WO2001030128A1

WO2001030128A1 - Soil sequestering article

Info

Publication number: WO2001030128A1
Application number: PCT/US2000/028087
Authority: WO
Inventors: Donald L. Schmidt; Robert D. Mussell; Gene D. Rose
Original assignee: The Dow Chemical Company
Priority date: 1999-10-26
Filing date: 2000-10-11
Publication date: 2001-05-03
Also published as: WO2001030128A8; AR026238A1

Abstract

An article impregnated with a cationic modifier that serves to sequester dispersed and emulsified soils from a surface is described. The cationic modifier is a) a C14-C32 linear or branched alkyl or alkenyl tri-C1-C6 alkylammonium salt; or b) a polymer which has pendant or incorporated quaternary ammonium salt groups and which contains less than 50 mole equivalents of groups formed from the polymerization of acrylamide; or c) a combination of (a) and (b). The modified article of the present invention provides an efficient means of cleaning surfaces, particularly surfaces contaminated with oil or soil that is hydrophobic and anionic.

Description

SOIL SEQUESTERING ARTICLE

The present invention is a substrate containing impregnated cationic groups that serve to sequester dispersed and emulsified soils from a surface. Most natural soils are anionic. A common method for cleaning a soiled surface is to spray the surface with a cleaning formulation then wiping the surface with an article such as absorbent towel to remove the dispersed or emulsified soil. Generally, not all of the soil is transferred to the towel in a single spray and wipe, therefore necessitating several sprays and wipes to achieve an acceptably clean surface. Even with multiple wipes, some cleaning formulations remain on the surface, resulting in streaks. It would therefore be an advance in the art to have a towel that could clean a soiled surface more efficiently with less streaking.

The present invention is a cationically modified article for wiping surfaces which article comprises an absorbent substrate of fibrous or cellular material impregnated with a cationic modifier which is a) a Cι₄-C₃₂ linear or branched alkyl or alkenyl, tri-Cι-C₆-alkylammonium salt; or b) a polymer which has pendant or incorporated quaternary ammonium salt groups and which contains less than 50 mole equivalents of groups formed from the polymerization of acrylamide: or c) a combination of (a) and (b).

The cationically modified article of the present invention provides an efficient means of cleaning surfaces, particularly surfaces fouled with oil or hydrophobic soil.

The article of the present invention is an absorbent substrate of fibrous or cellular material, preferably a flexible fibrous material, that is impregnated with a Cι₄-C₃₂ branched or linear alkyl or alkenyl tri-Cι-C₆-alkyl- or hydroxyalkylammonium salt, or a polymer that contains pendant or incorporated quaternary ammonium salt groups or a combination thereof. The word impregnated is used herein to mean physically or chemically bound to the article. The Cι₄-C₃₂ branched or linear alkyl or alkenyl tri-Cι-C₆-alkyl or hydroxy alkylammonium salt is represented by the formula:

where R₂ is C₁₄-C₃₂ branched or linear alkyl or alkenyl, and each R₂ is independently Cι-C₆-alkyl or hydroxy alkyl. Preferably, Ri is ₆-C₂₄ linear alkyl or alkenyl, more preferably C₁₈-C₂₂ linear alkyl or alkenyl; preferably, each R₂ is independently methyl, ethyl, or 2-hydroxyethyl. more preferably methyl or ethyl, and most preferably methyl. Examples of commercially available long chain alkyl or alkenyl tri-Cι-C₆ alkyl ammonium salts include ARQUAD™ 16-26 surfactant (Ci₆H ₃-trimethlyammonium chloride, a trademark of Akzo Nobel Chemicals, Inc., Chicago, IL), ARQUAD 18-50 surfactant (C₁₈H₃₇-trimethlyammonium chloride), and KEMAMINE™ Q2983-C surfactant (C₂₂H₄₄- trimethlyammonium chloride, a trademark of Witco Corp., Greenwich, CT).

