and iv) a terminally unsaturated alkene.
The monomer of Formula 3 is an (alkyl)acrylic acid or an (alkyl)acrylate ester having the following formula:
R2R3C=C(R1)—COOR8 Formula 3
wherein
R1 is H, methyl or ethyl, and preferably H or methyl;
R2 and R3 are each independently H, C1 to about C10 alkyl, —COOR4, CONR5R6, or —CN, and preferably R2 is H and R3 is —COOR4;
R5 and R6 are each independently H, C1 to C10 alkyl, C6 to C10 aryl, or R5 and R6 together with the nitrogen atom form a morpholine, pyrrolidine, or piperidine ring, and preferably R5 and R6 are independently H or methyl, and
R8 is H, C1 to about C20 alkyl, or C6 to C10 aryl, and preferably H or methyl.
Examples of Formula 3 are (alkyl)acrylic acids, such as (meth)acrylic acids, and their esters, such as methyl and t-butyl (meth)acrylates. The free acids are preferred for emulsion polymerization, and the esters for solution polymerization. When the esters are used, the alkyl group R8 is removed during subsequent hydrolysis steps.
The preparation of the polymers of Formula 1 is by use of polymerization procedures known to those skilled in the art. Polymerizations and the removal of protective groups are discussed in Sheehan et al. in US Patent 2002156199, Watanabe et al. in U.S. Pat. No. 5,412,050, and Lin et al., in “Sequence Distribution and Polydispersity Index affect the Hydrogen-Bonding Strength of Poly(vinylphenol-co-methyl methacrylate) Copolymers”, Macromolecules, 2005, 38, 6435-6444, each herein incorporated by reference. Emulsion and solution polymerization procedures are well know to those skilled in the art, for instance Rupp et al. discuss suitable emulsion polymerization procedures in U.S. Pat. No. 4,822,862, and Gupta discusses suitable solution polymerization procedures in U.S. Pat. No. 4,775,730, each herein incorporated by reference.
The procedures for making polymers of the structure of Formula 1 wherein i, k, and n, are zero are know to those skilled in the art, for instance see “Preparation and Structural Characterization of Poly(4-vinylphenylacetate-co-maleic anhydride”, J. A. Jones and R. M. Ottenbrite, J. Polym. Chem, Part A: Polymer Chemistry, Vol. 24, 1487-95(1986), herein incorporated by reference. In the practice of the present invention, any hydroxystyrene, t-butoxystyrene, acetoxystyrene, alkoxystyrene, or other protected hydroxystyrene isomer or mixture thereof may be used, the para isomers are preferred. Several factors are involved with the choice of t-butoxystyrene, acetoxystyrene, or hydroxystyrene as the monomer introducing the hydroxystyrene moiety into the polymer. Hydroxystyrene is relatively unstable and can be the source of undesirable impurities. Polymers made with hydroxystyrene may be discolored or require the use of special solvents.
The polymerization yields an intermediate polymer having the structure of Formula 2 below.
wherein
R1 is H, methyl or ethyl;
R2 and R3 are each independently H, C1 to about C10 alkyl, —COOR4, CONR5R6, or —CN;
R4 is H, C1 to about C20 alkyl, or C6 to C10 aryl;
R5 and R6 are each independently H, C1 to C10 alkyl, C6 to C10 aryl, or R5 and R6 together with the nitrogen atom form a morpholine, pyrrolidine, or piperidine ring;
R7 is a C4 to C8 alkyl group;
R8 is H, C1 to about C20 alkyl, or C6 to C10 aryl;
R9 is H, R10, or C(O)R11;
R10 is C1 to about C4 alkyl;
R11 is C1 to about C4 alkyl, or C6 to C10 aryl;
h is about 10 to 100 mole %;
i is 0 to about 80 mole %;
j is 0 to about 60 mole %;
k and n are each independently 0 to about 40 mole %; and
m is 0.01 to about 0.5;
provided that h+i+j+k+n equals 100, and
provided that i+j+k+n is greater than zero, except when h is 100%.
These intermediate polymers of Formula 2 comprise a further embodiment of the present invention, and are useful in making the polymers of Formula 1. Hydrolysis of the polymer of Formula 2 yields the polymer of Formula 1.
Any alkoxy groups, for instance acetoxy groups, if present, are removed by hydrolysis or preferably by base-mediated transesterification as described by Sheehan et al, in U.S. Pat. No. 6,759,483. If present, the ester group C(O)OR4 is removed by suitable hydrolysis based on the type of ester group, for example the t-butyl group is removed by acid hydrolysis effected by well known reagents such as HCl or trifluoroacetic acid. If present, the cyclic anhydride ring is opened by base hydrolysis. The hydroxystyrene monomer residues are optionally sulfonated.
The alkoxy groups are to be removed after polymerization whether or not the polymer is subsequently sulfonated. All protecting groups impede sulfonation. Examples of alkoxy groups include, but are not limited to, t-butoxy, acetoxy, and methoxymethyl (—CH2OCH3). The t-butoxy and methoxymethyl groups are easily removed by acid hydrolysis, while the acetoxy group is readily removed by base hydrolysis or transesterification. Although the acetoxy group is less easy to remove, requiring base hydrolysis, the monomer is less expensive and more readily available. When present, the maleic anhydride ring (Formula 1 wherein j is greater than zero) is opened by a base hydrolysis before use as the stain resist. Preferably, the anhydride ring is opened after the alkoxy (for instance acetoxy) group has been removed. Hydrolysis of the polymer of Formula 2 yields the polymer of Formula 1.
