Self-Crosslinking Polymer Network for Absorbent Textiles

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing processes for producing absorbent textile materials face challenges such as incomplete cross-linking, high material loss, low free absorbency, safety concerns due to residual chemicals, and ecological unsustainability, particularly in the use of synthetic polymeric absorbents and cross-linking agents.

Innovation Solution

A process involving an aqueous polymeric composition with a high concentration of both synthetic and natural polymers, deposited uniformly on textile materials or textured yarn, which undergo self-crosslinking during thermal treatment without the need for non-polymeric crosslinking agents, forming a continuous polymer network that enhances water absorbency and biodegradability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If self-crosslinking synthetic polymers are used to create absorbent textile materials, then the free absorbency is improved, but more than 10% of end product is lost during extraction of monomers, initiators and organic solvents residue

Engineering Contradiction:
Improvefree absorbencyVSAvoidmaterial loss
Core Design Contradiction:
ReliabilityVSLoss of substance

Solution Approach 1:

The invention changes the chemical composition parameters by using polymers with pendant groups capable of self-crosslinking (carboxylic acid, sulfonic acid, phosphoric acid groups) and eliminates the need for external crosslinking agents, monomers, and initiators. This parameter change resolves the contradiction by achieving crosslinking without the harmful residues that cause material loss during extraction.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention extracts and removes the harmful components (monomers, initiators, organic solvents, and non-polymeric crosslinking agents) from the system by using self-crosslinking polymers that contain all necessary functional groups within the polymer structure itself, eliminating the need for separate extraction steps and reducing material loss.

Inventive Principle:
Principle #2Taking out (Extraction)

2Reliability

If cross-linking is performed during copolymerization or after polymerization with subsequent neutralization, then water swellable polyelectrolytes are formed, but these cannot be cross-linked in situ as a coating on a substrate or as a flexible film

Engineering Contradiction:
Improvewater swellabilityVSAvoidin situ cross-linking capability
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The invention incorporates preliminary action by pre-equipping the polymer chains with pendant groups (carboxylic acid, sulfonic acid, or phosphoric acid groups) that are capable of self-crosslinking. This preliminary preparation allows the polymer to crosslink in situ on substrates or films without requiring subsequent neutralization or additional crosslinking agents, resolving the contradiction between water swellability and in situ cross-linking capability.

Inventive Principle:
Principle #10Preliminary action

3Reliability

If traditional synthetic polymeric absorbents are used, then high absorbency is achieved, but ecological sustainability is compromised due to biodegradability issues

Engineering Contradiction:
ImproveabsorbencyVSAvoidecological unsustainability
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The invention creates composite material properties by combining the high absorbency characteristics of synthetic polymers with the biodegradability of natural polymers. The crosslinked network structure maintains the absorbent functionality while the natural polymer component enables biodegradation, resolving the contradiction between absorbency and ecological sustainability.

Inventive Principle:
Principle #40Composite materials

4Manufacturing precision

If non-polymeric crosslinking agents are used to crosslink polymers, then cross-linking efficiency is improved, but safety concerns arise due to residual chemicals

Engineering Contradiction:
Improvecross-linking efficiencyVSAvoidsafety concerns
Core Design Contradiction:
Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

The invention applies self-service by enabling the polymer chains to crosslink themselves through their own pendant groups (carboxylic acid, sulfonic acid, or phosphoric acid groups) without requiring external non-polymeric crosslinking agents. This self-crosslinking mechanism maintains crosslinking efficiency while eliminating safety concerns related to residual chemical agents.

Inventive Principle:
Principle #25Self-service

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 resulting multi-layer absorbent products exhibit significantly improved water absorbency and biodegradability, reducing material loss and safety hazards while being more environmentally friendly, suitable for various applications including hygiene products and agricultural crop protection.

Implementation Method 1

which undergo self-crosslinking during thermal treatment without the need for non-polymeric crosslinking agents, forming a continuous polymer network

Methodology Applied
Scientific EffectSelf-crosslinking: Chemical Bonding

Implementation Method 2

The resulting multi-layer absorbent products exhibit significantly improved water absorbency

Methodology Applied
Scientific EffectAbsorption: Absorption (physical)

Implementation Method 3

deposited uniformly on textile materials or textured yarn, which undergo self-crosslinking during thermal treatment

Methodology Applied
Scientific EffectThermal treatment: Heating

Data Source

PatentEP4106513B1Multi-layer absorbent product and process for preparing absorbent layer
Publication Date: 2023.12.20 POLYGREEN LTD
  • EP4106513B1 patent drawingFigure 1~2
  • EP4106513B1 patent drawingFigure 3~4(3)
  • EP4106513B1 patent drawingFigure 5A~5B

AI summary

A multi-layer absorbent product is provided that includes a first layer that is either liquid permeable or liquid impermeable and a layer of a treated nonwoven, woven or knitted textile material or a treated textured plastic yarn. The layer of textured plastic yarn or of nonwoven, woven or knitted textile material has uniformly spaced deposits of a natural polymer crosslinked to a synthetic polymer in the absence of non-polymeric crosslinking agent, where each of the deposits is a continuous polymer network that covers the textile or plastic underneath the deposit and interpenetrates the network of textile fibers or of plastic pores acting as a scaffold to interconnect the polymer network with the fiber network or with the network of plastic pore walls. A process for preparing the layer of textile material or of textured plastic yarn with uniformly spaced deposits is also provided.