A cationic polymer containing pendant quaternary ammonium salt groups can be prepared by the reaction of an ethylenically unsaturated quaternary ammonium salt and a nonionic ethylenically unsaturated monomer which is preferably an alkyl acrylate, or an alkyl methacrylate, or an alkenyl aromatic hydrocarbon, or a combination thereof. Preferred ethylenically unsaturated quaternary ammonium salts include ethylenically unsaturated trialkylammonium salts such as vinylbenzyl tri-Cι-C₄-alkylammonium chloride or bromide; trialkylammoniumalkyl acrylates or methacrylates such as 2-[(methacryloyloxy)ethyl]- trimethylammonium chloride and N,N-diethyl-N-methyl-2-[(l-oxo-2-propenyl)oxy] ethanaminium methyl sulfate (Chem. Abstracts Reg. No. 45076-54-8); and trialkylammoniumalkyl acrylamides such as N,N,N-trimethyl-3-[(2-methyl-l-oxo-2- propenyl)amino]-l-propanaminium chloride (Chem. Abstracts Reg. No. 51441-64-6) and N,N-dimethyl-N-[3-[(2-methyl-l-oxo-2-propenyl)amino]propyl]-benzenemethaminium chloride (Chem. Abstracts Reg. No. 122988-32-3). A preferred polymerizable quaternary ammonium salt is 2-[(methacryloyloxy)ethyl]trimethylammonium chloride.

Preferred nonionic monomers include acrylates such as methyl acrylate, ethyl acrylate, butyl acrylate, and lauryl acrylate; methacrylates such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, and lauryl methacrylate; and alkenyl aromatic hydrocarbons such as Cι-C₄ alkyl- or alkenyl- substituted styrenes, preferably styrene, α-methylstyrene, vinyltoluene, and vinylbenzyl chloride. More preferred nonionic monomers include methyl methacrylate, ethyl methacrylate, butyl methacrylate, and lauryl methacrylate, and combinations thereof. Preferably the mole-to-mole ratio of the groups formed from the polymerization of the ethylenically unsaturated nonionic monomer to the quaternary ammonium salt groups is not greater than 96:4, more preferably not greater than 90: 10, and most preferably not greater than 80:20, and preferably not less than 20:80, more preferably not less than 40:60, and most preferably not less than 50:50.

Suitable cationic polymers may also be prepared by incorporating quaternary ammonium salt groups into the backbone of the polymer. For example, a dialkyl amine such as dimethyl amine can be reacted with an epihalohydrin such as epichlorohydrin to form a linear polyquat with the quatemized nitrogen on the polymer backbone. This type of polyquat is known as ionene. Other suitable cationic polymers include cationically modified natural products such as cationically modified cellulosic polymers or starch.

If a polymer containing quaternary ammonium salts is used, it is preferred that the polymer contains less than 50 mole equivalents, more preferably less than 40 mole equivalents, more preferably less than 25 mole equivalents, more preferably less than 10 mole equivalents, and most preferably 0 mole equivalents of groups formed from the polymerization of acrylamide. It is also possible, and may be advantageous, to incorporate carboxyl groups to the backbone of the polymer so long as the mole-to-mole ratio of cationic groups to carboxyl groups is greater than 1:1. Preferably, the ratio of quaternary ammonium salt groups to carboxyl groups is not less than 2:1, more preferably not less than 5:1, and most preferably not less than 20: 1.

The polymer or C₁₄-C₃₂ branched or linear alkyl or alkenyl tri-C C₆ alkylammonium salt can be applied to the substrate as either a solution or a dispersion, preferably a solution. A solution is advantageously prepared by reacting the monomers in an aqueous-based solvent for the consequently formed polymer. The aqueous based solvent preferably includes water and a water-compatible solvent in sufficient amounts to dissolve the polymer. More preferably the aqueous-based solvent includes water and a polar protic solvent. The polar protic solvent is preferably a -C₄ alcohol, and more preferably ethanol or 1-propanol, and most preferably 1-propanol.

If it is desirable to prepare a stable aqueous dispersion of the polymer, such a dispersion can be prepared by any suitable means, such as is described in U.S. Patent 5,674,934, column 6, lines 46-56 and 62-67, and column 7, lines 1-9, which teaching is incorporated herein by reference.

The cationically modified article can be advantageously prepared by spraying a dilute solution or dispersion containing the long chain alkyl or alkenyl tri-Cι-C₆- alkylammonium salt or the polymer containing the pendant or incorporated quaternary ammonium salt groups or combinations thereof, then drying the towel by any suitable means, such as air drying or oven drying. The amount cationic charge per substrate is sufficient to improve the cleaning properties of the substrate. For example, if the substrate is a 26 x 28 cm² Kleenex Brand VIVA™ paper towel (trademark of Kimberly-Clark Tissue Co., Neenah, WI, 0.07 cm thick), the amount of the cationic modifier is preferably not less than 0.02 meq/towel (meq refers to milliequivalents), and more preferably not less than 0.05 meq/towel, and preferably not more than 1.0 meq/towel, more preferably not more than 0.5 meq/towel, and most preferably not more than 0.3 meq/ towel. Thus, the concentration of the cationic modifier is preferably not less than 3 x 10^"5 meq/cm² towel, more preferably not less than 7 x 10^"5 meq/cm² towel; and preferably not more than 1.5 x 10^"3 meq/cm² towel, more preferably not more than 7 x 10^ meq/cm² towel, and most preferably not more than 4 x 10^{^}* meq/cm² towel.

