Elevator Belt Bonding Layer for Adhesion and Fire Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Elevator systems face challenges with poor adhesion between polyurethane or elastomer sheaths and polymer matrix composite cores, and inadequate fire resistance in load-bearing belts, which are critical for safety and functionality.
Innovation Solution
A thermoplastic polyurethane or elastomer and phosphonate blended bonding agent is used as a tie-layer between the core and sheath in elevator belts, enhancing adhesion and incorporating phosphonate polymers for improved flame resistance, which can be extruded or co-extruded onto the core and sheath.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a polyurethane sheath is adhered to a polymer matrix composite core, then the belt structure is formed, but poor adhesion between the sheath and core occurs
Solution Approach 1:
A bonding agent comprising a blend of elastomer and phosphonate compounds is introduced as an intermediary layer between the polyurethane sheath and the polymer matrix composite core. This bonding agent contains specific functional groups that chemically interact with both the sheath and core materials, creating strong interfacial adhesion. The phosphonate compounds form chemical bonds with the core while the elastomer component bonds with the sheath, effectively mediating the interface between two incompatible materials.
Solution Approach 2:
The bonding agent itself is a composite material formed by blending elastomer with phosphonate compounds. This composite structure combines the adhesive properties of the elastomer with the chemical reactivity of phosphonates, creating a material that can simultaneously bond to both the polyurethane sheath and the composite core. The composite nature allows optimization of both adhesion and chemical bonding capabilities in a single layer.
2Object-affected harmful factors
If conventional materials are used for the core and sheath, then the belt can be manufactured, but fire resistance is inadequate
Solution Approach 1:
The bonding agent incorporates phosphonate compounds which fundamentally change the fire resistance parameter of the belt system. Phosphonates are known fire retardant compounds that interfere with combustion chemistry, forming protective char layers and releasing flame-inhibiting gases. This parameter change transforms the belt from flammable to fire-resistant without compromising the structural integrity of the core-sheath assembly.
Solution Approach 2:
The phosphonate compounds in the bonding agent convert the potential harm of combustion into benefit by acting as fire retardants. When exposed to fire, the phosphonates decompose endothermically, absorbing heat and forming protective carbonaceous layers that prevent further combustion. This transforms the bonding agent from a simple adhesive into an active fire protection system.
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 improves adhesion between the sheath and core, while also enhancing the fire resistance of the belts without using halogens, maintaining mechanical properties and allowing for the use of flame retardants in the polymer composite belt design.
Implementation Method 1
A TPU or other elastomer polymer or rubber and phosphonate blended bonding agent adheres the core to the sheath
Implementation Method 2
incorporating phosphonate polymers for improved flame resistance
Data Source
AI summary
A belt for an elevator system is provided having a core and an elastomeric sheath positioned over the core. An elastomer and phosphonate blended bonding agent adheres the core to the sheath.