Benzotriazole Additive Lowers Compression Set in Silicone Rubber
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Silicone rubbers used in applications like O-rings and gaskets face challenges with high compression set and decelerated cure rate when triazole compounds are added to reduce compression set, compromising mechanical properties and cure efficiency.
Innovation Solution
Incorporating a specific benzotriazole derivative into an addition-curable silicone rubber composition comprising organopolysiloxane, organohydrogenpolysiloxane, and a platinum catalyst, which maintains the cure rate while reducing compression set without secondary vulcanization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a triazole compound is added to an addition-curable silicone rubber composition to reduce compression set, then compression set is reduced, but cure rate is decelerated
Solution Approach 1:
The patent changes the chemical structure parameters of the triazole compound by introducing specific substituents (alkyl groups with 1-10 carbon atoms, aryl groups, or aralkyl groups) at the 1-position of the triazole ring. This structural modification allows the compound to reduce compression set while maintaining cure rate, resolving the technical contradiction between these two properties.
Solution Approach 2:
The patent creates a composite additive system by combining specifically modified triazole derivatives with platinum catalysts in controlled ratios (0.01-10 parts by weight of triazole derivative per 100 parts by weight of polysiloxane, and 0.001-0.1 parts by weight of platinum catalyst per 100 parts by weight of polysiloxane). This composite approach enables simultaneous achievement of low compression set and maintained cure rate.
2Reliability
If secondary vulcanization is performed at high temperature for a long time to reduce compression set, then compression set is reduced, but manufacturing time and energy consumption increase
Solution Approach 1:
The patent incorporates specially designed triazole derivatives into the silicone rubber composition before curing. These pre-added compounds act as compression set reducers during the initial curing process itself, eliminating the need for subsequent secondary vulcanization treatments. This preliminary action achieves low compression set while significantly reducing total manufacturing time.
Solution Approach 2:
The patent extracts and eliminates the secondary vulcanization step from the manufacturing process by incorporating compression set reduction functionality directly into the curing composition through the triazole derivative additive. This removes the separate high-temperature long-duration treatment step, reducing both time and energy requirements.
3Productivity
If conventional silicone rubber is used without compression set reduction additives, then cure rate is maintained, but compression set remains substantial and seal reliability is compromised
Solution Approach 1:
The patent introduces triazole derivatives as intermediary compounds that mediate between the crosslinking reaction and the final network structure. These intermediaries modify the curing process to create a more stable rubber network with lower compression set, while the platinum catalyst continues to maintain efficient cure rates. The triazole derivative acts as a mediator that improves reliability without sacrificing 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 solution achieves a silicone rubber with low compression set and minimal heat discoloration, maintaining mechanical properties and cure efficiency, suitable for high-temperature applications.
Implementation Method 1
an addition-curable silicone rubber composition comprising: (A) 100 parts by weight of an alkenyl-containing organopolysiloxane having at least two silicon-bonded alkenyl groups per molecule, (B) an organohydrogenpolysiloxane having at least two silicon-bonded hydrogen atoms per molecule, in an amount of 0.2 to 20 parts by weight per 100 parts by weight of component (A), (C) a catalytic amount of a platinum catalyst
Implementation Method 2
when a specific amount of a benzotriazole derivative of specific structure represented by the general formula (I) to be described below is added to an addition-curable silicone rubber composition comprising an organopolysiloxane containing silicon-bonded alkenyl, an organohydrogenpolysiloxane, and a platinum catalyst, there is obtained an addition-curable silicone rubber composition which cures into a silicone rubber or cured product having a low compression set without compromising the cure rate
Data Source
AI summary
Provided is an addition-curable silicone rubber composition containing(A) an alkenyl group-containing organopolysiloxane having alkenyl groups bonded to at least two silicon atoms per molecule,(B) an organohydrogenpolysiloxane containing hydrogen atoms bonded to at least two silicon atoms per molecule,(C) a platinum catalyst, and(D) a benzotriazole derivative represented by general formula (I)(in the formula, R1 is a hydrogen atom or monovalent hydrocarbon group, R2 is a monovalent organic group)that makes it possible to provide silicone rubber that can lower the compression set without harming the curing rate and suppress discoloration after a heat resistance test.