Thickened compositions and method for prepn. of same

Thickening composition and preparation method thereof

The present invention relates to a thickened peroxygen composition, and more specifically to a thickened aqueous alkaline hydrogen peroxide composition, and a method for producing the same.

In recent years, there has been increasing interest in using peroxygen compositions, especially hydrogen peroxide compositions, to replace halogen-containing disinfectants and/or bleaching agents. Much attention has been focused on the use of alkaline hydrogen peroxide compositions because such compositions are known to have superior bleaching performance compared to acidic hydrogen peroxide compositions.

Disinfecting and bleaching compositions, although not specifically for civilian use, are often used to disinfect non-level surfaces. Therefore, it is generally required that such compositions be thickened in order to, for example, reduce the rate at which the composition flows down the surface, thereby increasing the contact time with the composition.

Many thickeners used in common alkaline systems, such as xanthan gum and cellulose-based thickeners, are not suitable for hydrogen peroxide because they are degraded by oxidation and thus rapidly lose their thickening ability. An alternative thickening system recommended by AK20 in European Patent Application 0265979 is a quaternary ammonium compound and a short-chain alkyl aryl sulfonate such as sodium xylene sulfonate. Unfortunately, since quaternary ammonium compounds generally exhibit poor biodegradability, they have a compacting effect on environmental ground. In addition, the quaternary ammonium compound plus short-chain alkyl aryl sulfonate system usually exhibits high viscoelasticity and has undesirable flow characteristics. To a certain extent, this problem can be avoided or improved by adding perfume. However, in some applications In, do not want to add spices.

An object of the present invention is to provide thickened aqueous neutral or alkaline hydrogen peroxide compositions to avoid the problems of quaternary ammonium-based systems.

Another object of the present invention is to provide a method for producing a thickened aqueous neutral or alkaline hydrogen peroxide composition that avoids the problems of quaternary ammonium-based systems.

According to one aspect of the present invention, there is provided a neutral or alkaline thickened aqueous hydrogen peroxide composition, which is characterized in that the composition contains an effective amount of thickening: i) a type containing pendant carboxyl groups and The general formula is A polymer of the polyethylene backbone of the pendant group of OR, where m is a positive integer, n is 0 or a positive integer, X and Y are each selected from hydrogen, methyl, and ethyl, and R contains 8 or more carbon atoms Hydrophobic group; and ii) one or more selected from ethoxylated alcohols, alkylbenzene sulfonates containing 10 or more carbon atoms, alkyl sulfates containing 6 or more carbon atoms, alcohols Surfactant for ether sulfate, α-thioester and alkyl glucoside.

According to the second aspect of the present invention, there is provided a method for producing a neutral or alkaline thickened aqueous hydrogen peroxide composition, characterized in that an effective amount of thickening is added to the aqueous hydrogen peroxide solution: i) a Contains pendant carboxyl groups and the general formula is The polymer of the polyethylene backbone of the pendant group of OR, where m is a positive integer, n is 0 or a positive integer, X and Y are each selected from hydrogen, methyl, and ethyl, and R contains 8 or more carbon atoms Hydrophobic group and ii) one or more selected from ethoxylated alcohols, alkylbenzene sulfonates containing 10 or more carbon atoms, alkyl sulfates and alkyl groups containing 6 or more carbon atoms Surfactant for glucoside, and adjust the pH of hydrogen peroxide to neutral or alkaline pH.

The polymer used in the composition and method of the present invention contains a polyethylene backbone. Such a main chain is usually produced by polymerization of ethylenically unsaturated compounds to which saturated carbon atoms are attached. Except for the pendant carboxylic acid group and the general formula is In addition to the pendant OR groups, the polymer may contain pendant alkyl groups, especially short chain alkyl groups such as methyl or ethyl.

The pendant carboxyl group can be directly attached to the polyethylene main chain, or can be separated from the main chain by a suitable linking group such as a saturated hydrocarbon chain. The carboxyl group can exist as a free carboxylic acid group, but due to the pH of the composition, the carboxyl group is mostly in the form of a salt.

