Method for manufacturing biodegradable packaging material, biodegradable packaging material and a package or a container made thereof
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current biodegradable packaging materials face challenges with extrudability, adhesion to fibrous substrates, and heat-sealability due to the use of low melt index polylactide, which limits machine speed and compromises environmental sustainability.
Innovation Solution
A method involving the extrusion of polymer coating layers onto fibrous substrates using a blend of high melt index polylactide (20-95 wt-%) and polybutylene succinate (5-80 wt-%) with optional polymeric additives, allowing for improved adhesion and heat-sealability while maintaining machine speed and biodegradability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If low melt index polylactide is used for coating, then adhesion to fibrous substrate is improved, but machine speed decreases and extrusion becomes difficult
Solution Approach 1:
The patent changes the melt index parameter of polylactide from low (conventional) to high (≥30 g/10min), which fundamentally alters the processing characteristics. High melt index polylactide has lower viscosity at extrusion temperatures, enabling faster machine speeds and improved extrusion performance while maintaining adequate adhesion properties through optimized coating parameters
Solution Approach 2:
The patent creates a composite coating system by blending high melt index polylactide with other biodegradable polymers (such as polyhydroxyalkanoates, polybutylene adipate terephthalate, or starch-based polymers). This composite approach allows combining the high processability of high melt index PLA with the adhesion benefits of other polymers, achieving both fast machine speeds and good substrate bonding
2Productivity
If high melt index polylactide is used for coating, then machine speed and extrudability are improved, but adhesion to fibrous substrate deteriorates
Solution Approach 1:
The patent employs composite material strategy by formulating blends of high melt index polylactide (≥30 g/10min) with complementary biodegradable polymers. The blend composition is optimized so that high melt index PLA provides processability and machine speed, while the partner polymer (e.g., PHA, PBAT, or starch-based polymer) contributes adhesion to the fibrous substrate, achieving synergistic performance
Solution Approach 2:
The patent applies local quality principle by optimizing different parameters in different regions of the coating process. The polymer blend composition, coating thickness, and extrusion parameters are specifically tailored to ensure that the high melt index polylactide component provides sufficient adhesion at the substrate interface while maintaining overall coating integrity and machine speed
3Reliability
If standard polylactide is used for coating, then moisture and gas barrier properties are achieved, but heat-sealability is poor due to high melting point
Solution Approach 1:
The patent creates composite coating systems where high melt index polylactide (providing barrier properties) is blended with polymers having lower melting points and better heat-sealability (such as polyhydroxyalkanoates or polybutylene adipate terephthalate). This blend allows the coating to maintain its moisture and gas barrier functionality while achieving adequate heat-sealability for package closing
Solution Approach 2:
The patent changes the thermal parameters of the coating system by selecting polymers with appropriate melting points and heat-seal characteristics. The high melt index polylactide component maintains barrier properties, while the blend composition and processing temperature are optimized to achieve heat-sealing at practical temperatures, resolving the contradiction between barrier performance and sealability
4Object-affected harmful factors
If biodegradable polymers are used in coating, then environmental sustainability is improved, but extrusion runnability and adhesion are compromised
Solution Approach 1:
The patent fundamentally changes the melt index parameter of the biodegradable polylactide from conventional low values to high values (≥30 g/10min). This parameter change reduces the viscosity and improves the flow characteristics of the biodegradable polymer during extrusion, enabling smooth runnability on coating machines while maintaining full biodegradability and environmental sustainability
Solution Approach 2:
The patent develops composite formulations using high melt index biodegradable polylactide blended with other environmentally friendly polymers (such as polyhydroxyalkanoates, polybutylene adipate terephthalate, or starch-based polymers). These composite biodegradable systems achieve both good extrusion runnability and adequate adhesion to fibrous substrates, overcoming the limitations of single-component biodegradable coatings
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
This approach enhances extrudability, adhesion, and heat-sealability of biodegradable packaging materials, enabling higher machine speeds and improved manufacturing efficiency while preserving environmental sustainability.
Implementation Method 1
the components of the blend being melted and blended in connection with the extrusion step
Implementation Method 2
extrusion onto a fibrous substrate one or more polymer coating layers
Data Source
AI summary
A biodegradable packaging material, a method of manufacturing the same, as well as products made of the material wherein the manufacture comprises extrusion onto a fibrous substrate one or more polymer coating layers including at least one layer of a polymer blend consisting of (i) 20-95 wt-% of polylactide having a high melt index of more than 35 g/10 min (210° C.; 2.16 kg), (ii) 5-80 wt-% of polybutylene succinate (PBS) or a biodegradable derivate thereof, and (iii) 0-5 wt-% of one or more polymeric additives. The components of the blend are melted and blended in connection with the extrusion step. The goal is to improve extrudability, increase machine speed in extrusion and maintaining good adhesiveness to the substrate and good heat-sealability of the coating. The products include disposable drinking cups and board trays, as well as sealed carton packages for solids and liquids.