Polyolefin Polyamide Fuel Barrier Structure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current resin fuel containers, particularly those made of polyethylene, lack adequate fuel barrier properties and heat resistance, failing to meet stringent regulations for fuel permeation and impact resistance, especially when used for alcohol-containing fuels.
Innovation Solution
A single-layered structure composed of 50-97% polyolefin, 2-45% polyamide resin with a specific constitutional monomer ratio, and 1-45% modified polyolefin and/or styrene copolymer, where the polyamide resin is dispersed in layers, enhancing fuel barrier and heat resistance properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If polyethylene is used for resin fuel containers, then mechanical strength and moldability are excellent, but fuel barrier properties are poor
Solution Approach 1:
The invention uses a composite resin composition combining polyethylene (50-97 wt%), polyamide resin (2-45 wt%), and modified polyolefin/styrene copolymer (1-45 wt%). This composite structure leverages the mechanical strength of polyethylene while incorporating polyamide's superior fuel barrier properties, resolving the contradiction between strength and barrier performance
Solution Approach 2:
The invention changes the compositional parameters by specifying precise weight percentage ranges for each component and the molar ratio of constitutional units in polyamide resin (3:7 to 10:0). These parameter optimizations ensure the composite achieves both adequate mechanical strength and excellent fuel barrier properties meeting regulatory requirements
2Reliability
If barrier resin is blended into polyolefin, then fuel permeation is reduced, but absorption ability of crash impact is reduced and moldability becomes poor
Solution Approach 1:
The invention optimizes the weight percentage of polyamide resin to 2-45%, preventing excessive barrier resin addition that would harm impact absorption. This parameter control maintains the balance between fuel barrier properties and mechanical toughness
Solution Approach 2:
The invention specifies that polyamide resin should be dispersed in layers throughout the single-layered structure. This controlled dispersion creates local barrier regions that provide fuel permeation resistance while maintaining the overall matrix's impact absorption capability
3Reliability
If known barrier resins such as nylon 6 and ethylene-vinyl alcohol copolymers are used, then fuel barrier properties are provided, but barrier properties against alcohols are poor
Solution Approach 1:
The invention specifies precise compositional parameters for polyamide resin including the molar ratio of constitutional units (3:7 to 10:0) and weight percentage (2-45%). These optimized parameters enhance the resin's resistance to alcohol-containing fuels while maintaining general fuel barrier properties
Solution Approach 2:
The composite structure combines polyamide resin with polyethylene and modified polyolefin/styrene copolymer, creating a material system that provides broad-spectrum fuel barrier properties including resistance to alcohol-containing fuels, exceeding the performance of known barrier resins
4Reliability
If addition amount of barrier resin is increased, then fuel permeation is reduced, but moldability becomes poor
Solution Approach 1:
The invention sets the polyamide resin content within 2-45 wt% and specifies the molar ratio of constitutional units (3:7 to 10:0). These optimized parameters ensure sufficient fuel barrier properties while maintaining moldability for blow molding and other forming processes
Data Source
AI summary
The single-layered structure of the invention comprises (A) 50 to 97% by weight of a polyolefin, (B) 2 to 45% by weight of a polyamide resin comprising a diamine component and a dicarboxylic acid component and (C) 1 to 45% by weight of a modified polyolefin and/or styrene copolymer. The polyamide resin B is dispersed in layers throughout the single-layered structure. With such a dispersion state of the polyamide resin B, the single-layered structure exhibits excellent fuel barrier properties.