The general formula is The pendant group of OR can be directly connected to the main chain of polyethylene, or it can be connected to the main chain through a suitable linking group. Said suitable linking group is clear to those skilled in the art, and in many cases it will be selected from saturated hydrocarbon groups, carbonyl groups and amide groups. The linking group preferably contains 1 to 4 carbon atoms. In this general formula, m represents a positive integer, usually 2 or greater, often greater than 10, more often greater than 20, but not greater than 100. In this general formula, n represents 0 or a positive integer. n is usually 0, if it is not 0, n is often smaller than m. R represents a hydrophobic group containing at least 8 carbon atoms. R can be a linear, branched or cyclic group, and can be optionally substituted with an alkylaryl group or an arylalkyl group. R does not contain more than 24 carbon atoms, preferably less than 18 carbon atoms.

Particularly preferred polymers are those sold by Allied Colloids Co., Ltd. under the trademarks "Rheovis CR", "Rheovis CRX" and "Rheovis CR3" in August 1993. It is generally believed that the thickening effect of these polymers together with surfactants is due to the general formula The combination of the side group of OR and the surfactant micelle is also attributed to the swelling properties of the polymer caused by the side group carboxyl group.

The concentration of the polymer in the composition of the invention can be varied within a wide range, depending on, for example, the required viscosity. The concentration is usually in the range of about 0.1% w/w to about 10% w/w, and more often in the range of about 0.5% w/w to 5% w/w.

The surfactant used in the composition and method of the present invention with any of the above-mentioned polymers is selected from ethoxylated alcohols, alkylbenzene sulfonates having 10 or more carbon atoms, and 6 or more Alkyl sulfates and alkyl glucosides of carbon atoms. Mixtures of two or more surfactants can be used, especially mixtures of nonionic surfactants and anionic surfactants. When using a nonionic surfactant with a low HLB value, it is particularly desirable to use a mixture of surfactants. Such low HLB surface-giving agents generally have poor solubility in water and may result in the formation of turbid solutions. In addition to the application of surfactant mixtures that can help overcome this problem, they also provide other benefits, such as improved cleaning or decontamination capabilities.

Suitable ethoxylated alcohols include ethoxylated alkylphenols, ethoxylated secondary alcohols, and ethoxylated linear or branched primary alcohols. The most preferred ethoxylated alcohols are ethoxylated linear primary alcohols. Suitable ethoxylated alcohols include ethoxylated alcohols having from about 8 to about 22 carbon atoms in the alkyl moiety, usually from about 9 to about 18 carbon atoms. The number of ethoxy groups in ethoxylated alcohols is usually 2 or more, more often 3 to about 30, and preferably about 4 to 16. In some embodiments, when the ethoxylated alcohol contains 6-9 ethoxy groups, good results are obtained. The ethoxylated alcohol can be end-capped with a low molecular weight alkyl or aryl group such as methyl, ethyl, isopropyl, t-butyl or benzyl, however, it is preferably not end-capped.

Suitable alkylbenzene sulfonates include linear and branched chain alkylbenzene sulfonates, with linear alkylbenzene sulfonates being preferred. The alkyl moiety preferably contains 6-18 carbon atoms, and more preferably contains 10-14 carbon atoms. The most preferred alkylbenzene sulfonate is dodecylbenzene sulfonate.

Suitable alkyl sulfates include linear and branched chain alkyl sulfates. Examples of suitable alkyl sulfates include sodium 2-ethylhexyl sulfate and sodium lauryl sulfate. A more suitable type of alkyl sulfate is alkyl ether sulfate, in which the sulfate group is bonded to the alkyl group via one or more, for example, 2-6 ethoxy groups.

The alkyl glucoside used in the present invention satisfies the general formula RO-(G)n, wherein R represents an alkyl group, G represents a glucoside moiety, and n represents a positive integer. R can be produced from natural products or synthetically, and usually contains 8-18 carbon atoms. In many suitable alkyl glucosides, n is 1-5.

The concentration of surfactant in the composition of the present invention is generally greater than about 0.1% w/w, more often greater than about 0.25% w/w, but not greater than about 10% w/w. The surfactant concentration is preferably about 0.5% to 5% w/w.

The weight ratio of polymer to surfactant in the composition of the present invention can be selected within a wide range, depending on the properties of the composition required. In many cases, the weight ratio of polymer to surfactant is selected in the range of about 0.1:1 to 10:1, usually about 0.25:1 to 7.5:1, and more often about 0.4:1 to about 5. :1. In some embodiments, good results have been obtained using a weight ratio of polymer to surfactant of 0.5:1 to 3:1.