The cationically modified article of the present invention provides an efficient means of transferring dirt, particularly anionic or hydrophobic soil or oil from a surface to a substrate.

The following examples are for illustrative purposes only and are not intended to limit the scope of this invention.

Examples 1-3 - Cleaning Motor Oil with a Towel Impregnated with a Cationic Surfactant

A NIVA™ paper towel (26 x 28 cm² surface area, 0.07 cm thick) is treated by spraying 5.1 g of a 0.6 weight percent aqueous solution of a cationic surfactant listed in

Table I. The total dry weight of the surfactant on each towel is about 0.03 g. The towel was air-dried overnight at ambient temperature.

Six drops (0.025 g/drop) of used black diesel motor oil is applied to a 12" x 12" (30.5 x 30.5 cm²) glass plate, one drop at each of four corners, and one drop in the middle of the plate. The oil was spread uniformly across the surface with a wiper. The soiled surface is then sprayed with WTNDEX™ cleaner (a trademark of S.C. Johnson Wax, Racine, WI), then wiped back and forth 12 times (back is 1, forth is 2, etc.) with the treated paper towel that is folded to make a 7-cm x 7-cm square pad. The surface is re-soiled, sprayed, then wiped again with the same side of the folded paper towel. The performance of the first and second cleaning is assigned a rating of 2 to 6, with 2 being equivalent to the cleaning performance of wiping with an untreated towel in the same way. A towel that cleans sufficiently well to yield an essentially non-streak surface is given a rating of 6. The relative cleaning performance of the modified VINA towels is shown in Table I. The surfactant is of the type R-Ν⁺(CH₃)₃ Cl^". The surfactant used in Example 1 is ARQUAD™ 16-26 surfactant (a trademark of Akzo Nobel Chemicals Inc., Chicago, IL); in Example 2, ARQUAD™ 18-50 surfactant; and in Example 3, KEMIMINE™ Q2983-C surfactant (a trademark of Witco Corp., Greenwich, CT). The abbreviations eq weight and meq/towel refer to equivalent weight and milliequivalents of charge per towel, respectively.

Table I - Relative Cleaning Performance of Towels Modified with Long Chain Alkyl Trimethylammonium Chloride Surfactants

Examples 4-6 - Relative Cleaning Performance at a Constant Concentration of Charge

In the following examples, each towel is modified with about 5.1 g of 0.018 N solutions of the alkyl trimethylammonium chloride cationic surfactant used in Examples 1- 3. Thus, the charge per towel is kept constant. In these examples, the performance of a single cleaning is shown in Table II.

Table II - Relative Cleaning Performance of Towels Modified with Long Chain Alkyl

Trimethylammonium Chloride Surfactants at a Constant Charge Concentration

Examples 7-10 - Relative Cleaning Performance of Various Concentrations of C₂₂H₄₄N⁺(CH₃)₃C1^" (KEMANINE Q2983-C surfactant)

In the following examples, the amount of the KEM AMINE surfactant applied to the towel is varied and the performance measured in three cleanings.

Table III - Relative Cleaning Performance of Towels Modified with Various Concentrations

Examples 11-15 - Cleaning Motor Oil with a Towel Impregnated with a Polymeric Cationic Surfactant

In the following examples, each towel is modified with about 5.1 g of a 0.06 weight aqueous percent solution of a polymer (about 0.03 g of solids) containing units formed from the polymerization of 2-((methacryloyloxy)ethyl) trimethylammonium chloride (Quat) and methyl methacrylate (MMA). The polymerizations are carried out at between 60°C and 80°C under nitrogen in a stirred reactor (1 L). Four liquid streams are simultaneously and continuously added over five hours to the reactor, which initially contains 10 weight percent of the total monomers to be reacted and 60 g of 1-propanol. One stream contains MMA, a second contains Quat, a third contains 2.0 g of VAZO 52 initiator and 75 g of 1-propanol, and a fourth contains 45 g of 1-propanol and 45 g of water. After addition is completed, the reaction is kept at 80°C for an additional hour. Table II shows the relationship between molar equivalent ratios of Quat and MMA and the cleaning performance.

