Biorenewable Processing Aid for Oxygen Barrier Sealing Elements
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Thermoplastic elastomer sealing elements face challenges in achieving desirable oxygen barrier properties without contributing to the taste or odor of packaged products, while also being easily processable and resistant to high temperatures, as existing solutions like mineral oil and silicone oil either migrate or reduce barrier performance.
Innovation Solution
A sealing element composition comprising a styrenic block copolymer, a biorenewable processing aid with a crystalline melting range of 30-80°C, and an isobutylene-containing polymer or butyl rubber, which acts as both a processing aid and barrier synergist, enhancing oxygen barrier performance and processability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If mineral oil plasticizer is added to improve processability, then ease of manufacture is improved, but harmful factors (odor, taste, migration) are generated
Solution Approach 1:
The patent replaces conventional mineral oil plasticizers with biorenewable processing aids derived from natural sources (vegetable oils, animal fats). These biorenewable materials serve as temporary processing aids that can be easily removed or degraded, leaving no harmful residues in the final product. The processing aids improve manufacturability during extrusion and molding but do not contribute to odor or taste in the final sealing element.
Solution Approach 2:
The biorenewable processing aids act as intermediary substances that facilitate the processing of the sealing element composition without becoming permanent components of the final product. These intermediaries enable proper mixing and forming during manufacturing but are designed to be removable or non-migrating, thus preventing contamination of the packaged product with harmful substances.
2Ease of operation
If silicone oil is added to reduce removal torque, then ease of operation is improved, but barrier performance deteriorates
Solution Approach 1:
The patent modifies the chemical and physical parameters of the sealing element by incorporating specific biorenewable processing aids with controlled molecular weights, viscosity ranges, and polarity characteristics. These parameter adjustments allow the material to achieve appropriate removal torque without compromising oxygen barrier performance, as the biorenewable aids do not interfere with the barrier properties of the polymer matrix like silicone oil does.
3Reliability
If high molecular weight polyisobutylene is used to improve barrier properties, then oxygen barrier performance is improved, but viscosity increases making processing difficult
Solution Approach 1:
The biorenewable processing aids serve as intermediary substances that temporarily reduce the viscosity of high molecular weight polyisobutylene during processing. These processing aids interact with the polymer chains to decrease intermolecular friction, enabling easy extrusion and molding. After processing, the processing aids can be removed or become inactive, leaving the high molecular weight polyisobutylene to provide its full oxygen barrier performance without the viscosity penalty.
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 achieves significant reductions in oxygen permeability and viscosity, maintaining integrity and ease of processing, while being resistant to high temperatures and suitable for food contact applications.
Implementation Method 1
the biorenewable processing aid acts as a barrier synergist... Low oxygen permeability sealing elements can be formed from the compositions
Implementation Method 2
achieving desirable oxygen barrier properties without contributing to the taste or odor of packaged products, while also being easily processable
Implementation Method 3
maintaining integrity and ease of processing, while being resistant to high temperatures
Data Source
Figure 1~4
Figure 2~3
AI summary
Thermoplastic elastomer compositions, in particular derived from one or more styrenic block copolymers, a relatively high molecular weight isobutylene-containing (co)polymer, and a biorenewable processing aid. The isobutylene-containing (co)polymer imparts desirable oxygen barrier performance to the composition and the biorenewable processing aid acts as a barrier synergist as well as a processing aid useful during compounding. Low oxygen permeability sealing elements can be formed from the compositions. Processes for preparing the compositions and sealing elements are disclosed.