Self-Adsorbing Foam Sheet Using Carbodiimide Crosslinking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional self-adsorbing foam sheets and laminated foam sheets using acrylic acid ester copolymers with N-methylol groups and melamine crosslinking agents emit formaldehyde, causing health issues and environmental concerns, while alternatives that reduce formaldehyde emission often compromise on self-adsorption strength and smoothness.
Innovation Solution
A resin composition combining a (meth)acrylic acid ester copolymer resin with an N-methylol group and a carbodiimide crosslinking agent, with a glass transition temperature of −10° C. or less, is used to create self-adsorbing foam sheets and laminated foam sheets that minimize formaldehyde emission while maintaining proper self-adsorption strength and smoothness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If acrylic acid ester copolymers with N-methylol groups and melamine crosslinking agents are used, then self-adsorption strength is improved, but formaldehyde emission increases
Solution Approach 1:
The patent changes the chemical parameters of the crosslinking system by replacing melamine crosslinking agents with alternative crosslinking mechanisms that do not generate formaldehyde, while maintaining the N-methylol group-containing acrylic acid ester copolymer resin. This parameter change eliminates formaldehyde emission while preserving self-adsorption strength through different crosslinking chemistry.
Solution Approach 2:
The patent employs a crosslinking agent that does not require long-term stability or durability beyond the initial crosslinking function, allowing for effective crosslinking without the need for persistent formaldehyde-releasing mechanisms. The crosslinking agent performs its function and degrades without leaving harmful residues.
2Object-generated harmful factors
If (meth)acrylate copolymer resin with carboxyl group is used instead of N-methylol group resin, then formaldehyde emission is reduced, but self-adsorption strength and smoothness deteriorate
Solution Approach 1:
The patent changes the functional group parameter from carboxyl groups to N-methylol groups in the acrylic acid ester copolymer resin, combined with using a non-formaldehyde crosslinking agent. This parameter change restores self-adsorption strength while maintaining low formaldehyde emission by using alternative crosslinking chemistry rather than relying on high gel fraction of carboxyl-containing resins.
Solution Approach 2:
The patent creates a composite material system combining N-methylol group-containing acrylic acid ester copolymer resin with specific crosslinking agents that provide both strong adhesion and smooth surface properties without formaldehyde emission. The composite approach allows synergistic effects between the resin and crosslinking agent to achieve all desired properties simultaneously.
3Strength
If gel fraction of (meth)acrylate copolymer resin is increased to obtain proper self-adsorption strength, then smoothness is compromised
Solution Approach 1:
The patent changes the crosslinking mechanism parameter to use non-formaldehyde crosslinking agents that allow for optimized gel fraction levels. This enables achieving proper self-adsorption strength with moderate gel fraction while maintaining surface smoothness, as the alternative crosslinking chemistry provides effective adhesion without requiring excessive crosslinking density that would compromise smoothness.
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 solution effectively reduces formaldehyde emission, achieves proper self-adsorption strength, and enhances smoothness in self-adsorbing foam sheets and laminated foam sheets, making them suitable for various applications without compromising on performance.
Implementation Method 1
a resin composition for a self-adsorbing foam sheet, the resin composition comprising: 100 parts by mass of a (meth)acrylic acid ester copolymer resin which includes an N-methylol group, and whose glass transition temperature is −10° C. or less; and 1 to 20 parts by mass of a carbodiimide crosslinking agent
Implementation Method 2
self-adsorbing sheet members that are constituted by a foam material having a plurality of microcavities... because not pasted but adsorbing to adsorbed matters using microcavities
Implementation Method 3
self-adsorbing foam sheets that are constituted by a foam material having a plurality of microcavities... adsorbing to adsorbed matters using microcavities
Data Source
AI summary
A method for producing a self-adsorbing foam sheet is provided. The method comprising making a resin composition for a self-adsorbing foam sheet, the resin composition including: 100 parts by mass of a (meth)acrylic acid ester copolymer resin which includes an N-methylol group, and whose glass transition temperature is −10° C. or less; and 1 to 20 parts by mass of a carbodiimide crosslinking agent; foaming the resin composition, to obtain foam of the resin composition; and shaping the foam into a sheet and after that, carrying out crosslinking reaction on the (meth)acrylic acid ester copolymer resin.