The composition of the present invention can contain hydrogen peroxide in a very wide concentration range. However, in many implementations, the concentration of hydrogen peroxide is not less than about 1% w/w and not more than about 35% w/w, and is generally selected from about 3% w/w to about 20% w/w.

The composition of the present invention can be produced by diluting a concentrated aqueous hydrogen peroxide solution. However, alternative sources of hydrogen peroxide that can be used include persalts such as sodium percarbonate, sodium perborate monohydrate and tetrahydrate, and additional compounds such as those that are at least soluble in the composition to some degree but also form particulate residues. Carbamide peroxide.

The composition of the present invention has a neutral or alkaline pH. In the present invention, the term neutral pH refers to a pH of 6 or greater. The pH of the composition is generally not greater than about 11, usually in the range of about 7.2 to about 10, especially about 7.5 to about 9.5.

The composition of the present invention can be produced in a wide range of viscosities, from relatively free-flowing to gel. The amount of thickening system used is generally sufficient to produce an initial viscosity greater than about 50 cps, and often greater than about 100 cps. In many cases, the composition has an initial viscosity from about 200 cps to about 5000 cps. In some cases of the present invention, especially when the surfactant used contains an ethoxylated alcohol, a thickening system is selected such that the viscosity is initially low, but will increase with the storage time, for example, from 1 day to 1 day. 20 days or longer, such as 4 or 5 days to 10 days, and the viscosity increases. In some cases, as the storage composition reaches a higher viscosity, the composition is relatively easy to handle, such as mixing and packaging.

In addition to the above-mentioned components, the composition may contain one or more additional components, usually selected from hydrogen peroxide stabilizers, buffers, dyes and perfumes. Particularly suitable stabilizers include amino polyphosphonic acids and their salts, and are generally applied at about 0.01%, preferably about 0.1% to about 3% by weight of the composition. The preferred stabilizer is cyclohexyl-1,2-diaminotetramethylenephosphonic acid and its salts. The composition may also contain additional stabilizers, which can at least partially dilute the stabilized concentrated hydrogen peroxide solution. Examples of such additional stabilizers include phosphates and stannates. The amount of buffering agent should be able to maintain the composition at the required pH value. Preferably the buffering agent includes sodium benzoate.

The composition of the present invention can be prepared by adding the required components to an appropriate container and stirring, for example, mechanical stirring. The composition is usually prepared at ambient temperature, for example 15 to about 30°C. Generally, hydrogen peroxide is commercially available as a relatively concentrated acidic aqueous solution. In order to thereby obtain the composition of the present invention, it is usually necessary to dilute and adjust the pH. Preferably, the dilution is performed before adjusting the pH. Generally, pH adjustment including the addition of a base such as sodium hydroxide can be performed before or after the addition of other components. However, preferably, the pH adjustment is performed after adding other components.

The general situation of the present invention is described above, and its specific implementation is described in more detail in the following examples. Unless otherwise specified, all percentages in the composition are w/w.

Example 128.46g 35% hydrogen peroxide aqueous solution containing 1.2% cyclohexyl-1,2-diaminotetramethylenephosphonic acid (CDTMP) was diluted with 140g demineralized water. Under stirring, 4g of the product produced by AlliedColloids Co., Ltd. in August 1993, which contains a carboxyl-containing polymer with the trademark "Rheovis CRX", and 2g of the product with the trademark "Synperonic A9", produced by CargoFleet Chemicals with C13-C15 alkane The base part and 9 ethoxy groups of ethoxylated alcohol surfactant, 3g sodium benzoate and 0.1g brand "LK30524", perfume produced by BushBoake Allen Co., Ltd. Add sodium hydroxide solution (12% aqueous solution) to adjust the pH to 9.5. Then, the composition was diluted to 200 g with additional demineralized water.

The initial viscosity of the resulting composition (Brookfield RVT, Spindle 2 at 50 rpm) was 100 cps. After storing for 20 days at 32°C and 80% relative humidity, the composition retained 87% of its hydrogen peroxide and a viscosity of 252 cps.

Example 2 The process of Example 1 was repeated, except that the product with the trademark "Rheovis CRX" produced by 4g Allied Colloids Co., Ltd. was replaced with the trademark "Rheovis CR3" produced by the company.

