Multi-layer Silage Film with Density-Graded Ethylene Copolymers
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Polyethylene-based silage films incorporating polyisobutylene (PIB) face challenges such as process control difficulties due to PIB's liquid state at ambient temperatures, capital expenditures for liquid dosage systems, and migration issues at elevated temperatures, leading to film blocking and equipment jamming, necessitating a PIB-free or low-PIB film with maintained toughness and cling properties.
Innovation Solution
A multi-layer film with at least three layers, featuring two outer layers and a core layer, where the core layer comprises an ethylene copolymer with 1-octene and specific density ranges, and the outer layers include ethylene copolymers with densities between 0.850 and 0.890 g/cm³, enhancing cling properties and reducing component migration at elevated temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If polyisobutylene is added to improve cling properties, then cling properties are improved, but process control difficulties and capital expenditures for liquid dosage systems occur
Solution Approach 1:
The invention changes the physical state parameter of the adhesive component from liquid (PIB requiring dosage systems) to solid form (masterbatch), eliminating the need for complex liquid dosing equipment while maintaining cling properties
Solution Approach 2:
The invention uses a masterbatch as an intermediary carrier to deliver the PIB adhesive component in solid form, which then melts and distributes during the extrusion process, replacing the need for direct liquid dosing systems
2Strength
If polyisobutylene is used to enhance film properties, then toughness and cling are improved, but migration occurs at elevated temperatures causing film blocking
Solution Approach 1:
The invention places the PIB-containing adhesive layer specifically in the inner layer of the multi-layer structure, where it performs its cling function, while outer layers use migration-resistant polymers to prevent blocking at high temperatures
Solution Approach 2:
The invention creates a multi-layer composite film structure combining PIB-based adhesive layer for cling properties with migration-resistant polymer layers for thermal stability, achieving both toughness and resistance to film blocking
3Device complexity
If masterbatch comprising PIB is used instead of liquid dosing, then liquid dosage systems are eliminated, but a masterbatch compounding step must be included
Solution Approach 1:
The PIB adhesive component is pre-compounded into a masterbatch form before the film extrusion process, allowing it to be readily available in a stable, solid form that can be easily fed into the extruder without requiring liquid dosing equipment during production
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 multi-layer film achieves improved cling properties and reduced component migration during storage and use at high temperatures, while eliminating the need for precise liquid dosing and masterbatch compounding, thus addressing the drawbacks of PIB-containing films.
Implementation Method 1
the core layer comprises an ethylene copolymer comprising 1-octene and having a density between > 0.910 g/cm³ and 0.915 g/cm³
Implementation Method 2
such film demonstrates improved cling properties and further provides benefits in that a.o. migration of components from this film during storage and use at elevated temperatures is reduced
Data Source
AI summary
The present invention relates to a multi-layer film comprising at least three layers, with two outer layers, and one core layer, wherein: ⋅ the core layer comprises an ethylene copolymer comprising 1-octene and having a density between > 0.910 g/cm3 and 0.925 g/cm3, wherein further ⋅ the first outer layer comprises an ethylene homopolymer having a density of between > 0.915 g/cm3 and 0.930 g/cm3, wherein further ⋅ the second outer layer comprises and optional first ethylene copolymer and a second ethylene copolymer having a density of between 0.850 g/cm3 and < 0.890 g/cm3. Such film demonstrates improved cling properties and further provides benefits in that a.o. migration of components from this film during storage and use at elevated temperatures is reduced.