HDPE Cable Jacket Shrinkage Reduction via Elastomer Blending

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

High density polyethylene (HDPE) used in fiber optic cable jackets experiences excessive post-extrusion shrinkage, leading to signal attenuation due to its semi-crystalline nature, which existing optimizations have not adequately addressed, requiring further reduction in cyclic temperature shrinkage and excess fiber length.

Innovation Solution

A composition blending HDPE with a modifier component such as polyethylene glycol (PEG), polypropylene glycol (PPG), or diethylene glycol, along with optional carbon black and additives, to reduce cyclic temperature shrinkage and enhance processability of the extruded material.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If HDPE is used as cable jacketing material, then cost-effectiveness is improved, but post-extrusion shrinkage increases causing excess fiber length

Engineering Contradiction:
Improvecost-effectivenessVSAvoidpost-extrusion shrinkage
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent modifies the physical and chemical parameters of HDPE by blending it with elastomeric polymers (5-50 wt%) and using bimodal or multimodal molecular weight distributions. This changes the crystallization behavior and shrinkage characteristics of the material while maintaining its cost-effectiveness

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite material system by blending HDPE with elastomeric polymers such as EPR, EPDM, or POE. This composite approach combines the cost advantages of HDPE with the shrinkage resistance of elastomeric components, achieving both economic and performance goals

Inventive Principle:
Principle #40Composite materials

2Manufacturing precision

If HDPE chain architecture is optimized, then shrinkage reduction is improved, but development time and cost increase

Engineering Contradiction:
Improveshrinkage reductionVSAvoiddevelopment turnaround time
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

The patent performs preliminary action by pre-blending HDPE with elastomeric polymers in controlled ratios before extrusion. This pre-formulation approach allows shrinkage optimization to be achieved through simple mixing rather than complex reactor engineering, significantly reducing development time

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent changes the compositional parameters of the polymer blend rather than modifying the HDPE molecular structure itself. By adjusting the elastomer content (5-50 wt%) and type, shrinkage is controlled without requiring lengthy polymerization studies

Inventive Principle:
Principle #35Parameter changes

3Reliability

If cyclic temperature shrinkage is reduced, then signal attenuation is improved, but material composition complexity increases

Engineering Contradiction:
Improvesignal transmission qualityVSAvoidmaterial composition
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent uses composite materials by combining HDPE with well-established elastomeric polymers (EPR, EPDM, POE) that are already widely used in the industry. This approach reduces signal attenuation through reduced shrinkage while avoiding excessive complexity by using commercially available polymer blends

Inventive Principle:
Principle #40Composite materials

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 modified composition achieves a reduction in cyclic temperature shrinkage by 1-20% and lower viscosity, thereby minimizing signal attenuation and improving the extrusion process, while maintaining the cost-effectiveness of HDPE.

Implementation Method 1

HDPE is prone to excessive field shrinkage due to its semi-crystalline nature

Methodology Applied
Scientific EffectCrystallization: Crystallisation

Implementation Method 2

the composition has a viscosity of at least 1% to up to 15% lower than a composition having the same formulation but made without the modifier component

Methodology Applied
Scientific EffectViscosity reduction:

Data Source

PatentEP2935453B1Polyolefin-based compound for cable jacket with reduced shrinkage and enhanced processability
Publication Date: 2019.07.24 DOW GLOBAL TECHNOLOGIES LLC

AI summary

A composition comprising a blend of an ethylene-based thermoplastic polymer comprising high density polyethylene (HDPE) blended with a modifier component, and optionally with a carbon black and/or one or more additives to provide reduced shrinkage of the extruded composition and components made from the composition.