Polymer Structured Aqueous Detergent Viscosity Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Concentrated aqueous detergent compositions face challenges in maintaining high pour viscosity while providing suspending rheology, as certain polymers used to enhance detergency reduce pour viscosity, and existing copolymers either fail to increase pour viscosity sufficiently or require additional rheology modifying materials.

Innovation Solution

A polymer structured aqueous detergent composition incorporating a specific copolymer formed by addition polymerization of ethylenically unsaturated diacids, monoacidic monomers, and surfmers, which increases pour viscosity and provides the necessary rheology for suspending particles, counteracting the viscosity-reducing effects of other polymers like ethoxylated polyethylene imine and polyester soil release polymers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If concentrated aqueous detergent compositions use polymers like ethoxylated polyethylene imine and polyester soil release polymers to enhance detergency, then cleaning performance is improved, but pour viscosity decreases

Engineering Contradiction:
Improvecleaning performanceVSAvoidpour viscosity
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent combines multiple polymer types in a composite system: a first copolymer (acrylic/methacrylic acid with alkyl ester and crosslinker) for viscosity enhancement, a second copolymer (acrylic/methacrylic acid with alkyl ester and surfmer) for detergency, along with ethoxylated polyethylene imine and polyester soil release polymers. This composite approach allows the viscosity-enhancing first copolymer to counterbalance the viscosity-reducing effect of the cleaning polymers, maintaining overall pour viscosity while achieving enhanced cleaning performance.

Inventive Principle:
Principle #40Composite materials

2Stability of the object's composition

If existing copolymers are used to increase pour viscosity, then viscosity is improved, but additional rheology modifying materials are required

Engineering Contradiction:
Improvepour viscosityVSAvoidnumber of rheology modifiers
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The first copolymer (comprising acrylic/methacrylic acid, alkyl ester, and crosslinker) is designed to perform multiple functions simultaneously: it increases pour viscosity, provides suspending rheology for particles, and counteracts the viscosity-reducing effects of other polymers in the formulation. This multi-functional design eliminates the need for separate rheology modifying materials, reducing formulation complexity while achieving the desired rheological properties.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Reliability

If acrylate copolymers are used at high levels to provide suspending rheology, then particle suspension is improved, but pour viscosity becomes excessively high

Engineering Contradiction:
Improveparticle suspensionVSAvoidpour viscosity
Core Design Contradiction:
ReliabilityVSStability of the object's composition

Solution Approach 1:

The patent applies different copolymers with specialized functions at different concentrations: the first copolymer (acrylic/methacrylic acid with alkyl ester and crosslinker) is used specifically for viscosity control and suspending rheology at optimized levels, while the second copolymer (acrylic/methacrylic acid with alkyl ester and surfmer) handles detergency. This localized functional assignment allows each copolymer to perform its specific role efficiently without one polymer needing to compensate for another's limitations, achieving particle suspension without excessive pour viscosity.

Inventive Principle:
Principle #3Local quality

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The composition achieves increased pour viscosities while maintaining suitable rheology for suspending and spraying, effectively counteracting the viscosity-reducing effects of other polymers, ensuring stable particle suspension and improved user experience.

Implementation Method 1

a copolymer formed by the addition polymerisation of: (A) 0.1 to 5 wt% of a first monomer consisting of an ethylenically unsaturated diacid of formula (I)

Methodology Applied
Scientific EffectAddition polymerization: Photopolymerisation

Implementation Method 2

these types of acrylates copolymers give an undesirably high pour viscosity if they are used at a high enough level to provide a suspending rheology

Methodology Applied
Scientific EffectShear thinning: Shear Thinning

Implementation Method 3

the liquid should have rheology that provides a yield stress (also known as critical stress) so that the particles remain stably suspended and dispersed

Methodology Applied
Scientific EffectYield stress rheology: Bingham Plastic

Data Source

PatentEP2925843B1Polymer structured aqueous detergent compositions
Publication Date: 2016.08.31 UNILEVER PLC
  • EP2925843B1 patent drawingFigure 1~2
  • EP2925843B1 patent drawingFigure 3~4
  • EP2925843B1 patent drawingFigure 5

AI summary

An aqueous polymer structured detergent liquid composition comprising: (i) a surfactant system comprising surfactant and alkaline material present as surfactant salts and/or as free base, (ii) optionally, 0.01 wt% or more suspended particles, (iii) optionally, 3 wt% or more polymer that reduces the composition viscosity at 20 s-1, and (iv) at least 0.05 wt% of a suspending system comprising copolymer formed by the addition polymerisation of: (A) 0.1 to 5 wt% of a first monomer consisting of an ethylenically unsaturated diacid of formula (I): HOOC-CR1=CR2-COOH or an unsaturated cyclic anhydride precursor of such an ethylenically unsaturated diacid, the anhydride having formula (II) where R1 and R2 are individually selected from H, C1-C3 alkyl, phenyl, chlorine and bromine; (B) 15 to 60 wt% of a second ethylenically unsaturated monoacidic monomer consisting of (meth)acrylic acid; (C) 30 to 70 wt% of a third ethylenically unsaturated monomer consisting of C1-C8 alkyl ester of (meth)acrylic acid; (D) 1 to 25 wt%, of a fourth ethylenically unsaturated monomer, consisting of surfmer of formula (III) wherein each R3 and R4 are each independently selected from H, methyl, -C(=O)OH, or -C(=O)OR5; R5 is a C1-C30 alkyl; T is -CH2C(=O)O-, -C(=O)O-, -O-, -CH2O-, -NHC(=O)NH-, -C(=O)NH-, -Ar-(CE2)2-NHC(=O)O-, -Ar-(CE2)2-NHC(=O)NH-, or -CH2CH2NHC(=O)-; Ar is divalent aryl; E is H or methyl; z is 0 or 1; k is an integer in the range of 0 to 30; and m is 0 or 1; with the proviso that when k is 0, m is 0, and when k is in the range of 1 to 30; m is 1; (R6O)n is polyoxyalkylene, which is a homopolymer, a random copolymer, or a block copolymer of C2-C4-oxyalkylene units, wherein R6 is C2H4, C3H6, C4H8, or a mixture thereof, and n is an integer in the range of 5 to 250;Y is -R6O-, -R6-, -C(=O)-, -C(=O)NH-, =R6NHC(=O)NH-, or -C(=O)NHC(=O)-; and R7 is substituted or unsubstituted alkyl selected from the group consisting of C8-C40 linear alkyl, C8-C40 branched alkyl, C8-C40 carbocyclic alkyl, C2-C40 alkyl-substituted, phenyl, aryl-substituted C2- C40 alkyl, and C8-C80 complex ester; wherein the R7 alkyl group optionally comprises one or more substituents selected from the group consisting of hydroxy, alkoxy, and halogen; and (E) 0.005 to 5 wt%, of a cross linking agent, for introducing branching and controlling molecular weight, the cross linking monomer comprising polyfunctional units carrying multiple reactive functionalisation groups selected from the group consisting of vinyl, allyl and functional mixtures thereof.