The sulfonation of the hydoxystyrene moieties in the polymers of Formula 1 is also accomplished by means known to those skilled in the art. For instance, sulfonation can be achieved by treatment of the polymer with sulfuric acid of various concentrations, by the use of fuming sulfuric acid, and most readily by the use of sulfur trioxide or its complexes, including the dimethylformamide complex or the dioxane complex. Sulfonation occurs on the hydroxystyrene residue, predominantly ortho to the hydroxy group for p-hydroxystyrene or ortho or para to the hydroxy group for other hydroxystyrene isomers. When styrene monomer is present in the polymer, sulfonation occurs preferentially on the hydroxystyrene monomer moiety.
The term “degree of sulfonation”, represented by m in Formula 1, is used to describe the average number of sulfonic acid groups per hydroxystyrene residue. A degree of sulfonation of zero is the unsulfonated polymer, a degree of sulfonation greater than zero to less than 1.0 denotes an average of less than one sulfonic acid group per hydroxystyrene residue. For steric reasons there will be a degree of randomness in the sulfonation along the polymer chain. The degree of sulfonation for Formula 1 is from about 0.01 to about 0.5 and preferably about 0.01 to about 0.4.
Sulfonation adds a strongly acidic group to the polymer which is expected to exist in an anionic state under conditions relevant to application of stain blockers to substrates. This renders unoccupied dye sites in the treated substrate less available to potential staining. Sulfonation also increases the water solubility of the polymers and hydrolyzed polymers, an important factor in their application as stainblockers.
The sulfonated polymer of Formula 1 is isolated. For example, by removing the dimethylformamide solvent and then precipitating in a non-solvent such as diethyl ether or hexane. The solid polymer thus obtained can be re-dissolved in a solvent such as methanol and optionally reprecipitated to remove impurities. The polymer is then redissolved or dispersed in water at a concentration of from about 15% to about 30% by weight solids to provide a formulation for treatment of substrates. The aqueous solutions are adjusted to a neutral pH range of about 6 to about 7.
Unsulfonated polymers are also useful in the present invention to provide stain resistance to substrates. These are included in Formula 1A below.
wherein
R1, R2, R3, R4, R7, M, h, i, j, k, and n are defined as in Formula 1 and p is 0 to about 0.5. Formula 1A is the same structure as Formula 1 except that p is 0 to about 0.5, and preferably 0 to about 0.4. Unsulfonated polymers of Formula 1A are prepared and isolated as described above for the sulfonated polymers except that the sulfonation step is omitted when p is zero. For polymers of Formula 1A, p represents the degree of sulfonation as described above for m of Formula 1.
In a further embodiment, the present invention comprises the use of aqueous solutions or dispersions of (a) polymers of Formula 1, (b) polymers of Formula 1A, or (c) mixtures thereof as stain resist agents for substrates. The invention comprises a method of treating substrates to provide stain resistance comprising contacting the substrate with at least one polymer of the structure of Formula 1 or Formula 1 A as described above, or mixtures thereof.
The dispersions or solutions of the polymers of Formula 1, Formula 1A, or mixtures thereof, are applied conventionally to the substrate, dried, and cured. Application methods include spray, foam flex-nip, pad, kiss-roll, beck, skein, and winch, brush, roll, spray, and immersion, each method optionally with heat and with humidity in the range of dry to saturated steam (100% relative humidity). In alternative embodiments of the present invention, spray, foam, flex-nip, nip (dip and squeeze), liquid injection, overflow flood, and other application methods well known to those skilled in the art, are suitable for use for simultaneous, tandem or sequential application of the stain resist polymers of the present invention and other surface effect agents. For instance, a low wet pickup bath system can be interchanged with a low wet pickup spray or foam system, and a high wet pickup bath system can be interchanged with other high wet pickup systems, e.g., flex-nip system, foam, pad, or flood. The method employed determines the appropriate wet pickup and whether the application is made from one side of the substrate (spray and foam applications) or both sides (flex-nip and pad).
The following Table provides typical parameters for some application methods for the compositions of the present invention.
Many variations of the conditions for spray, foam, flex-nip, flood, and pad applications are known to those skilled in the art and such variations are suitable for use herein. In one preferred method for carpet substrates the application is by exhaution at a wet pickup of 500% at a concentration of polymer of from about 0.5% to about 3% active ingredient on weight of fiber (owf), preferably from about 1 to about 2% active ingredient owf. The percent active ingredient owf is equal to the wet pickup multiplied by (percent solids of polymer times amount of polymer in g divided by weight of application bath).
Other treatment aids that are known to those skilled in the art may be added to the solutions or dispersions of polymers of the structure of Formula 1, Formula 1A, or mixtures thereof, including additional components such as treating agents or finishes to achieve additional surface effects, or additives commonly used with such agents or finishes. Such additional components comprise compounds or compositions that provide surface effects such as no iron, easy to iron, shrinkage control, wrinkle free, permanent press, moisture control, softness, strength, anti-slip, anti-static, anti-snag, anti-pill, stain repellency, stain release, soil repellency, soil release, water repellency, oil repellency, odor control, antimicrobial, sun protection, and similar effects. One or more such treating agents or finishes can be combined with the aqueous solution or dispersion of Formula 1 or 1A and applied to the fibrous substrate. Other additives commonly used with such treating agents or finishes may also be present such as surfactants, blocked isocyanates, pH adjusters, cross linkers, wetting agents, hydrocarbon extenders, wax extenders, and other additives known by those skilled in the art. Suitable surfactants include anionic, cationic, and nonionic. Preferred is an anionic surfactant such as sodium lauryl sulfonate, available as DUPONOL WAQE from Witco Corporation, Greenwich, Conn.
