Hydrophilic Polysiloxane Elastomer Water Uptake Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Siloxane elastomers used in cosmetics face challenges in achieving high water uptake while being compatible with organic solvents, and there is a desire to minimize or eliminate pendant polyalkoxy groups due to their exposure and instability.
Innovation Solution
A siloxane elastomer with a crosslinked structure, featuring aminofunctional pendant groups on polysiloxane backbone polymers, which achieves high water uptake and compatibility with organic solvents without pendant poly(alkylene oxide) groups, using crosslinkers like primary organic dienes and divinyl siloxanes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If pendant polyalkoxy groups are used to increase water uptake, then hydrophilicity is improved, but stability and cosmetic safety are worsened due to exposure and lability of pendant groups
Solution Approach 1:
The patent extracts the problematic pendant polyalkoxy groups from the elastomer structure while retaining the essential water uptake functionality through internal polyalkoxy sequences within the polymer backbone. This removes the exposed, labile pendant groups that cause stability issues while preserving the hydrophilic character needed for water absorption.
Solution Approach 2:
The patent creates a composite elastomer structure combining siloxane backbone with internal polyalkoxy sequences, forming a new material that achieves both hydrophilicity and stability. The composite structure allows the polyalkoxy groups to be embedded within the polymer matrix rather than exposed as pendant groups, resolving the contradiction between water uptake and stability.
2Quantity of substance
If pendant polyalkoxy groups are used to achieve high water uptake, then hydrophilicity is improved, but compatibility with organic solvents is worsened
Solution Approach 1:
The patent removes pendant polyalkoxy groups that interfere with organic solvent compatibility while maintaining water uptake capability through internal polyalkoxy sequences. This extraction of problematic groups resolves the incompatibility issue with organic solvents used in cosmetic formulations.
Solution Approach 2:
The patent applies local quality by positioning polyalkoxy groups specifically within the polymer backbone rather than as external pendant groups. This localized placement allows the elastomer to maintain hydrophilicity where needed while preserving compatibility with organic solvents in the overall structure.
3Reliability
If polyalkoxy groups are eliminated to improve stability, then reliability is improved, but water uptake capability is worsened
Solution Approach 1:
The patent transitions from two-dimensional pendant groups attached to the backbone to a three-dimensional integrated structure where polyalkoxy sequences are embedded within the polymer chain itself. This dimensional change allows the elastomer to maintain stability by eliminating exposed pendant groups while preserving water uptake through internal hydrophilic pathways.
Solution Approach 2:
The patent creates a composite elastomer structure that integrates polyalkoxy sequences within the siloxane backbone, forming a new material that simultaneously achieves high stability and maintained water uptake capability without relying on pendant groups.
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 elastomer demonstrates at least 50 weight-percent water uptake and compatibility with key organic solvents, maintaining performance without pendant polyalkoxy groups, enhancing its stability and cosmetic application efficacy.
Implementation Method 1
certain aminofunctional pendant groups when present on crosslinked polysiloxanes provide the desired properties identified for siloxane elastomers, even in an absence of poly(alkylene oxide) pendant groups
Implementation Method 2
The elastomer of the present invention is useful in making cosmetic formulations of the present invention... compatible with key organic solvents used in the cosmetic industry
Data Source
AI summary
An elastomer has the general structure of:where: subscript a is 50-500, b is 1-10, c is 2-30, R1 has the structure:—CH2(CH2)nO(CH2)pCH(OH)(CH2)qNR2R2′where n, p and q are each independently 1-5 and R2 and R2′ are independently selected from alkyl and hydroxyalkyl groups having 1-5 carbon atoms; where X is a crosslinker remnant bound to a siloxane unit corresponding to subscript c of a siloxane backbone polymer in addition to the one shown so that the crosslinker remnant in each occurrence is a reaction product with two siloxane backbone polymers, wherein the crosslinker is selected from a group consisting of primary organic dienes, divinyl siloxane and polyoxyalkylenes wherein at least two X components correspond to crosslinker remnants connecting the same two siloxane backbone polymers.