Axial Core Polymer Sheath Pellet for Stiffness Density Trade-off

Solution Overview

Problem

The reinforced plastics industry faces challenges in achieving sufficient stiffness in articles while maintaining a low density, as increasing glass fiber content in pellets makes them difficult to use in injection molding and results in higher density, which is undesirable, particularly in the automotive industry.

Innovation Solution

A pellet design featuring a glass filament core surrounded by a polymer sheath containing filler particles, such as glass bubbles or nanoclay, which reduces the overall density while maintaining or improving stiffness, achieved by optimizing the weight ratio of glass filaments to filler particles within the pellet.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If glass fiber content in pellets is increased to improve stiffness, then article stiffness is improved, but pellet density increases and injection molding becomes difficult

Engineering Contradiction:

Improvearticle stiffnessVSAvoidpellet density

Core Design Contradiction:

StrengthVSQuantity of substance

Solution Approach 1:

The patent applies composite materials by combining glass filaments with a polymer matrix in a controlled configuration. The core contains glass filaments surrounded by a polymer sheath, creating a composite structure that optimizes both stiffness and processability. This composite approach allows achieving high stiffness (4000-8000 MPa) while maintaining manageable density levels suitable for injection molding.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent implements local quality by creating a non-uniform distribution of glass filaments within the pellet. The core region has high glass filament concentration (30-70 wt%) for maximum stiffness, while the outer polymer sheath region has reduced glass content for better processability. This spatial variation in composition allows the pellet to exhibit both high stiffness and good injection molding characteristics.

Inventive Principle:

Principle #3Local quality

2Strength

If glass fiber content in pellets is increased to improve stiffness, then article stiffness is improved, but ease of operation in injection molding deteriorates

Engineering Contradiction:

Improvearticle stiffnessVSAvoidinjection molding processability

Core Design Contradiction:

StrengthVSEase of operation

Solution Approach 1:

The patent implements local quality by creating a non-uniform distribution of glass filaments within the pellet. The core region has high glass filament concentration (30-70 wt%) for maximum stiffness, while the outer polymer sheath region has reduced glass content for better processability. This spatial variation in composition allows the pellet to exhibit both high stiffness and good injection molding characteristics.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent applies composite materials by combining glass filaments with a polymer matrix in a controlled configuration. The core contains glass filaments surrounded by a polymer sheath, creating a composite structure that optimizes both stiffness and processability. This composite approach allows achieving high stiffness (4000-8000 MPa) while maintaining manageable density levels suitable for injection molding.

Inventive Principle:

Principle #40Composite materials

3Strength

If glass fiber content in pellets is increased to improve stiffness, then article stiffness is improved, but article weight increases

Engineering Contradiction:

Improvearticle stiffnessVSAvoidarticle weight

Core Design Contradiction:

StrengthVSWeight of stationary object

Solution Approach 1:

The patent implements local quality by creating a non-uniform distribution of glass filaments within the pellet. The core region has high glass filament concentration (30-70 wt%) for maximum stiffness, while the outer polymer sheath region has reduced glass content for better processability. This spatial variation in composition allows the pellet to exhibit both high stiffness and good injection molding characteristics.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent applies composite materials by combining glass filaments with a polymer matrix in a controlled configuration. The core contains glass filaments surrounded by a polymer sheath, creating a composite structure that optimizes both stiffness and processability. This composite approach allows achieving high stiffness (4000-8000 MPa) while maintaining manageable density levels suitable for injection molding.

Inventive Principle:

Principle #40Composite materials

Data Source

PatentUS12083710B2Pellet comprising an axial core and a polymer sheath, and its manufacture

Publication Date: 2024.09.10 SABIC GLOBAL TECHNOLOGIES BV

AI summary

Pellet having an axial direction and comprising a core that extends in the axial direction and further comprising a polymer sheath applied around said core, wherein said core comprises a plurality of filaments that extend in the axial direction; said polymer sheath is at least substantially free of said filaments; said polymer sheath comprising a plurality of filler particles; said pellet comprises at least 30%, preferably at least 35%, more preferably at least 40%, and preferably at most 60%, preferably at most 50%, of filaments by weight of the total weight of said pellet. Further disclosed is a reinforced article obtained from molding a plurality of said pellets, and a method of making such a pellet.