Rubber Cord Coating Composition for Aged Tire Adhesion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing rubber coating mixtures for metallic reinforcements, particularly those using resorcinol-based systems, face challenges in maintaining adhesion properties after aging, which affects the durability of reinforced rubber products.
Innovation Solution
A sulfur-curable rubber coating mixture comprising a novolak resin with alkyl urethane units, produced by reacting a phenol compound and a carbamate resin, combined with a sulfenimide accelerator, such as N-tert-butyl-2-benzothiazolesulfenimide, to enhance adhesion and reduce the need for hazardous sulfenamide accelerators.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If resorcinol-based adhesion systems are used in rubber coating mixtures, then initial adhesion to metallic reinforcements is achieved, but adhesion properties deteriorate after aging under oxygen exposure
Solution Approach 1:
The patent changes the chemical composition parameters of the adhesion system by replacing resorcinol-based systems with novolak resins containing alkyl urethane units. This parameter change maintains initial adhesion while improving resistance to oxygen aging, thereby resolving the contradiction between initial adhesion and aged adhesion properties.
Solution Approach 2:
The patent uses composite material approach by combining novolak resins with alkyl urethane units and sulfenimide accelerators in a specific formulation. This composite adhesion system provides both initial bonding capability and long-term stability under aging conditions, resolving the contradiction between initial adhesion and durability after aging.
2Productivity
If sulfenamide accelerators are used to achieve sufficient vulcanization, then crosslinking speed is improved, but health and environmental hazards increase
Solution Approach 1:
The patent replaces hazardous sulfenamide accelerators with sulfenimide accelerators that decompose more completely and produce fewer harmful byproducts. This substitution maintains vulcanization effectiveness while eliminating the health and environmental hazards associated with sulfenamide accelerators.
Solution Approach 2:
The patent converts the potential harm of accelerator residues into a benefit by selecting sulfenimide accelerators that decompose more completely during vulcanization, leaving minimal harmful residues. This transforms the accelerator selection from a source of contamination to a solution that reduces environmental and health hazards.
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 combination achieves improved adhesion to metallic reinforcements even after aging, enhancing the durability of rubber products by maintaining strong reinforcement-rubber bonds under oxygen exposure.
Implementation Method 1
sulfur-crosslinkable rubber coating mixture
Implementation Method 2
During the vulcanization process, a resin is formed from the methylene donor and the methylene acceptor
Implementation Method 3
which interacts adhesively with the surface of the reinforcement
Implementation Method 4
a second network based on methylene donor and methylene acceptor forms, which interacts adhesively with the surface of the reinforcement
Implementation Method 5
During the vulcanization process, a resin is formed from the methylene donor and the methylene acceptor
Implementation Method 6
a second network based on methylene donor and methylene acceptor forms
Data Source
AI summary
The invention relates to a sulfur-crosslinkable rubber-coating mixture for metal tyre cords, the mixture containing - 0.25 to 5 phr (parts by weight per 100 parts by weight of all the rubbers in the mixture) of at least one novolac resin that includes alkyl urethane units and is produced by reacting a phenol compound, an aldehyde and a carbamate resin, the carbamate resin being produced by reacting alkyl urethane with an aldehyde, and - 0.5 to 3 phr of at least one sulfenimide accelerator. The invention further relates to a pneumatic vehicle tyre that includes at least one sulfur-crosslinked rubber-coating mixture of this kind.