Self-Adhesive Silicone Rubber Composition for Low-Temperature Resin Bonding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing addition curable silicone rubber compositions face challenges in achieving sufficient adhesion with general-purpose thermoplastic resins at low molding temperatures, leading to reduced curing speed and prolonged molding times, which compromises pot life and workability.
Innovation Solution
A self-adhesive silicone rubber composition is developed by blending an organopolysiloxane with alkenyl groups, an organosilicon compound containing a phenylene skeleton, organohydrogenpolysiloxane, a triazole compound, a platinum catalyst, reinforcement silica fine powder, and an acetylene alcohol compound or its modified form, allowing for rapid curing and sufficient pot life at low temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If addition curable silicone rubber composition is used for adhesion with general-purpose thermoplastic resins at low molding temperatures, then adhesion is improved, but curing speed is reduced and molding time is prolonged
Solution Approach 1:
The patent modifies the chemical composition parameters of the silicone rubber by incorporating specific adhesive components (organopolysiloxane with alkenyl groups, organosilicon compound with phenylene skeleton and Si-H bonds, organohydrogenpolysiloxane without phenylene skeleton) in controlled ratios. This compositional parameter change enables the material to achieve both strong adhesion to thermoplastic resins and maintained curing speed at low temperatures, resolving the contradiction between adhesion strength and productivity
Solution Approach 2:
The invention creates a composite adhesive system by combining multiple silicone rubber components with complementary functions: the organopolysiloxane provides base adhesion, the organosilicon compound with Si-H bonds enables crosslinking and strength, and the organohydrogenpolysiloxane enhances adhesion without phenylene interference. This composite approach allows simultaneous optimization of adhesion properties and curing characteristics, overcoming the trade-off between bond strength and curing efficiency
2Reliability
If molding temperature is reduced to prevent resin deformation, then resin integrity is maintained, but curing speed of silicone rubber is markedly reduced
Solution Approach 1:
The patent adjusts the chemical parameters of the silicone rubber composition by incorporating specific adhesive components that facilitate adhesion at lower temperatures without sacrificing curing kinetics. The organosilicon compound with phenylene skeleton and Si-H bonds, combined with organohydrogenpolysiloxane, creates a system that can cure effectively at reduced temperatures while maintaining resin integrity, thus resolving the contradiction between reliability and productivity
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 exhibits excellent adhesion to various organic resins, including polycarbonate, PBT, PET, polyamide, and polyphenylene sulfide, while maintaining rapid curing and extended pot life, suitable for producing integrally molded articles in automotive and electronic components.
Implementation Method 1
an addition curable silicone rubber composition comprising an organopolysiloxane (A) containing at least 2 alkenyl groups bonded to silicon atoms per molecule, an organosilicon compound (B) containing 1 to 100 silicon atoms per molecule, having at least 1 phenylene skeleton per molecule, and having at least 1 hydrogen atom bonded to silicon atom per molecule
Implementation Method 2
a platinum catalyst (E)
Implementation Method 3
This invention relates to an addition curable silicone rubber composition having self-adhesiveness which is capable of adhering to organic resins such as polyamide, polybuthylene terephthalate (PBT), polycarbonate, polyphenylene oxide, and polyphenylene sulfide
Data Source
AI summary
An addition curable self-adhesive silicone rubber composition is provided. This silicone rubber composition comprises (A) 100 parts by weight of an organopolysiloxane containing at least 2 alkenyl groups bonded to silicon atoms per molecule, (B) 0.05 to 10 parts by weight of an organosilicon compound containing 1 to 100 silicon atoms which has at least 1 phenylene skeleton per molecule, and which has at least 1 hydrogen atom bonded to a silicon atom, (C) 0 to 30 parts by weight of an organohydrogenpolysiloxane containing at least 2 hydrogen atoms bonded to silicon atoms per molecule, and containing no phenylene skeleton in the molecule, (D) 0.001 to 0.1 part by weight of a triazole compound, and (E) a catalytic amount of a platinum catalyst. This silicone rubber composition is capable of forming a cured article having good adhesion to various organic resins.