Foamed Polyolefin Cable Layer for Flexibility Without Tensile Loss
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cable jacketing materials, such as LDPE, LLDPE, and HDPE, fail to balance flexibility and tensile properties, leading to installation difficulties and potential damage during installation due to insufficient toughness and stress cracking resistance, while foaming these materials further compromises tensile properties.
Innovation Solution
A foamable polymer composition using citric acid and/or its derivatives or expandable polymeric microspheres as blowing agents, combined with linear low density polyethylene, to achieve controlled foaming and maintain mechanical integrity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional polyolefin materials (LDPE, LLDPE, HDPE) are used for cable jacketing, then material availability and ease of manufacture are improved, but flexibility and toughness are insufficient leading to installation difficulties
Solution Approach 1:
The patent changes the physical-chemical parameters of the polyolefin material by introducing a foamed structure with controlled cell size and distribution. This transforms the dense solid structure into a cellular structure, fundamentally altering mechanical properties like flexibility and toughness while maintaining the base polymer's ease of manufacture
Solution Approach 2:
The patent creates a composite structure by combining polyolefin polymer with blowing agents and foaming agents to produce a foamed composite material. This composite structure integrates the polymer matrix with gas-filled cells, achieving superior flexibility and installation characteristics compared to solid polyolefin
2Ease of operation
If polyolefin materials are foamed to improve flexibility, then flexibility and ease of installation are improved, but tensile properties and stress cracking resistance deteriorate
Solution Approach 1:
The patent applies local quality control by creating a specific foamed structure where cell walls and cell structures are optimized to provide flexibility in certain directions while maintaining tensile strength in critical loading directions. The non-uniform cell distribution and varied cell sizes create localized properties that balance flexibility and strength
Solution Approach 2:
The patent utilizes porous material science by controlling the pore structure, pore size distribution, and porosity of the foamed polyolefin. The specific porous structure provides flexibility through cell collapse mechanisms while maintaining tensile integrity through interconnected cell walls and optimized pore geometry
3Ease of operation
If foaming agents are added to polyolefin composition, then flexibility is improved, but material complexity and manufacturing precision requirements increase
Solution Approach 1:
The patent introduces intermediary substances (blowing agents and foaming agents) that mediate between the polyolefin base material and the desired foamed structure. These intermediaries facilitate controlled cell formation during extrusion, managing the complexity of creating uniform foam structures while maintaining manufacturing feasibility
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 composition provides cables with enhanced flexibility, improved resistance to breakage during installation, and reduced material costs, while meeting mechanical and electrical property standards, including stress at break and expansion degree.
Implementation Method 1
a blowing agent in an amount of 0.01 to 3 wt. % based on the total foamable polymer composition, wherein the blowing agent consists of citric acid and/or derivatives of citric acid
Implementation Method 2
Expandable polymeric microspheres as blowing agents, in a foamable polymer composition... to achieve controlled foaming
Data Source
AI summary
The invention relates to a foamable polymer composition comprising a polyolefin polymer which polyolefin polymer does not bear silane moieties and comprises 20 to 99.99 wt. % linear low density polyethylene, and a blowing agent in an amount of 0.01 to 3 wt. % based on the total foamable polymer composition, wherein the blowing agent consists of citric acid and/or derivatives of citric acid or mixtures thereof. Further the invention relates to a foamable polymer composition comprising a polyolefin polymer, and a blowing agent in an amount of 0.01 to 3 wt. % based on the total foamable polymer composition, wherein the blowing agent consists of expandable polymeric microspheres, and the composition does not comprise fluororesin.Further the invention relates to a foamed polymer composition obtained by foaming this foamable polymer composition. Further the invention relates to the use of the foamable composition or the foamed polymer composition for a layer of a cable and a cable comprising at least one layer which comprises the foamable polymer composition or the foamed polymer composition.