In a further embodiment, the present invention comprises substrates treated with at least one composition of Formula 1, or at least one composition of Formula 1 A, or mixtures thereof. Substrates suitable for use in the present invention comprise fibrous substrates and include fibers, yarns, fabrics, textiles, nonwovens, carpets, leather, or paper. The fibrous substrates are made with natural fibers such as wool, cotton, jute, sisal, sea grass, paper, coir and cellulose, or mixtures thereof; or are made with synthetic fibers such as polyamides, polyesters, polyolefins, polyaramids, acrylics and blends thereof; or blends of at least one natural fiber and at least one synthetic fiber. By “fabrics” is meant natural or synthetic fabrics, or blends thereof, composed of fibers such as cotton, rayon, silk, wool, polyester, polypropylene, polyolefins, nylon, and aramids such as “NOMEX” and “KEVLAR.” By “fabric blends” is meant fabric made of two or more types of fibers. Typically these blends are a combination of at least one natural fiber and at least one synthetic fiber, but also can be a blend of two or more natural fibers or of two or more synthetic fibers.
The substrates are treated with the polymer of Formula 1 or Formula 1A or mixtures thereof as described above. Preferably, the substrates are treated in accordance with the method of the present invention described above.
Substrates so treated were superior to current commercial products in blocking coffee and mustard stains, while many retained stain resistance to red dyes such as KOOL-AID, wash fastness and lightfastness. The superior stain resistance of the polymers and treated substrates of the present invention provide several advantages. For example, the superior resistance to coffee and mustard stains is advantageous in use of the treated substrates in fabrics and textiles used in garments, home furnishings, carpets, and other consumer products. The durability of the stain resistance when subjected to washing or UV light results in superior performance over time.
The following materials and test methods were employed in the Examples herein.
Sulfur trioxide N,N-dimethylformamide complex (SO3.DMF), is available from Aldrich Chemical, Milwaukee Wis.
Poly(p-hydroxystyrene), poly(p-hydroxystyrene-co-t-butylacrylate) (61:39), poly(p-hydroxystyrene-co-t-butylacrylate) (61:39), and poly(p-hydroxystyrene) branched are all available from Du Pont Electronic Polymers, LLP, Corpus Christi Tex.
Comparative Example A is a commercially available stain blocker composition which is an aqueous dispersion of an olefin/maleic acid polymer with phenol-formaldehyde resin and surfactant, obtained from E. I. du Pont de Nemours and Company, Inc., Wilmington Del.
The carpet material is a residential cut pile two ply 1150, 3.5 turns per square inch (1.4 turns/cm), 5/32 gauge, pile height 0.5 inch (2.5 cm), 30 oz. per square yard (1.2 kg/m3), dyed light blue and available from Invista, Wilmington, Del.
Test Method 1—Application of Stain Resist onto Residential Carpet with Exhaust in a Microwave Oven
Dyed and unbacked residential carpet (with various colors, styles, and fiber types) were cut into approximately 4 inch×4 inch squares (approximately 10 cm×10 cm) and each square weighed as dry carpet samples. The weight was typically about 13 g. Each carpet sample was saturated with water and then most of the water in the carpet was removed by mechanical means (such as by spin-drying or vacuum extraction) until the weight of water remaining in the carpeting was about 40% of the dry carpet weight.
The stain blocker application solutions were diluted to 2% active ingredient on weight of fiber (owf) (2% of the total water bath by weight). Surfactant, DOWFAX 2A4 (1 to 2 g), was added to the solution, and the solution was adjusted to pH 2 with sodium bisulfate. The solution was applied to the carpet at 500% wet pick up. The weight of carpet sample (grams) ×500% =grams of stain blocker solution applied. The stain blocker application solution was applied evenly to the wetted carpet samples in an amount equal to 500% of the dry carpet sample (500% wet pickup), and manually worked into the substrate until the substrate was fully saturated.
A single layer of one or more of the treated carpet samples was placed on the bottom of a microwave-safe plastic tray (any microwaveable plastic tray of adequate size may be used) with the pile side up. A few holes were punctured in the lid to prevent steam buildup, and the lid was placed on the plastic tray.
Using a household microwave oven with a temperature probe (such as a General Electric model JVM1660, from General Electric, Schenectady N.Y.), the carpet was heated in the plastic tray at full power level until the temperature reached between 195+/−2° F. (91+/−1° C.) and the temperature held at that temperature for 2 minutes. The microwave oven temperature probe was used to control the temperature. The samples were then rinsed thoroughly with water.
Most of the water in the carpet sample was removed by spin-drying with an extractor until the weight of water remaining in the carpeting was about 20 to 40% of the dry carpet weight. The carpet sample was then completely dried in an oven at between 160° F. and 180° F. (70° C. and 80° C.); typically for about 25 to 35 minutes. The carpet samples were allowed to cool completely, for at least 10-15 minutes, and to reach equilibrium with the room environment before proceeding with stain testing.
Although 2% active ingrediant owf was used in the Examples, it is suitable in the present invention to use a broader range of values calculated as follows:
% active ingredient on weight of the fiber (% AI owf)=[(% Solids in Stain Blocker×amount (g))/water bath total (g)]×wet pick up
The quantities of the stainblocker suitable for application to the carpet substrate are the amounts as calculated to achieve the 500% wet pick up. In the present invention, these amounts can range from about 0.5% to about 3% AI owf based on the weight of the substrate carpet sample, preferably from about 1 to about 2% AI owf.
