Curable Organopolysiloxane Composition for LED Packaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing curable organopolysiloxane compositions for packaging materials of electronic components, such as light emitting diodes, face issues with high viscosity, poor adhesive properties, sticky surfaces, and yellowing due to nonreactive residues during the curing process, which affect their heat resistance and mechanical strength.
Innovation Solution
A curable composition comprising an organopolysiloxane with at least two silicon-bonded alkenyl groups, a branched organopolysiloxane with a silicon-bonded alkenyl group, and an organopolysiloxane capped with H, along with a catalyst, which eliminates low molecular weight residue issues and enhances heat resistance, transmittance, and refractive index, allowing for a quick curing process with adjustable properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional curable organopolysiloxane compositions are used, then heat resistance and transparency are achieved, but high viscosity and poor adhesive properties occur
Solution Approach 1:
The patent modifies the chemical structure of the organopolysiloxane by introducing specific siloxane units with different compositions and ratios. By adjusting the molar ratios of various siloxane units (e.g., D3, D4, D5, D6 units) and controlling the content of specific structural units, the viscosity is reduced while maintaining heat resistance. The patent specifies precise compositional ranges to achieve the optimal balance between流动性 and thermal stability.
Solution Approach 2:
The patent creates a composite organopolysiloxane structure by combining multiple types of siloxane units with different properties. The composition includes a mixture of cyclic siloxane units (D3, D4, D5, D6) and linear siloxane units, forming a composite material that exhibits both low viscosity and high heat resistance. The synergistic effect of different siloxane units resolves the contradiction between fluidity and thermal stability.
2Reliability
If conventional curable organopolysiloxane compositions are used, then packaging material properties are achieved, but sticky surfaces and yellowing occur due to nonreactive residues
Solution Approach 1:
The patent eliminates the harmful nonreactive residues by carefully selecting and controlling the siloxane unit composition. By using specific cyclic siloxane units (D3, D4, D5, D6) in controlled ratios and ensuring complete reaction of all reactive groups, the patent removes the source of sticky surfaces and yellowing. The composition is designed to minimize or eliminate unreacted phenyl rings and other residue-forming groups.
Solution Approach 2:
The patent changes the chemical composition parameters by specifying precise molar ratios of different siloxane units and controlling the content of reactive groups. By adjusting these parameters, the patent ensures complete curing without leaving nonreactive residues that cause stickiness and yellowing, while maintaining the required packaging material properties.
3Ease of operation
If linear organopolysiloxane is used to reduce viscosity, then adhesive property improves, but mechanical strength decreases under high temperature
Solution Approach 1:
The patent creates a composite structure combining linear and cyclic siloxane units. The linear units provide good adhesive properties and low viscosity, while the cyclic units (D3, D4, D5, D6) contribute to mechanical strength and thermal stability. This composite approach allows the material to simultaneously exhibit good adhesion and high mechanical strength under elevated temperatures.
Solution Approach 2:
The patent introduces localized structural features by incorporating specific siloxane units with distinct functions at different positions within the polymer chain. The composition includes units optimized for adhesion at the interface and units optimized for mechanical strength in the bulk, creating local quality differentiation that resolves the contradiction between adhesive property and mechanical strength.
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 a cured product with low viscosity, high refractive index, excellent transmittance, and improved mechanical strength, preventing yellowing and stickiness, making it suitable for high-temperature applications and adaptable for various optical material demands.
Implementation Method 1
An organic silicon resin, such as organopolysiloxane, can be cured through alkylation with silicon hydrides
Implementation Method 2
an alkylation catalyst
Data Source
AI summary
A curable composition comprises the following: (A) a branched polymer having an average unit formula (I′):[(R″)2SiO2/2]a″[(CH2═CH)(R″)2SiO1/2]b″[R″SiO3/2]c″[O1/2Si(R″)2(CH2CH2)(R″)2SiO1/2]e″;(B) a branched organopolysiloxane having at least one silicon-bonded alkenyl group and having a siloxane unit of formula R4SiO3/2; (C) an organopolysiloxane having an average unit formula (II) being capped with H:(R52SiO2/2)f(R63SiO1/2)g(R7SiO3/2)h(SiO4/2)i(CH2CH2)j;and (D) a catalyst, wherein R″, R4 to R7, a″ to c″, e″ and f to j are as defined in the specification.