Biodegradable Film Laminated to Fibrous Substrate
Solution Overview
Problem
Current biodegradable and paper recyclable food containers face challenges in being liquid impermeable and safe for food handling applications, as they often require fossil-based polymers that are not environmentally friendly and can degrade at high temperatures, preventing them from being recycled or composted.
Innovation Solution
A laminated article is created using a shaped fibrous substrate from plant fibers with a biodegradable film, such as a cellulose ester polymer, that is thermoformed and bonded with a biodegradable adhesive to provide a liquid impermeable barrier, capable of withstanding freezing and heating without delamination or degradation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If fossil-based polymers (polyethylene, polyfluoroalkyl) are used to make containers liquid impermeable, then liquid resistance is improved, but environmental compatibility deteriorates (not biodegradable, not recyclable, incinerated or landfilled)
Solution Approach 1:
The patent changes the chemical composition parameters of the barrier film from fossil-based polymers to bio-based polymers (polysaccharide esters, cellulose esters, starch derivatives) while maintaining the liquid barrier function. This parameter change enables both liquid impermeability and environmental compatibility through biodegradability and compostability
Solution Approach 2:
The patent creates a composite structure combining fibrous substrate (paper, cardboard, biodegradable plastic) with a biodegradable polymer film barrier layer. This composite material approach integrates the liquid barrier properties of the film with the structural integrity of the substrate, while both components are environmentally compatible
2Object-affected harmful factors
If bio-based polymers are used to replace fossil-based polymers, then environmental compatibility is improved, but mechanical properties and heat resistance deteriorate (bubble, warp, or become damaged at higher temperatures)
Solution Approach 1:
The patent modifies the physical and chemical parameters of bio-based polymers through plasticization (adding plasticizers to reduce crystallinity and increase flexibility), blending with other biodegradable polymers, and optimizing molecular weight and composition to achieve sufficient mechanical strength and heat resistance for food container applications
Solution Approach 2:
The patent introduces plasticizers as intermediary substances that modify the properties of bio-based polymers, reducing brittleness and improving flexibility and heat resistance. The plasticizers act as mediators between the rigid polymer chains, enabling the material to withstand processing and use temperatures without warping or deforming
3Duration of action of stationary object
If bio-based polymers are used to replace fossil-based polymers, then biodegradability is improved, but temperature stability deteriorates (sensitive to higher temperatures)
Solution Approach 1:
The patent adjusts the thermal stability parameters of bio-based polymers by selecting polymers with appropriate glass transition temperatures, adding heat-stabilizing additives, and optimizing the polymer composition to withstand processing temperatures (extrusion, molding) and use conditions (microwave heating, hot filling) while maintaining biodegradability
Solution Approach 2:
The patent employs heat-stabilizing additives and plasticizers as intermediary substances that protect the bio-based polymer from thermal degradation. These intermediaries absorb or dissipate thermal energy, preventing chain scission and cross-linking that would otherwise occur at elevated temperatures, thereby maintaining both temperature stability and biodegradability
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 results in a biodegradable and recyclable food container that is safe for food contact, resistant to liquids, and can be used for both frozen and heated applications without compromising its structure, allowing for composting or recycling, thus addressing the environmental concerns of traditional plastic containers.
Implementation Method 1
Heat is generated by the heating element such that the heat from the heating element increases the temperature of the film. The heat from the heating element increases the temperature of the film to a forming temperature range where the film has been softened.
Implementation Method 2
While the film is within the forming temperature range, a suction force is applied to the film through the substrate and the substrate holder. The suction force manipulates the film such that the film contacts at least a portion of the substrate surface.
Implementation Method 3
An adhesive composition is optionally positioned between the surface of the fibrous substrate and the film. The adhesive composition bonds the film to the fibrous substrate.
Data Source
AI summary
The present disclosure is directed to laminated articles, such as articles for food and beverages, that are biodegradable and/or paper recyclable. The articles include a substrate comprising a film layer. The film layer is formed from a film made from biodegradable and/or paper recyclable polymer materials. The film layer is resistant and/or impermeable to liquids The article is capable of being frozen and/or heated using, for instance, a microwave oven without delaminating.