Carboxyl-Functional Organopolysiloxane Surface Treatment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organopolysiloxanes with two carboxyl groups per silicon atom face challenges in achieving high reactivity and satisfactory affinity with unctuous agents, particularly in surface treatment applications.
Innovation Solution
An organopolysiloxane with a specific compositional formula featuring terminal carboxyl groups and a balanced ratio of organic substituents, allowing for high reactivity and improved affinity with unctuous agents, is synthesized through an addition reaction and subsequent ring-opening process, followed by reaction with a base to replace the proton with a monovalent cation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If an organopolysiloxane with two carboxyl groups per silicon atom is prepared from a special organopolysiloxane having two terminal amino groups or a special organopolysiloxane having an amino group and a hydroxyl group, then the organopolysiloxane has two carboxyl groups per silicon atom, but the preparation process becomes complex and requires special starting materials
Solution Approach 1:
The patent changes the preparation method parameters by using conventional organopolysiloxanes with hydroxyl groups as starting materials and reacting them with dicarboxylic acid anhydrides under controlled conditions (molar ratios, temperature, time) to achieve the desired double carboxyl group structure without requiring special amino-group-containing starting materials
Solution Approach 2:
The patent creates a new preparation route that copies the successful methodology from single carboxyl group formation and extends it to double carboxyl group formation by using equivalent molar amounts of dicarboxylic acid anhydride, thereby simplifying the overall process
2Ease of manufacture
If an organopolysiloxane with two carboxyl groups per silicon atom is prepared using conventional methods, then the preparation is relatively easy, but the affinity with unctuous agents such as hydrocarbon unctuous agent is not satisfactory
Solution Approach 1:
The patent introduces methyl groups at specific positions (R5 and R6) adjacent to the carboxyl groups to create local hydrophobic regions that enhance affinity with unctuous agents, while maintaining the overall simplicity of the preparation process using conventional starting materials
Solution Approach 2:
The patent creates a composite structure where hydrophobic methyl groups and hydrophilic carboxyl groups coexist in close proximity, enabling the molecule to simultaneously interact with both unctuous agents and substrates through its carboxyl groups
3Reliability
If the ratio of carboxyl groups to organic substituents is increased to enhance reactivity, then the reactivity with substrates improves, but the viscosity increases making the material difficult to handle
Solution Approach 1:
The patent optimizes the molar ratio parameters of starting materials (organopolysiloxane to dicarboxylic acid anhydride) to achieve a balanced composition where sufficient carboxyl groups are present for high reactivity while the overall molecular weight and viscosity remain at manageable levels
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 resulting organopolysiloxane exhibits enhanced reactivity and affinity with unctuous agents, leading to improved dispersivity and surface treatment properties, particularly in applications involving powders like titanium dioxide and zinc oxide.
Implementation Method 1
subjecting an organohydrogenpolysiloxane having hydrogen atoms at the sites where R 2[0018]The addition reaction in the step (1) is preferably performed in the presence of a platinum or rhodium catalyst.
Implementation Method 2
reacting water with the organopolysiloxane having acid anhydride groups to thereby convert the acid anhydride groups into carboxyl groups
Implementation Method 3
reacting a carboxylic acid obtained in the step (2) with an organic or inorganic base, an organopolysiloxane with its proton being replaced with a monovalent cation can be prepared
Data Source
AI summary
An organopolysiloxane represented by the following average compositional formula (1): R1a R2b R3c SiO(4-a-b-c)/2 (1) wherein R1 is selected from the group consisting of C1-30 alkyl, C1-30 fluoroalkyl, C6-30 aryl, and C6-30 aralkyl groups, R2 is a group represented by the following formula (2), provided that R2 is bonded to at least one terminal end of the organopolysiloxane when c equals 0, R3 is a group represented by the following formula (3): wherein R2 is as defined above, each R8 is, independently, selected from the group consisting of C1-30 alkyl, C1-30 fluoroalkyl, C6-30 aryl, and C6-30 aralkyl groups, Q is CdH2d or an oxygen atom, wherein d is an integer of from 1 to 5, k is an integer of from 0 to 500, and h is an integer of from 0 to 3, a is a number of from 1.5 to 2.5, b is a number of from 0.001 to 1.5, and c is a number of from 0 to 1.5.