Silicone Rubber Composition Adhesion and Flow Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Hydrosilylation-curable silicone rubber compositions containing calcium carbonate powder tend to decrease cohesive failure when adhered to silicone rubber, and replacing calcium carbonate with quartz powder results in unwanted liquid dripping and reduced adhesion due to air bubble formation and improper application.
Innovation Solution
A silicone rubber composition comprising diorganopolysiloxane with alkenyl groups, quartz powder with a specific particle size, organopolysiloxane with silicon-bonded hydrogen atoms, calcium carbonate powder, and a hydrosilylation catalyst, optimized to improve adhesion and flow properties by controlling the ratio and properties of these components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If calcium carbonate powder is used in the silicone rubber composition, then adhesion to silicone rubber is improved, but cohesive failure factor decreases
Solution Approach 1:
The patent changes the particle size parameter of quartz powder to a specific range (0.01 to 3.0 μm) to optimize both adhesion and cohesive failure properties. This parameter adjustment allows the composition to achieve excellent adhesion to silicone rubber while maintaining high cohesive failure factor, resolving the contradiction between adhesion improvement and strength maintenance.
2Strength
If quartz powder is used to replace calcium carbonate powder, then cohesive failure factor is improved, but liquid dripping occurs during application
Solution Approach 1:
The patent optimizes the particle size parameter of quartz powder within the range of 0.01 to 3.0 μm and controls the ratio of quartz powder to calcium carbonate powder (5/100 to 100/5 by mass). This dual parameter control ensures that the composition maintains high cohesive failure factor while achieving proper flow properties that prevent liquid dripping during dispenser application.
Solution Approach 2:
The patent creates a composite filler system combining quartz powder and calcium carbonate powder in specific ratios rather than using a single filler type. This composite approach allows the composition to benefit from the high cohesive failure factor of quartz powder while the calcium carbonate powder contributes to maintaining good flow properties and preventing liquid dripping during application.
3Use of energy by moving object
If quartz powder is used in the composition, then adhesion force is improved, but air bubbles form and appearance is spoiled
Solution Approach 1:
The patent controls the particle size of quartz powder within the fine range of 0.01 to 3.0 μm and adjusts the quartz powder to calcium carbonate powder ratio. This parameter optimization ensures that the composition maintains strong adhesion force to silicone rubber while achieving uniform flow characteristics that prevent air bubble formation and ensure consistent, defect-free application.
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 excellent adhesion to silicone rubber with restricted liquid dripping during application, ensuring uniformity and improved physical characteristics, making it suitable for adhesive and sealing applications.
Implementation Method 1
a hydrosilylation-curable silicone rubber composition that contains quartz powder and calcium carbonate powder
Data Source
AI summary
A silicone rubber composition comprising: 100 parts by mass of a diorganopolysiloxane (A) having on average at least two alkenyl groups in one molecule; 5 to 100 parts by mass of a quartz powder (B) with an average particle size in the range of 0.01 to 3.0 ?m; an organopolysiloxane (C) having on average of at least two silicon-bonded hydrogen atoms in one molecule {the mole ratio of silicon-bonded hydrogen atoms contained in this component to alkenyl groups of component (A) is in the range of 0.5 to 5}; 5 to 100 parts by mass of a calcium carbonate powder (D); and a hydrosilylation catalyst (E) (in an amount sufficient for accelerating the curing of the silicone composition of the present invention).