Test Method 2—Coffee Stain Test
Carpet samples, 6.76×6.76-inch (17.2×17.2 cm) squares of dyed carpet, were cut and placed pile side up on a non-absorbent surface. The pile was cleaned of any unattached materials by vacuuming. ORIGINAL MAXWELL HOUSE ground coffee (33.8 g), available from Maxwell House Coffee Co., Tarrytown N.Y. was placed into a standard 10-cup coffee filter. Deionized water (1266.2 g) was added and the coffee brewed according to the manufacturers' directions. The pH of the coffee was adjusted to 5.0 using aqueous solutions containing either 30% aqueous sodium hydrogen sulfate or 10% sodium hydroxide as needed. The coffee was poured into a suitable volumetric dispenser, capable of dispensing 50 mL portions and the dispenser placed in the hot water bath at 62° C. The coffee was allowed to come to a temperature 140° F. +/−5° F. (60° +/−2.8° C.) and remain at that temperature for 30+/−5 minutes prior to staining. A ring, in the shape of an open-ended cylinder was used, having a diameter of the smaller opening of 2.75 inch (7 cm). Such a ring is described for a different purpose in AATCC Test Method 175. The ring was placed at the center of the carpet sample, with the smaller diameter opening against the pile. The coffee dispenser was set to measure 50 mL, and purged once prior to staining. With the ring pressed down into the pile, 50 mL of coffee was transferred into a container and immediately poured into the ring and onto the carpet. The coffee was worked into the carpet evenly and thoroughly with the base of the cup. The coffee was allowed to stain the carpet for 4 hours +/−20 minutes. Then the carpet samples were thoroughly rinsed in cold water for at least 10 minutes until the rinse water was clear. The carpet samples were extracted using vacuum and air-dried for 24 hours on a non-absorbent surface. The coffee stains obtained by this procedure were rated using a delta E color difference measurement.
For color measurement with delta E color difference, the color of each control and test carpet was measured both before and after the coffee stain test.
The initial color of the carpet (L*, a*, b*) was measured on an unstained piece of carpet. The delta E is the difference between the color of the unstained and stained samples, expressed as a positive number. The color difference was measured using a Minolta Chroma Meter CR-410. Color readings were taken on several areas on the carpet sample, and the average delta E was reported. Control carpets were of the same color and construction as the carpets for test items. A delta E reading of zero represents no color difference between two samples. A larger delta E value indicates a color difference between two samples. Color measurement with delta E is discussed in AATCC Evaluation Procedure 7 “Instrumental Assessment of the Change in Color of a Test Specimen”.
The calorimetric delta E values from the coffee stain resist test on a sample and control was used to calculate the “Percent Coffee Blocked”. The percent blocking of the stain is calculated as:
100(Delta Euntreated−Delta Etreated)/Delta Euntreated. Higher values denote better stain blocking.
Test Method 3—Mustard Stain Test
A 2 inch (5.1 cm) brass ring is placed in the center of a 4 to 6 inch (10.2 to 15.2 cm) square sample of carpet placed on a non-absorbent surface. For the mustard stain test, fifteen grams of French's yellow mustard available from Reckitt Benckiser, Inc., Wayne, N.J., were used to create a stain by placing the mustard in the middle of the brass ring on the carpet, and then spreading and pressing the stain into the carpet surface. After setting for 24 h, the excess mustard was (a) scraped off, (b) thoroughly rinsed with water, (c) extracted using vacuum, and (d) air-dried for 24 hours on a non-absorbent surface. The mustard stains obtained by this procedure were rated using a visual stain rating scale (AATCC Red 40 Stain Scale) from AATCC Test Method 175. A visual rating of 10 (complete stain removal) to 1 (maximum or unchanged stain) was used that approximated the AATCC Red 40 Stain Scale (Test Method #175) with the mustard stains having the same discoloration as the numbered colored film. The mustard stain was yellow while the discoloration of the AATCC Red 40 Stain Scale was red. Higher values indicate greater mustard stain resistance.
Test Method 4—Stain Test with Cherry Flavored KOOL-AID (24 h KA)
Cherry KOOL-AID stain testing was conducted on carpet samples 15 cm by 15 cm. Acid dye stain resistance was evaluated using a procedure based on the American Association of Textile Chemists and Colorists (AATCC) Method 175, “Stain Resistance: Pile Floor Coverings.” A staining solution was prepared by mixing 36.5 grams of sugar sweetened cherry KOOL-AID and 500 mL water. KOOL-AID is a trademark of Kraft General Foods, Inc. The carpet sample to be tested was placed on a flat non-absorbent surface and a hollow plastic cylinder having a 2-inch (5-cm) diameter was placed tightly over the carpet sample. Twenty mls. of KOOL-AID staining solution was poured into the cylinder and the solution was allowed to absorb completely into the carpet sample. The stain was worked into the carpet. The cylinder was then removed and the stained carpet sample was allowed to sit undisturbed for 24 h. Then the carpets were rinsed thoroughly under cold tap water for at least 10 minutes until the rinse water was clear. The carpet samples were extracted using vacuum and air-dried for 24 hours on a non-absorbent surface. The KOOL-AID stains obtained by this procedure were rated using a visual stain rating scale (AATCC Red 40 Stain Scale) from AATCC Test Method 175. A visual rating of 10 (complete stain removal) to 1 (maximum or unchanged stain) was obtained by using the AATCC Red 40 Stain Scale (Test Method #175) with the KOOL-AID stains having the same discoloration as the numbered colored film. Higher values represent superior stain resistance.
Test Method 5—UV Light Stability.