Table IV - Relative Cleaning Performance of Towels Modified with Copolymers of MMA and Quat

Examples 16-20 - Cleaning Performance of Towels Modified with Copolymers of MMA, LMA, and Quat

In these examples, each towel is modified with about 5.1 g of a 0.06 weight aqueous percent solution of a polymer (about 0.03 g of solids) containing units formed from the polymerization of MMA, lauryl methacrylate (LMA), and Quat. The polymer is prepared substantially as described in Examples 11-15, with the LMA being added to the same stream containing the MMA. The performance of the towel modified with surfactant containing LMA units is shown in Table V.

Table V - Performance of Towel Modified with Polymeric Surfactant Containing MMA, LMA, and Quat

Claims

CLAIMS:

1. A cationically modified article for wiping surfaces comprising an absorbent substrate of fibrous or cellular material impregnated with a cationic modifier which is a) a -C₃₂ linear or branched alkyl or alkenyl, tri-Cι-C₆-alkylammonium salt; or b) a polymer which has pendant or incorporated quaternary ammonium salt groups and which contains less than 50 mole equivalents of groups formed from the polymerization of acrylamide, or a combination thereof; or c) a combination of (a) and (b).

2. The modified article of Claim 1 which comprises an absorbent substrate of fibrous material impregnated with a C₁₄-C₃₂ linear or branched alkyl or alkenyl trimethylammonium salt, a -C₃₂ linear or branched alkyl or alkenyl triethylammonium salt, or Ci₄-C₃₂ linear or branched alkyl or alkenyl tri-2-hydroxyethylammonium salt.

3. The modified article of either of Claims 1 or 2 wherein the cationic modifier is a Ci₆-C₂ linear alkyl or alkenyl trimethylammonium salt and wherein the concentration of the alkyl or alkenyl trimethylammonium salt on the absorbent substrate is not less than 3 x 10^"5 meq/cm² and not more than 7 x 10^"4 meq/cm².

4. The modified article of either of Claims 2 or 3 wherein the Cι₄-C₃₂ linear or branched alkyl or alkenyl trimethylammonium salt is a Cι₈-C₂₂ linear alkyl or alkenyl trimethylammonium salt and wherein the concentration of the C₁₈-C₂₂ linear alkyl or alkenyl trimethylammonium salt on the surface of the substrate is not less than 7 x 10^"5 meq/cm² and not more than 4 x 10^"4 meq/cm².

5. The modified article of any of Claims 1-4 wherein the cationic modifier is a C₁₈ or a C₂₂ linear alkyl or alkenyl trimethylammonium chloride or a combination thereof.

6. The modified article of Claim 1 wherein the absorbent substrate is impregnated with a polymer which has pendant quaternary ammonium salt groups and which contains less than 40 mole equivalents of groups formed from the polymerization of acrylamide.

7. The modified article of Claim 6 wherein the polymer contains structural units formed from the polymerization of an ethylenically unsaturated quaternary ammonium salt, an alkyl methacrylate, and less than 25 mole equivalents of groups formed from the polymerization of acrylamide, and wherein the mole-to-mole ratio of the structural units formed from the polymerization of the alkyl methacrylate to the quaternary ammonium salt groups is not greater than 96:4 and not less than 20:80.

8. The modified article of either of Claims 6 or 7 which contains less than 10 mole equivalents of groups formed from the polymerization of acrylamide wherein the ethylenically unsaturated quaternary ammonium salt is

2-[(methacryloyloxy)ethyl]trimethylammonium chloride and the alkyl methacrylate is methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, or lauryl methacrylate, or a combination thereof and wherein the mole-to-mole ratio of the structural units formed from the polymerization of the nonionic monomer to the quaternary ammonium salt groups is not greater than 90:10 and not less than 40:60.

9. The modified article of Claim 8 which contains 0 mole equivalents of groups formed from the polymerization of acrylamide wherein the alkyl methacrylate is methyl methacrylate or lauryl methacrylate, or a combination thereof and wherein the mole-to-mole ratio of the structural units formed from the polymerization of the nonionic monomer to the quaternary ammonium salt groups is not greater than 80:20 and not less than 50:50.