High Purity Monoalkyltin Stabilizers for PVC
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current tin-based stabilizers for chlorine-containing polymers, such as PVC, contain toxic di- and tri-alkyltin compounds, posing toxicity issues, and existing methods for producing high purity mono-alkyltin compounds are inefficient due to the co-production of di- and tri-alkyltin by-products.
Innovation Solution
Development of high purity mono-alkyltin trihalides that are converted into mono-alkyltin derivatives, using a process involving hydrostannylation and reaction with a compound in the presence of a base, to produce compositions with minimal di- and tri-alkyltin content, suitable for use as stabilizers and catalysts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional tin-based stabilizers containing mixtures of mono- and di-alkyltin compounds are used, then thermal stability and color retention properties are improved, but toxicity increases due to di- and tri-alkyltin compound content
Solution Approach 1:
The patent extracts and removes di- and tri-alkyltin compounds from the stabilizer composition through selective chemical reactions. The process converts di- and tri-alkyltin compounds into mono-alkyltin compounds or other non-toxic derivatives, effectively extracting the harmful components while retaining the beneficial thermal stability properties.
Solution Approach 2:
The patent changes the compositional parameters of the stabilizer by controlling the purity of mono-alkyltin compounds to greater than 97 wt%, and preferably greater than 99 wt%. This parameter change from conventional mixture compositions to high-purity compositions resolves the contradiction by eliminating toxic components while maintaining effectiveness.
2Manufacturing precision
If existing methods for producing high purity mono-alkyltin compounds are used, then purity is improved, but di- and tri-alkyltin by-products are still co-produced in significant quantities
Solution Approach 1:
The patent converts the harmful by-products (di- and tri-alkyltin compounds) into beneficial products (mono-alkyltin compounds). Through selective chemical reactions, the process transforms unwanted toxic by-products into the desired high-purity mono-alkyltin compound, turning a manufacturing disadvantage into an advantage.
Solution Approach 2:
The patent discards the conventional approach that accepts di- and tri-alkyltin by-products and instead recovers them by converting them into mono-alkyltin compounds through chemical reactions. This recovery process eliminates waste while improving product purity and reducing toxicity.
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 yields high purity mono-alkyltin compounds that provide remarkable thermal stability and color retention properties to chlorine-containing polymers, reducing toxicity and improving industrial attractiveness.
Implementation Method 1
high purity mono-alkyltin trihalides can be converted to other mono-alkyltin derivatives
Implementation Method 2
using a process involving hydrostannylation and reaction with a compound in the presence of a base
Data Source
AI summary
The present invention relates to high purity monoalkyltin compounds, more specifically to alkyltin compound compositions containing monoalkyltin as major compound, and minor quantities of di- and/or trialkyltin compounds. The present invention also relates to the preparation processes of such high purity monoalkyltin compounds, as well as to the uses of said monoalkyltin compounds as chlorine-containing polymer-stabilizers, glass coating chemicals and catalysts, as well as articles comprising at least one polymer matrix and a high purity monoalkyltin compound.