UV fastness was conducted according to the American Association of Textile Chemists and Colorists (AATCC) Test Method 16. The Nylon carpet samples were rated in accordance with the Grey Scale for color change after exposure to 40 AATCC AFU (adjusted fade units). A visual rating ranged from 5 (complete color fastness compared to an unexposed sample) to 1 (complete loss of color). A higher rating indicated superior UV light stability.
Test Method 6—Shampoo Test or Wash Durability “WAQE KA”
The carpet sample was submerged for 5 minutes at room temperature in a detergent solution consisting of “DUPONOL WAQE”(300 g WAQE/18.92 L). “DUPONOL WAQE” is a 30-40% aqueous solution of sodium alkane sulfonates, available from Witco Corporation, Greenwich CT. The solution was adjusted with 10% sodium phosphate to a pH of 9.8 to 10.2. The carpet sample was then removed, rinsed thoroughly under tap water, de-watered by squeezing, extracted by spinning dry, and allowed to dry at ambient temperature. The dry carpet sample was then tested and rated on a scale of 1 to 10 according to Test Method 4. A higher value indicates superior wash durability of the stain resist.
Into a 500-mL round-bottom flask was added poly(p-hydroxystyrene) (20 g, M.W. 11,200, Triquest LP) and dimethyl formamide (DMF, 160 mL). To the resulting solution was added sulfur trioxide N,N-dimethylformamide complex (SO3.DMF, 12.7 g g, 83.33 mmol). The reaction mixture was heated at 150° C. for 18 h in which time the solution went from yellow to amber. After cooling to room temperature the solvent was removed on a rotary evaporator. The resulting oil was re-evaporated several times from 50 mL methanol. The resulting oil was triturated with diethyl ether until a solid formed. The solid was collected by filtration and dried under vacuum to yield solid 50% sulfonated poly(p-hydroxystyrene), 32.6 g. Elemental analysis: C 54.78%, H 6.75%, N 5.71%, S 8.37%. A sample for testing was prepared by adding the above solid (15 g) to deionized water (75 mL) and of 1N NaOH (14 mL). This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2 and 4. Test results are shown in Table 2.
Into a 500-mL round-bottom flask was added poly(p-hydroxystyrene-t-butylacrylate) polymer (20 g, 61:39; Dupont Electronic Polymers LLP, Lot No# 10020-51-FDP, see Materials) and DMF (120 mL). To the resulting solution was added SO3.DMF (7.6 g) and the resulting solution heated at 150° C. with stirring for 18 h. The reaction mixture was cooled to room temperature and the solvent removed in vacuo to give a brown oil. The oil was added to diethyl ether (200 mL) and stirred for 30 min.; decanting the diethyl ether and repeating the procedure several times caused the polymer to solidify. The solid was dried under high vacuum to give the product, 50% sulfonated poly(p-hydroxystyrene-acrylic acid) (61:39), 28.17 g. 1H and 13C NMR showed that the t-butyl group had been removed in the course of the sulfonation. Elemental analysis: C 53.66%, H 7.08%, N 6.53%, S 5.62%. A sample for stain blocker testing was prepared by dissolving the above polymer (15 g) in deionized water (50 mL) and 1N NaOH (9.5 mL). This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2, 4, 5, and 6. Test results are shown in Tables 2 and 3.
Into a 500-mL round-bottom flask was added poly(p-hydroxystyrene-t-butylacrylate) polymer (20 g, 61:39; Dupont Electronic Polymers LLP, Lot No. 10020-51-FDP, see Materials) and DMF (120 mL). To the resulting solution was added SO3.DMF (3.8 g) and the resulting solution heated under nitrogen to 150° C. with stirring for 18 h. The reaction mixture was cooled to room temperature and the solvent removed in vacuo to give a brown oil. The oil was added to diethyl ether (150 mL) and stirred for 30 min. Decanting the diethyl ether and repeating the procedure several times caused the polymer to solidify. The solid was dried under high vacuum to give the product, 25% sulfonated poly(p-hydroxystyrene acrylic acid) (61:39), 26.48 g. 1H and 13C NMR showed that the t-butyl group had been removed in the course of the sulfonation. Elemental analysis: C 58.42%, H 7.47%, N 6.6%, S 3.09%. A sample for testing was prepared by dissolving the above polymer (15 g) in deionized water (60 mL) and adding 1 N NaOH (13 mL). This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Method 2. Test results are shown in Table 2.
Into a 500-mL round-bottom flask was added poly(-p-hydroxystyrene) (20.0 g, branched, Dupont Electronic Polymers LLP; Lot no: PB5-8007B; M.W. 4934, see Materials) and DMF (80 mL). To the resulting orange solution was added SO3.DMF (12.76 g). The reaction mixture was stirred and heated at 150° C. under nitrogen atmosphere for 18 h. After cooling to room temperature, the solvent was removed in vacuo and the resulting thick oil stirred under diethyl ether (200 mL) for 30 min. The diethyl ether was decanted off and the procedure repeated thrice to yield solid 50% sulfonated branched poly(p-hydroxystyrene), 35.5 g after drying in a vacuum oven at 60° C. Elemental analysis: C 55.46%, H 6.66%, N 6.17%, S 7.15%. A sample for stain blocker testing was prepared by dissolution of the above material (15.0 g) in deionized water (35 mL). This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Method 2. Test results are shown in Table 2.