The initial viscosity of the resulting composition (Brookfield RVT, Spindle 2 at 50 rpm) was 216 cps. After 28 days of storage at 32°C and 80% relative humidity, the hydrogen peroxide in the composition retained 88% and the viscosity was 372 cps.

Example 3 The process of Example 1 was repeated, except that the product manufactured by Allied Colloids Co., Ltd. with the trademark "Rheovis CR" was used instead of the product with the trademark "Rheovis CRX".

The initial viscosity of the resulting composition (Brookfield RVT, Spindle 2 at 50 rpm) was 192 cps. After 28 days of storage at 32°C and 80% relative humidity, the composition retained 98% of its hydrogen peroxide and had a viscosity of 88 cps.

Example 4 The composition prepared by the method of Example 1, containing 21% hydrogen peroxide, 0.72% CDTMP, 5% trademark "Rheovis CRX" polymer produced by Allied Colloids Co., Ltd., 1% trademark "Synperonic 91 /8" An ethoxylated alcohol surfactant with C9 alkyl moiety and 8 ethoxy groups, produced by Cargo Fleet Chemicals Co., Ltd., has a pH of 6-7.

The initial viscosity of the composition (Brookfield RVT, Spindle 2, at 50 rpm) was 6000 cps. After 14 days of storage at 32°C and 80% relative humidity, the composition retains its 100% hydrogen peroxide and a viscosity of 6000 cps.

Example 5 The process of Example 1 was repeated, except that 1.8 g of alkyl glucoside (33% by weight effective) purchased from Rohm and Haas in the United Kingdom was used instead of ethoxylated alcohol. Sodium benzoate was not used, but perfume was used.

The initial viscosity of the resulting composition (Brookfield RVT, Spindle 2, at 50 rpm) was 1500 cps. After 4 days of storage at ambient temperature (approximately 20°C), the viscosity of the composition increased to 3200 cps.

Example 6

Example 5 was repeated, except that 0.2% sodium lauryl sulfate was used as the surfactant.

The initial viscosity of the resulting composition (Brookfield RVT, Spindle 2, at 50 rpm) was 1200 cps. After 5 days of storage at ambient temperature (about 20°C), the viscosity of the composition increased to 3800 cps.

Example 7 Repeat Example 5, except that 0.7% of the dodecylbenzene sulfonate solution (30% effective by weight) produced by the British Cargo Fleet Chemical Company under the trademark "Caflon NAS 30" was used as the surfactant.

The initial viscosity of the resulting composition (Brookfield RVT, Spindle 2, at 50 rpm) was 1100 cps. After 5 days of storage at ambient temperature (about 20°C), the viscosity increased to 4200 cps.

Example 8 Example 5 was repeated, except that 0.7% of the ethoxylated alcohol of Example 1, ie "Synperonic A9" was used as the surfactant.

The initial viscosity of the resulting composition (Brookfield RVT, Spendle 2, at 50 rpm) was 1500 cps. After 5 days of storage at ambient temperature (about 20°C), the viscosity increased to 2500 cps.

Comparative Example 9 repeats Example 1 but does not use the ethoxylated alcohol surfactant.

The viscosity of the resulting composition is only 24 cps.

Comparative Example 10 Example 1 was repeated, except that 2 g of sorbitan monooleate sold in the UK market under the trademark "Span 80" was used instead of the ethoxylated alcohol surfactant.

The resulting composition is cloudy and its viscosity is only 24 cps.

Comparative Example 11 repeats Example 1 except that the polymer "Rheovis CRX" is not used.

The viscosity of the resulting composition was too low to be measured with a Brookfield RVT viscometer.

The results of Examples 1 to 4 show that the thickening composition of the present invention not only has good viscosity, but also has good hydrogen peroxide stability in a wide range of viscosity and hydrogen peroxide concentration. The results of Examples 5-8 show that the different ranges of surfactants of the present invention can be used to produce different viscosities, and the thickening system can be selected to produce a composition with a lower initial viscosity but an increase in viscosity with storage time. The results of Comparative Examples 9 and 11 show that no thickening component, that is, the polymer or surfactant selected in the present invention, the thickening effect is significantly reduced. The results of Comparative Example 10 show that when the surfactant selected by the present invention is replaced by a non-inventive surfactant, the viscosity thickening of the obtained composition is not beyond the viscosity thickening of the composition of Comparative Example 9.