PTT Copolymer from PET Depolymerization

Solution Overview

Problem

Conventional processes for preparing polytrimethylene terephthalate (PTT) are energy-intensive and do not effectively reduce the amount of polyethylene terephthalate (PET) scrap that is incinerated or landfilled, necessitating the development of novel processes to produce PTT from non-monomeric sources and modified PTT random copolymers with comparable performance properties to monomer-derived PTT.

Innovation Solution

A process involving the depolymerization of PET or PET copolymers with 1,3-propanediol under atmospheric pressure and subsequent temperature increase to form a polytrimethylene terephthalate random copolymer, which contains residues from the PET component, allowing for the creation of PTT from recycled PET rather than monomers, thereby reducing waste and energy consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If PTT is prepared from monomers using conventional processes, then the polymer can be produced with desired performance properties, but the process requires substantial energy and does not reduce PET waste

Engineering Contradiction:

Improveperformance propertiesVSAvoidenergy consumption

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The invention changes the fundamental parameter of raw material source from monomers to PET scrap, transforming the chemical starting point while maintaining the desired polymer performance through controlled depolymerization and repolymerization processes

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention recovers value from discarded PET scrap materials by depolymerizing them into monomers and repolymerizing into PTT, thereby reducing waste while producing useful polymer material with desired properties

Inventive Principle:

Principle #34Discarding and recovering

2Reliability

If PTT is prepared from monomers using conventional processes, then the polymer can be produced with desired performance properties, but the process requires substantial energy

Engineering Contradiction:

Improveperformance propertiesVSAvoidenergy consumption

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The invention changes the fundamental parameter of raw material source from monomers to PET scrap, transforming the chemical starting point while maintaining the desired polymer performance through controlled depolymerization and repolymerization processes

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The invention converts the harmful waste disposal problem into a beneficial resource by using PET scrap as feedstock, thereby eliminating waste while producing valuable polymer material with reduced energy requirements

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Loss of substance

If PET scrap is disposed into landfills or incinerated, then waste management is achieved, but significant waste is created and non-renewable resources are destroyed

Engineering Contradiction:

Improvewaste reductionVSAvoidenvironmental harm

Core Design Contradiction:

Loss of substanceVSObject-generated harmful factors

Solution Approach 1:

The invention recovers value from discarded PET scrap materials by depolymerizing them into monomers and repolymerizing into PTT, thereby reducing waste while producing useful polymer material with desired properties

Inventive Principle:

Principle #34Discarding and recovering

Solution Approach 2:

The invention converts the harmful waste disposal problem into a beneficial resource by using PET scrap as feedstock, thereby eliminating waste while producing valuable polymer material with reduced energy requirements

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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 process effectively converts recycled PET into a PTT random copolymer with similar performance properties to monomer-based PTT, reducing waste disposal and energy usage, and can incorporate biomass-derived 1,3-propanediol to further minimize environmental impact.

Implementation Method 1

depolymerizing a polyethylene terephthalate component by reacting the polyethylene terephthalate component with 1,3-propanediol under conditions sufficient to depolymerize the polyethylene terephthalate component into a molten mixture containing polyethylene terephthalate oligomers, polytrimethylene terephthalate oligomers, mixed diol oligomers, 1,3-propanediol, and ethylene glycol

Methodology Applied

Scientific EffectDepolymerization: Decomposition (biological)

Implementation Method 2

The polymerization conditions are selected so as to produce molten polyester having a target intrinsic viscosity of at least about 0.4 dl/g, preferably about 0.4 to about 1.0 dl/g

Methodology Applied

Scientific EffectPolycondensation: Chemical Bonding

Data Source

PatentUS7902264B2Polytrimethylene terephthalate (PTT) derived from polyethylene terephthalate (PET) and containing PET residues

Publication Date: 2011.03.08 SHPP GLOBAL TECH BV

AI summary

A composition comprising a polytrimethylene terephthalate random copolymer that (1) is derived from polyethylene terephthalate component selected from the group consisting of polyethylene terephthalate and polyethylene terephthalate copolymers and (2) contains at least one residue derived from the polyethylene terephthalate component. Methods for making such copolymers and articles made from such copolymers.