Into a 500-mL round-bottom flask was added poly(p-Hydroxystyrene) (20.0 g, branched, Dupont Electronic Polymers LLP; Lot no: PB5-8007B; M.W. 4934, see Materials) and DMF (75 mL). To the resulting orange solution was added SO3.DMF (6.4 g). The reaction mixture was stirred and heated at 150° C. under a nitrogen atmosphere for 18 h. After cooling to room temperature, the solvent was removed in vacuo and the resulting thick oil stirred under diethyl ether (200 mL) for 30 min. The diethyl ether was decanted off and the procedure repeated thrice to give solid 25% sulfonated branched poly(p-hydroxystyrene), 32.8 g, after drying in a vacuum oven at 60° C. Elemental analysis: C 60.92%, H 6.64%, N 5.44%, S 4.42%. A sample for stain blocker testing was prepared by dissolution of the above material (15.0 g) in deionized water (35 mL). This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Method 2. Test results are shown in Table 2.
To a solution of poly(p-hydroxystyrene-tert-butylacrylate ester) (61:39 ratio, 25.0 g, 110.74 mmol; M.W 12,800; Lot No: 10020-51-FDP; from Dupont Electronic Polymers LLP, see Materials) in 1,4-dioxane (100 mL) was slowly added 2N hydrochloric acid (113.16 mL). The reaction mixture was heated at reflux for 19 h. After cooling reaction mixture to room temperature, the solvent was removed under vacuum to obtain a solid. To the solid was slurried with 250 mL water and transferred to a glass frit. The mixture was filtered and the collected solids were washed 3 times with 150 mL water to remove residual acid. The solids were dried in a vacuum oven at 50° C. overnight to give unsulfonated PHS acrylic acid polymer (21.36 g). 1H and 13C NMR showed removal of the t-butyl groups. A sample for testing was prepared by dissolving the above material (15 g) in deionized water (75 mL) and 1N NaOH (28 mL). This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2 and 4. Test results are shown in Table 2.
Into a 500-mL round bottom flask was added poly-p-hydroxystyrene-t-butylacrylate (20 g, 61:39 monomer ratio by weight, from Dupont Electronic Polymers LLP, Lot No. 10020-51-FDP, see Materials) and DMF (120 mL). To the resulting solution was added, portion wise, DMF.SO3 (1.52 g) and the resulting solution heated to 150° C. with stirring for 18 h. The reaction mixture was cooled to room temperature and the solvent removed in vacuo at 100° C. to give a brown foamy oil. The oil was added to diethylether (200 mL) and stirred for 30 min. Decanting the ether and repeating the procedure repeatedly until is solidified. The solid was dried under high vacuum to give 10% sulfonated poly-p-hydroxystyrene acrylic acid (61:39), 22.5 g. 1H and 13C NMR showed that the t-butyl group had been removed in the course of the sulfonation. Elemental analysis: C 53.66%, H 7.08%, N 6.53%, S 5.62%. A sample for stain blocker testing was prepared by dissolving the above polymer (15 g) in deionized water (70 mL) and 2N NaOH (14 mL). This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Method 2. Test results are shown in Table 2.
Example 6 was repeated except tetrahydrofuran was employed instead of 1,4-dioxane and the reaction mixture was refluxed for 20 hours. 1H NMR showed removal of the t-butyl group to yield unsulfonated PHS acrylic acid polymer. A sample for stain blocker testing was prepared by dissolving the above polymer (15 g) in deionized water (70 mL) and 2N NaOH (14 mL). This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2, 3, 4, 5, and 6. Test results are shown in Tables 2,3and4.
A solution of poly(p-hydroxystyrene-styrene-tert-butylacrylate ester)(60:20:20 ratio)(30.0 g, 0.250 mmol; DuPont Electronic Materials LLP, Lot No: TA4-6041B) in tetrahydrofuran(150 g), concentrated hydrochloric acid (9 g), and water (16 g) was refluxed for 20 hours. The solution was cooled and evaporated to dryness. The solid was washed with 3-100 ml portions of water and dried in a vacuum oven at 80° C. to yield unsulfonated PHS-styrene-acrylic acid polymer. 1H NMR showed removal of the t-butyl group. A sample for stain blocker testing was prepared by dissolving the above polymer (23 g) in deionized water (100 mL) and 10% NaOH (23 mL) to give a solution with 18.8% solids.
This solution was applied to carpet using Test method 1. The carpet was evaluated for stain resistance using test Methods 2, 3, 4, 5, and 6. Test results are shown in Tables 2,3 and 4.
Into a 250-mL round bottomed flask was added poly(-hydroxystyrene-t-butylacrylate) (31 g, , 60:40 monomer ratio by weight, from Dupont Electronic Technologies LLP, see Materials) and DMF(80 g). The solution was heated to 100° C. and purged subsurface with nitrogen for 0.5 hours. Then a DMF-SO3(11.5 g) slurry in DMF(20 g) was added over a 20 minute period. The solution was heated for 10 hours at 100° C. The solution was then cooled and the DMF removed in vacuo. The green oil was then washed with water(3-100 mL portions) to give 19.5 g of 8% sulfonated(poly-p-hydroxystyrene-acrylic acid). Elemental analysis: C 66.3%1, H 6.99%, N 1.21%, S, 1.10%. A sample for stain blocker testing was prepared by dispersing 10.0 g of the above polymer in deionized water(60 g) and 10% sodium hydroxide(10.0 g) and heating for one hour at 70° C. to give a 16.0 wt % solution. This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2, 4 and 6. Test results are shown in Tables 2 and 4.
