Sustainable Polyester Polyol Compositions from Recycled PET and Castor Oil

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The polyurethane foam industry relies heavily on petrochemical-based polyols, with limited use of biorenewable and recycled materials, particularly for flexible polyurethane foams, which lack sustainable and high-performance alternatives.

Innovation Solution

Development of a polyester polyol composition made from digested thermoplastic polyester, glycol, castor oil, and ricinoleic acid, with specific weight percentages and hydroxyl functionality ranges, utilizing recycled and biorenewable materials like recycled polyethylene terephthalate and castor oil, to produce flexible polyurethane foams with desirable properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If petrochemical-based polyether polyols are used to produce flexible polyurethane foams, then good load bearing properties and high reactivity are achieved, but sustainability and environmental friendliness deteriorate

Engineering Contradiction:
Improveperformance reliabilityVSAvoidenvironmental harm
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent changes the chemical composition parameters of the polyol by incorporating biorenewable resources (castor oil, ricinoleic acid) and recycled materials (recycled PET, PBT) into the polyester polyol structure. This transforms the polyol from petrochemical-based to sustainable-based while maintaining the required hydroxyl functionality (2.5-3.5) and hydroxyl number (20-150 mg KOH/g) for reliable foam performance.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite polyester polyol composition combining multiple components: digested thermoplastic polyester (5-30 wt%), glycol (2-20 wt%), and castor oil or ricinoleic acid (25-85 wt%). This composite structure integrates the benefits of different materials to achieve both sustainability and the required mechanical and chemical properties for flexible foam production.

Inventive Principle:
Principle #40Composite materials

2Object-affected harmful factors

If recycled thermoplastic polyester is used to make polyols, then sustainability improves, but the availability of suitable feedstock with required properties deteriorates

Engineering Contradiction:
Improveenvironmental harmVSAvoidfeedstock availability
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent modifies the properties of recycled thermoplastic polyester through controlled digestion to transform it into a suitable feedstock for polyol production. By adjusting the digestion conditions and subsequent reaction parameters, the process ensures that the recycled material achieves the required hydroxyl functionality and molecular weight distribution, making reliable feedstock availability possible.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent introduces an intermediary digestion process that breaks down the recycled thermoplastic polyester into suitable oligomeric fragments before incorporating it into the final polyol composition. This intermediary step ensures that the recycled material can be properly integrated while maintaining the required chemical and physical properties.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Ease of manufacture

If aromatic polyester polyols are used to produce flexible foams, then the production process is simplified, but compatibility with hydrocarbon blowing agents deteriorates

Engineering Contradiction:
Improveprocess simplicityVSAvoidcompatibility with blowing agents
Core Design Contradiction:
Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The patent adjusts the chemical parameters of the polyester polyol by incorporating castor oil or ricinoleic acid, which contain hydrophobic components that improve compatibility with hydrocarbon blowing agents. This parameter change in the polyol composition maintains process simplicity while enhancing the adaptability and compatibility with blowing agents.

Inventive Principle:
Principle #35Parameter changes

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 sustainable, high-performance polyester polyols with hydroxyl numbers and functionalities suitable for flexible polyurethane foams, reducing reliance on petrochemicals and enabling the production of foams with improved load-bearing, resilience, and viscoelastic properties.

Implementation Method 1

aromatic polyester polyols are made by polycondensation of diacids or anhydrides with diols

Methodology Applied
Scientific EffectPolycondensation: Chemical Bonding

Implementation Method 2

the polyols used to make these flexible foams are polyether-based materials

Methodology Applied
Scientific EffectViscoelasticity: Viscoelasticity

Data Source

PatentUS10155837B2Sustainable polyester polyol compositions
Publication Date: 2018.12.18 RESINATE MATERIALS GRP

AI summary

Polyester polyol compositions are disclosed. The polyol compositions, which comprise recurring units of a digested thermoplastic polyester, a glycol, and castor oil, ricinoleic acid, or a mixture of castor oil and ricinoleic acid, have hydroxyl numbers within the range of 20 to 150 mg KOH/g and average hydroxyl functionalities within the range of 2.5 to 3.5. The invention includes flexible polyurethane foams that incorporate the polyester polyols. Sustainable polyester polyols made completely or in substantial part from recycled, post-industrial, and/or biorenewable materials such as polyethylene terephthalate, glycols, and castor oil are provided. The polyols have desirable properties for formulating flexible polyurethane foams and other products.