Silane-Terminated Polymer Composition Balancing Cure and Handling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing α-silane-terminated polymers with trimethoxysilyl end groups are highly reactive, making them difficult to handle and requiring expensive, highly reactive water scavengers, which are economically impractical for the adhesive and sealant market, and conventional water scavengers like vinyltrimethoxysilane are ineffective.
Innovation Solution
A crosslinkable composition containing a mixture of polymers with both α-trimethoxysilyl and conventional trimethoxysilyl groups, stabilized by conventional water scavengers such as vinyltrimethoxysilane, eliminating the need for expensive scavengers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If α-trimethoxysilyl-terminated polymers are used, then reactivity towards moisture is improved, but handling difficulty increases and cost increases due to expensive water scavengers
Solution Approach 1:
The invention segments the polymer population into two distinct groups: α-trimethoxysilyl-terminated polymers (providing high reactivity) and conventional trimethoxysilyl-terminated polymers (providing stability). This segmentation allows each polymer type to fulfill its specific function without the drawbacks of using only the highly reactive α-trimethoxysilyl polymers alone.
Solution Approach 2:
The invention changes the compositional parameter by controlling the ratio of α-trimethoxysilyl to conventional trimethoxysilyl polymers within specific ranges (5:95 to 50:50 by weight). This parameter optimization balances reactivity and stability, allowing the system to achieve fast curing while maintaining handling ease and eliminating the need for expensive water scavengers.
2Speed
If α-trimethoxysilyl-terminated polymers are used, then reactivity towards moisture is improved, but cost increases due to expensive water scavengers
Solution Approach 1:
The invention segments the polymer population into two distinct groups: α-trimethoxysilyl-terminated polymers (providing high reactivity) and conventional trimethoxysilyl-terminated polymers (providing stability). This segmentation allows each polymer type to fulfill its specific function without the drawbacks of using only the highly reactive α-trimethoxysilyl polymers alone.
Solution Approach 2:
The invention changes the compositional parameter by controlling the ratio of α-trimethoxysilyl to conventional trimethoxysilyl polymers within specific ranges (5:95 to 50:50 by weight). This parameter optimization balances reactivity and stability, allowing the system to achieve fast curing while maintaining handling ease and eliminating the need for expensive water scavengers.
3Ease of manufacture
If conventional water scavengers are used with α-trimethoxysilyl polymers, then cost is reduced, but effectiveness decreases due to insufficient water scavenging capacity
Solution Approach 1:
The invention segments the polymer population into two distinct groups: α-trimethoxysilyl-terminated polymers (providing high reactivity) and conventional trimethoxysilyl-terminated polymers (providing stability). This segmentation allows each polymer type to fulfill its specific function without the drawbacks of using only the highly reactive α-trimethoxysilyl polymers alone.
Solution Approach 2:
The invention changes the compositional parameter by controlling the ratio of α-trimethoxysilyl to conventional trimethoxysilyl polymers within specific ranges (5:95 to 50:50 by weight). This parameter optimization balances reactivity and stability, allowing the system to achieve fast curing while maintaining handling ease and eliminating the need for expensive water scavengers.
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 stable curing without the need for expensive water scavengers, enhancing handling and economic viability while maintaining high reactivity.
Implementation Method 1
Upon contact with water or atmospheric humidity, these alkoxysilane-terminated polymers are able to condense together at room temperature, releasing the alkoxy groups
Implementation Method 2
Water scavengers such as vinyltrimethoxysilane capture these traces of water by reacting with them themselves, thus completely or at least largely preventing premature condensation of the silane-terminated polymers
Data Source
AI summary
The invention relates to cross-linkable compositions containing (A) 100 parts by weight compounds of formula (I): Y−[(CR1 2)a−Si(OR)3]x, with the stipulation that, in component (A), in 5 to 60% of all units [(CR1 2)a−Si(OR)3] a is equal to 1 and in at least 5% of all compounds of formula (I) per molecule at least one a is equal to 1 and at least one a is a whole number from 2 to 10, (B) at least 0.1 parts by weight silanes selected from tetraethoxysilane and silanes of formula (II): R4-Si(CH3)b(OR2)3-b, and (C) at most 2 parts by weight one or more silanes of formula (III): X-CH2-SiR6 c(OR5)3-c, the groups and indices having the meaning specified in claim 1. The invention further relates to processes for the preparation thereof and to the use thereof as adhesives and sealants.