Into a 250-mL round-bottomed flask was added poly(-hydroxystyrene-t-butylacrylate (31 g, 60:40 monomer ratio by weight, from Dupont Electronic Technologies LLP, see Materials) and DMF (90 g). The solution was heated to 100° C. and purged subsurface with nitrogen for 0.5 hours. Then a DMF-SO3(5.8 g) slurry in DMF (10 g) was added over a 20-minute period. The solution was heated for 20 hours at 100° C. The solution was then cooled and the DMF removed in vacuo. The green oil was then washed with water (3-100 mL portions) to give 23.7 g of 15% sulfonated(poly-p-hydroxystyrene-acrylic acid). Elemental analysis: C 62.5%1, H 6.65%, N 1.62%, S, 2.60%. A sample for stain blocker testing was prepared by dispersing 10.0 g of the above polymer in deionized water (60 g) and 10% sodium hydroxide(10.0 g) and heating for one hour at 70° C. to give a 16.6 wt % solution. This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2, 3, 4 and 6. Test results are shown in Tables 2 and 4.
Into a 250 mL round-bottomed flask was added poly(p-hydroxystyrene (20 g, from DuPont Electronic Polymers LLC) and dioxane(120 g). The solution was heated to 40° C. and stirred until the polymer was dissolved in solution. The DMF.SO3(24.5 g) complex was added over a 30-minute period. The temperature was increased to 85° C. and it was stirred for 24 hours. A dark brown oil precipitated. The solution was decanted off and the oil was washed with acetone(3-100 mL portions). The polymer was dried in an oven at 60° C. in vacuo. Elemental Analysis: S 7.25% best fits a 50% sulfonated poly(p-hydroxystyrene). A sample for stain blocker testing was prepared by dissolving the above polymer (20.0 g) in deionized water (150 mL) and 10% NaOH (20 mL) to give a solution of 11.0% solids. This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2, 3, 4, and 6. Test results are shown in Tables 2 and 4.
Into a 250-mL round-bottom flask was added poly(p-hydroxystyrene) (20 g, M.W. 8,000, Aldrich) and dimethyl formamide (DMF, 100 mL). To the resulting solution was added SO3.DMF(7.6 g). The reaction mixture was heated at 120° C. for 10 hours. After cooling to room temperature the solvent was removed on a rotary evaporator and then dried at 80° C. in vacuo to yield solid 31% sulfonated poly(p-hydroxystyrene), 31.0 g. Elemental analysis: S 4.77%. A sample for testing was prepared by adding the above solid (31 g) to deionized water (250 mL) and of 10% NaOH (12 mL) to give a solution with 11.1 wt % solids. This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2, 3, 4, and 6. Test results are shown in Tables 2 and 4.
Example 13 was repeated to yield 32% sulfonated poly(p-hydroxystyrene) 29.2 g. Elemental analysis: S 4.91%. A sample for stain blocker testing was prepared by dissolving the above polymer (10 g) in deionized water (50 mL) and 10% NaOH (8 mL). This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2, 4 and 6. Test results are shown in Table 2.
Into a 1-L round-bottomed flask was added poly(-hydroxystyrene-t-butylacrylate) (100.0 g, 60:40 monomer ratio by weight, from Dupont Electronic Technologies LLP, see Materials) and DMF(250 g). The solution was purged subsurface with nitrogen for 0.5 hours at room temperature. Then a DMF-SO3(30.6 g) slurry in DMF (30 g) was added over a 20-minute period. The solution was heated for 20 hours at 150° C. The solution was then cooled and the DMF removed in vacuo. The green oil was then washed with water (3-100 mL portions) to give 103 g of beige powder of 23% sulfonated(poly-p-hydroxystyrene-acrylic acid). Elemental analysis: C 55.63%, H 6.86%, N 3.81%, S 3.21%. A sample for stain blocker testing was prepared by dissolving the above polymer (75 g) in deionized water (250 mL) and 10% NaOH (75 mL) to give a solution with 19.4% solids. This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2, 3, 4, 5, and 6. Test results are shown in Tables 2, 3 and 4.
Into a 250-mL round-bottomed flask was added poly(-hydroxystyrene-styrene-t-butylacrylate) (30 g, 60:20:20 monomer ratio by weight, from Dupont Electronic Technologies LLP, see Materials) and DMF (100 g). The solution was purged subsurface with nitrogen for 0.5 hours at room temperature. Then a DMF-SO3(6.9 g) slurry in DMF (30 g) was added over a 20-minute period. The solution was heated for 20 hours at 150° C. The solution was then cooled and the DMF removed in vacuo. The orange oil was then washed with water (3-100 mL portions) to give 30.4 g of 18% sulfonated(poly-(p-hydroxystyrene-styrene-acrylic acid). Elemental analysis: C 69.5%1, H 7.18%, N 2.39%, S, 2.49%. A sample for stain blocker testing was prepared by dispersing 20.0 g of the above polymer in deionized water (90 g) and 10% sodium hydroxide(20.0 g) and heating for one hour at 70C to give a 19.3 wt % solution. This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2, 3, 4, 5, and 6. Test results are shown in Tables 2, 3 and 4.
Into a 1-L round-bottomed flask was added poly(-hydroxystyrene-t-butylacrylate) (93.0 g, 60:40 monomer ratio by weight, from Dupont Electronic Technologies LLP, see Materials) and DMF(240 g). The solution was purged subsurface with nitrogen for 0.5 hours at 100° C. Then a DMF-SO3(34.5 g) slurry in DMF(60 g) was added over a 15-minute period. The solution was heated for 20 hours at 100° C. The solution was then cooled and the DMF removed in vacuo. The green oil was then washed with water(3-100 mL portions) to give 64 g of beige powder of 25% sulfonated(poly-p-hydroxystyrene-acrylic acid). Elemental analysis: C 59.73, H 7.34, N 4.33, S 3.27%. A sample for stain blocker testing was prepared by dissolving the above polymer (64 g) in deionized water (350 mL) and 10% NaOH (60 mL) and heating to 70° C. to give a solution with 13.5% solids. This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Method 2, 3, and 4. Test results are shown in Tables 2, 3 and 4.
