Silane-terminated Polymer Adhesive for Thermoplastic Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current adhesive compositions based on silane-terminated polymers face challenges in achieving strong adhesion on difficult substrates like polyolefins and bituminous materials without the need for pretreatments, and they often have high volatile organic carbon (VOC) levels and slow adhesion build-up.
Innovation Solution
A one-component adhesive composition combining 0.5-2.5 wt.% of monomeric or oligomeric aminofunctional alkoxysilanes with specific nitrogen content, along with 15-35 wt.% of polymeric plasticizer, improves adhesion on non-pretreated surfaces, including polyolefins and bituminous substrates, while maintaining low VOC levels and facilitating fast adhesion build-up.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional adhesive compositions based on silane-terminated polymers are used, then general adhesion properties are maintained, but adhesion on difficult substrates like polyolefins and bituminous materials is insufficient
Solution Approach 1:
The patent modifies the chemical composition parameters of the adhesive by introducing specific compounds (polybasic acid, polyacid anhydride, and silane-modified polymer) in defined proportions. This parameter change enables the adhesive to achieve strong bonding on difficult substrates like polyolefins and bituminous materials while maintaining versatility across different substrate types.
Solution Approach 2:
The invention creates a composite adhesive system combining multiple components: polybasic acid, polyacid anhydride, and silane-modified polymer. This composite formulation synergistically improves adhesion on challenging substrates while preserving broad substrate compatibility, resolving the contradiction between specialized bonding and general versatility.
2Strength
If adhesive compositions are formulated for strong bonding, then adhesion strength is improved, but volatile organic carbon (VOC) levels increase
Solution Approach 1:
The patent adjusts the chemical composition parameters by selecting specific compounds with lower VOC content and optimizing their proportions. The formulation achieves strong adhesion through the synergistic action of polybasic acid, polyacid anhydride, and silane-modified polymer while maintaining low VOC emissions, thus resolving the contradiction between bonding strength and environmental compatibility.
3Speed
If adhesive compositions are designed for fast adhesion build-up, then curing speed is improved, but adhesion strength may be compromised
Solution Approach 1:
The invention optimizes the chemical parameters by selecting compounds with appropriate reactivity and optimizing their concentrations. The polybasic acid, polyacid anhydride, and silane-modified polymer are formulated in specific proportions that enable fast adhesion build-up through rapid crosslinking while ensuring sufficient final bond strength, resolving the contradiction between curing speed and bonding strength.
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 excellent adhesion on a variety of substrates, including those traditionally difficult to bond, with rapid adhesion build-up and low VOC emissions, enhancing its efficiency and environmental sustainability.
Implementation Method 1
They are cured via crosslinking reactions of the silane groups, which are hydrolyzed under the influence of moisture, condense with one another as silanol groups and in so doing form siloxane bonds.
Implementation Method 2
They are cured via crosslinking reactions of the silane groups, which are hydrolyzed under the influence of moisture, condense with one another as silanol groups and in so doing form siloxane bonds.
Implementation Method 3
the combination of between 0.5 and 2.5 wt.-%, based on the total composition, of at least one monomeric or oligomeric aminofunctional alkoxysilane S1 with a nitrogen content of between 4.5 and 14.5 wt.-%, based on the total weight of S1 and between 0.5 and 2.5 wt.-%, based on the total composition, of at least one oligomeric aminofunctional alkoxysilane S2 with a nitrogen content of between 15 and 20 wt.-%, based on the total weight of S2
Data Source
AI summary
An adhesive composition, including at least polymer containing silane groups, between 15 and 35 wt.-% of at least one polymeric plasiticzer, between 0.5 and 2.5 wt.-% of at least one monomeric or oligomeric aminofunctional alkoxysilane S1 with a nitrogen content of between 4.5 and 14.5 wt.-%, and between 0.5 and 2.5 wt.-% of at least one oligomeric aminofunctional alkoxysilane S2 with a nitrogen content of between 15 and 20 wt.-%. The adhesive composition is particularly suitable to seal or bond thermoplastic substrates, such as polyolefins or bituminous materials, and shows fast adhesion build-up and low volatile organic carbon (VOC).