SiOC-Bonded Polyether Siloxanes for Low-Odor PU Foams
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need to improve the production of polyurethane (PU) foams in terms of product quality, specifically to reduce odor and enhance ageing resistance, while also minimizing aldehyde emissions such as formaldehyde, acetaldehyde, and propionaldehyde.
Innovation Solution
A process for producing PU foams using SiOC-bonded polyether siloxanes with branching in the siloxane moiety, prepared from branched siloxanes bearing acetoxy groups, is employed. This involves reacting polyol and isocyanate components in the presence of catalysts and blowing agents with the SiOC-bonded polyether siloxanes, which are added in sufficient amounts to comprise 0.0001% to 10% by weight of the finished foam.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional polyols and isocyanates are used to produce PU foams, then the foam production process is simple and cost-effective, but the foams exhibit high odor and poor ageing resistance
Solution Approach 1:
The invention changes the chemical composition parameters by introducing SiOC-bonded polyether siloxanes with specific branching structures into the polyol component. This parameter change modifies the foam's chemical structure to reduce odor and improve ageing resistance simultaneously.
Solution Approach 2:
The invention uses composite materials by combining conventional polyols with SiOC-bonded polyether siloxanes in a hybrid formulation. This composite approach allows the foam to inherit beneficial properties from both components, achieving low odor and high ageing resistance.
2Reliability
If stabilizers are added to reduce odor and improve ageing resistance, then product quality improves, but the manufacturing process becomes more complex
Solution Approach 1:
The invention merges the functions of odor reduction and ageing resistance improvement into a single component (SiOC-bonded polyether siloxane). This eliminates the need for separate stabilizer additives and simplifies the manufacturing process while achieving multiple quality improvements simultaneously.
3Object-generated harmful factors
If conventional foam formulations are used, then production cost is low, but aldehyde emissions are high
Solution Approach 1:
The invention changes the chemical parameters by using SiOC-bonded polyether siloxanes with controlled branching and specific molecular structures. This parameter optimization reduces aldehyde emissions while maintaining cost-effectiveness through efficient use of the special polyol component.
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 process results in low-odor, ageing-resistant PU foams with reduced aldehyde emissions, as demonstrated by olfactory testing and compression set measurements, and improved foam properties such as porosity and density.
Implementation Method 1
SiOC-bonded polyether siloxanes having branching in the siloxane moiety
Implementation Method 2
one or more catalysts that catalyse the isocyanate-polyol and/or isocyanate-water reactions
Implementation Method 3
one or more chemical or physical blowing agents
Data Source
AI summary
Process for producing PU foams by reacting at least one polyol component with at least one isocyanate component in the presence of one or more catalysts that catalyse the isocyanate-polyol and/or isocyanate-water reactions and/or isocyanate trimerization, and optionally one or more chemical or physical blowing agents, with use of SiOC-bonded polyether siloxanes having branching in the siloxane moiety, prepared from branched siloxanes bearing acetoxy groups, wherein a sufficient amount of the SiOC-bonded polyether siloxane having branching in the siloxane moiety is added that the proportion by mass of this polyether siloxane (e) based on the finished PU foam is from 0.0001% to 10% by weight.