Comparative Example A was diluted and applied to carpet using Test Method 1 and tested using Test Methods 2, 3, 4, 5, and 6. Test results are shown in Tables 2, 3 and 4.
Into a 500-mL round-bottom flask was added poly(p-hydroxystyrene-t-butylacrylate) co-polymer (20 g, 61:39%, Dupont Electronic Polymers LLP, Lot No. 10020-51-FDP, see Materials) and DMF (120 mL). To the resulting solution was added SO3.DMF (15.19 g) and the resulting solution was heated at 150° C. with stirring for 18 h. The reaction mixture was cooled to room temperature and the solvent removed in vacuo to give a brown oil. The oil was added to diethyl ether (200 mL) and stirred for 30 min.; decanting the diethyl ether and repeating the procedure several times caused the polymer to solidify. The solid was dried under high vacuum to give the product, 100% sulfonated poly(p-hydroxystyrene-acrylic acid) (61:39), 36.7 g. 1H and 13C NMR showed that the t-butyl group had been removed in the course of the sulfonation. Elemental analysis: C 48.69%, H 6.0%, N 7.15%, S 8.29%. A sample for stain blocker testing was prepared by dissolving the above polymer (15 g) in deionized water (45 mL) and 1N NaOH (8.5 mL). This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Method 2. Test results are shown in Table 2.
Into a 500-mL round-bottom flask was added poly(p-hydroxystyrene) (20.0 g, branched, Dupont Electronic Polymers LLP; Lot no: PB5-8007B; M.W. 4934, see Materials) and DMF (110 mL). To the resulting orange solution was added SO3.DMF (25.53 g). The reaction mixture was stirred and heated at 150° C. under nitrogen atmosphere for 18h. After cooling to room temperature, the solvent was removed in vacuo and the resulting thick oil stirred under diethyl ether (200 mL) for 30 min. The diethyl ether was decanted off and the procedure repeated thrice to give solid product, 100% sulfonated branched poly(p-hydroxystyrene), 43.2 g, after drying in a vacuum oven at 60° C. Elemental analysis: C 47.34%, H 6.12%, N 7.44%, S 10.85%. A sample for stain blocker testing was prepared by dissolution of the above material (15.0 g) in deionized water (35 mL). This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Method 2. Test results are shown in Table 2.
Into a 250 mL round-bottomed flask was added poly(p-hydroxystyrene (20 g, from DuPont Electronic Polymers LLC) and dioxane(120 g). The solution was heated to 40° C. and stirred until the polymer was dissolved in solution. The DMF.SO3(24.5 g) was added over a 30-minute period. The temperature was increased to 85° C. and it was stirred for 24 hours. A dark brown oil precipitated. The solution was decanted off and the oil was washed with acetone(3-100 mL portions). The polymer was dried in an oven at 60° C. in vacuo to give an 86% sulfonated product. Elemental Analysis: S, 14.95%. A sample for stain blocker testing was prepared by dissolving the above polymer (20.0 g) in deionized water (100 mL) and 10% NaOH (42 mL) to give a solution of 19.8% solids. This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2, 4 and 6. Test results are shown in Tables 2 and 4.
Example 13 was repeated except twice the amount of DMF-SO3 adduct (15.0 g) was employed, yielding 63% sulfonated poly(p-hydroxystyrene). Elemental analysis: S 9.58%. A sample for stain blocker testing was prepared by dissolving the above polymer (43 g) in deionized water (150 mL) and 10% NaOH (20 mL) to yield a 12.1 weight % solution. This solution was applied to carpet using Test Method 1. The carpet was evaluated for stain resistance using Test Methods 2, 4, and 6. Test results are shown in Table 2.
The following notes apply to Tables 2, 3, and 4
(f) Different test sets are separated by heavy lines. Due to carpet sample variations, comparisons are made within test sets.
The results in Tables 2 and 4 demonstrated that both the sulfonated and unsulfonated p-hydroxystyrene polymer stain resists of the present invention block coffee and mustard to a greater extent than a commercial polycarboxylate stain resist (Comparative Example A). These examples of the present invention are also often comparable or better in durability and resistance to red dyes such as KOOL-AID, depending on the polymer and the extent of sulfonation. The less sulfonated polymers (<50%) of the present invention gave the best overall performance of blocking mustard and coffee. The heavily sulfonated Comparative Examples showed less desirable blocking with the coffee stain (Comparative Examples B, C, D, E), and with mustard stains (Comparative Examples D and E). The unsulfonated polymers of Examples 6, 8 and 9 also showed superior coffee and mustard blocking when compared to a commercial polycarboxylate (Comparative Example A). Example 8 also showed superior durability and resistance to staining with red dye (KOOL-AID) performance.
The data in Table 3 showed the sulfonated and unsulfonated p-hydroxystyrene polymers of the present invention also demonstrated superior UV light stability by Test Method 5 when compared to commercial polycarboxylate (Comparative Example A).
The results further demonstrated that the compositions of the present invention (see Example 2) have a better combination of properties. Example 2 was equal or to or better than Comparative Example A in resistance to red dye (KOOL-AID), durability, and light fastness, and much better in coffee stain blocking.