Single-Layer Fuel-Barrier Layer for Flexible Tubing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing multilayer structures for fuel tubes require multiple extruders to achieve both flexibility and fuel permeation resistance, making them inefficient in terms of productivity.
Innovation Solution
A single-layer fuel-barrier layer composed of a polyamide resin with a hydrocarbon chain of 10 or more carbon atoms as a continuous phase and a semi-aromatic polyamide resin as a disperse phase, with a mean disperse particle diameter of 150 nm or more, processed using a single-screw extruder to enhance flexibility and fuel permeation resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a multilayer structure with a barrier layer is used to improve fuel permeation resistance, then barrier performance is improved, but device complexity and productivity deteriorate due to requiring multiple extruders
Solution Approach 1:
The patent combines the flexible polyamide resin (A) and semi-aromatic polyamide resin (B) into a single-layer fuel-barrier layer, merging the functions of flexibility and barrier performance into one homogeneous layer. This eliminates the need for multiple extruders while maintaining both flexibility and fuel permeation resistance.
Solution Approach 2:
The patent creates a composite material system by blending polyamide resin (A) with semi-aromatic polyamide resin (B) in specific ratios (5-50 mass%). This composite approach allows the single layer to exhibit both the flexibility of polyamide (A) and the superior barrier properties of semi-aromatic polyamide (B).
2Reliability
If a multilayer structure with a barrier layer is used to improve fuel permeation resistance, then barrier performance is improved, but productivity deteriorates due to complex manufacturing process
Solution Approach 1:
The patent merges the barrier layer function into the single fuel-barrier layer by incorporating semi-aromatic polyamide resin (B) at 5-50 mass% of polyamide resin (A). This allows one extruder to produce a layer that simultaneously provides flexibility and superior barrier performance against alcohol gasoline, eliminating the need for separate barrier layers.
3Ease of operation
If polyamide resin alone is used to ensure flexibility, then flexibility is maintained, but fuel permeation resistance deteriorates
Solution Approach 1:
The patent creates a composite material by blending flexible polyamide resin (A) with semi-aromatic polyamide resin (B) having superior barrier properties. The specific composition ratio (5-50 mass% of resin B) ensures that the composite maintains the flexibility of polyamide (A) while gaining the enhanced fuel permeation resistance of semi-aromatic polyamide (B).
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 provides a tubular structure with excellent flexibility and fuel permeation resistance while simplifying the production process, reducing the need for multiple extruders and improving productivity.
Implementation Method 1
the fuel-barrier layer needs to be formed of two or more layers in order to satisfy both fuel permeation resistance (barrier performance) and flexibility
Implementation Method 2
processed using a single-screw extruder to enhance flexibility and fuel permeation resistance
Data Source
Figure 1~2
AI summary
A molded article comprising a fuel-barrier layer formed of a resin composition comprising a polyamide resin (A) as a continuous phase and a resin (B) as a disperse phase, wherein (A) is a polyamide resin (A1) comprising at least one of a constituent unit derived from a lactam having 10 to 12 carbon atoms and a constituent unit derived from an aminocarboxylic acid having 10 to 12 carbon atoms, or a polyamide resin (A2) comprising a constituent unit derived from an aliphatic diamine having 6 to 12 carbon atoms and a constituent unit derived from an aliphatic dicarboxylic acid having 10 to 12 carbon atoms, the (B) is a resin selected from a semi-aromatic polyamide resin, the ratio by volume of (A)/(B) is 95/5 to 51/49, and the mean disperse particle diameter of (B) is 150 nm or more.